Individuals at extremely high risk of developing psychosis appear less likely to develop psychotic disorders following a 12-week course of fish oil capsules containing long-chain omega-3 polyunsaturated fatty acids, according to a report in the February issue of Archives of General Psychiatry, one of the JAMA/Archives journals.
"Early treatment in schizophrenia and other psychoses has been linked to better outcomes," the authors write as background information in the article. "Given that subclinical psychotic symptoms may predict psychotic disorder and psychosis proneness in a population may be related to the rate of psychotic disorder, intervention in at-risk individuals holds the promise of even better outcomes, with the potential to prevent full-blown psychotic disorders."
Long-chain omega-3 polyunsaturated fatty acids are a promising intervention in individuals with schizophrenia, who may have an underlying dysfunction in fatty acid metabolism, the authors note. G. Paul Amminger, M.D., of Medical University of Vienna, Austria, and Orygen Youth Health Research Centre, Melbourne, Australia, conducted a randomized, double-blind, placebo-controlled clinical trial of their effect on the risk of progression to psychosis in 81 individuals at ultra–high risk. These individuals either had mild psychotic symptoms, transient psychosis or a family history of psychotic disorders plus a decrease in functioning. These criteria identify individuals whose risk of becoming psychotic may be as high as 40 percent in a 12-month period.
For 12 weeks, 41 individuals were assigned to take daily fish oil capsules containing 1.2 grams of omega-three polyunsaturated fatty acids and 40 were assigned to take placebo; a total of 76 (93.8 percent) completed the intervention. By the end of the study, two (4.9 percent) in the omega-3 group and 11 (27.5 percent) in the placebo group had transitioned to psychotic disorder. The difference between progression to psychosis was 22.6 percent.
Based on the results, the authors estimate that four adults would need to be treated with omega-3 fatty acids to prevent one from developing psychosis over a 12-month period. Polyunsaturated fatty acids also significantly reduced symptoms and improved functioning compared with placebo. Rates of adverse effects were minimal and similar between the two groups.
The potential effects of fatty acids on psychosis development may result from changes to cell membranes and interactions with neurotransmitter systems in the brain, the authors note. "The finding that treatment with a natural substance may prevent or at least delay the onset of psychotic disorder gives hope that there may be alternatives to antipsychotics for the prodromal [early symptomatic] phase," the authors write. "Stigmatization and adverse effects—which include metabolic changes, sexual dysfunction and weight gain—associated with the use of antipsychotics are often not acceptable for young people."
In contrast, omega-3 fatty acids may cause some digestive complications but largely "are free of clinically relevant adverse effects. They have the advantage of excellent tolerability, public acceptance, relatively low costs and benefits for general health," the authors conclude. "Long-chain omega-3 fatty polyunsaturated fatty acids reduce the risk of progression to psychotic disorder and may offer a safe and efficacious strategy for indicated prevention in young people with subthreshold psychotic states."
Tuesday, February 2, 2010
Play Soccer for Your Health
A just published research experiment on inactive men with high blood pressure shows that just 3 months of soccer practise twice a week causes a significant fall in blood pressure, resting pulse rate, and percentage of body fat, and is more effective than the doctor's usual advice on healthy diet and exercise. Other parallel experiments on both women and men further demonstrates that a regular game of soccer affects numerous cardiovascular risk factors such as maximal oxygen uptake, heart function, elasticity of the vascular system, blood pressure, cholesterol and fat mass far more than e.g. strength training and just as much if not more than running.
Each of the experiments was controlled randomized studies where the soccer groups were compared to other exercise groups and inactive controls. The soccer experiments are part of a large-scale research project on soccer and health carried out at the University of Copenhagen, four Danish University Hospitals, the Swiss Federal Institute of Technology and the Schulthess Clinic in Zurich.
Project Leader and Associate Professor at the University of Copenhagen Peter Krustrup recaps the results: "Our research shows that soccer is a versatile and intense form of exercise that provides a positive effect on cardiovascular risk factors in a large group of untrained adult men and women," and continues: "Based on the results, soccer can be recommended as part of the treatment for high blood pressure and as broad-spectred prevention of cardiovascular diseases."
Small games, big gains
When untrained children, teens, adults and older people play soccer, their pulse rate remains high and they perform multiple intense actions like sprints, turns, kicks and tackles.
"Our analyses also showed that the pulse rate and activity profile is the same in small-sided games where only 4, 6, 8 or 14 people play. In other words, it is very easy to obtain a combination of cardio and strength training with soccer," concludes Krustrup
Research partner Lars Juel Andersen from the Clinic of Sport Cardiology at Gentofte Hospital, Denmark, believes that the results are good news for the millions of people worldwide, suffering from high blood pressure: "It is well known that physical inactivity is a substantial risk factor in developing cardiovascular diseases in itself, but it is new that a pleasurable team sport like soccer is effective in treating high blood pressure". Furthermore, associate professor Peter Riis Hansen from Gentofte Hospital suggests that football may have other favourable effects on the vascular system, namely a reduction of arterial stiffness, which has been associated with improved cardiovascular outcomes.
About the project
Led by Professors Peter Krustrup and Jens Bangsbo from Department of Exercise and Sports Sciences, University of Copenhagen, 50 researchers from seven countries have studied the physical, psychological and social aspects of soccer and the results are remarkable. A number of scientific articles from the project are published on 2 February 2010 at a seminar at the University of Copenhagen and later this month the Scandinavian Journal of Medicine and Science in Sports will publish a special edition issue entitled "Football for Health" containing 14 scientific articles from the soccer project. The research project has received funding from FIFA - Medical Assessment and Research Centre (F-MARC), The Danish Ministry of Culture, TrygFonden, United Federation of Danish Workers (3F), The Danish Football Association, Team Denmark and The Danish Sports Confederation.
Further research plans:
The researchers have specific plans to examine the effect of soccer on other patient groups such as people with diabetes II and cancer. The research group is also planning a follow-up study of the long-term effects of soccer on high blood pressure and preliminary stages of osteoporosis. A planned collaboration with an international network of researchers from, among others, England, Italy, Portugal, Switzerland, Germany, Norway, Sweden, USA, Kenya and Iran will examine the cardiovascular and muscular-skeletal effects of soccer and other ball games such as basketball, handball, volleyball and floorball on inactive and overweight children and inactive elderly people.
Each of the experiments was controlled randomized studies where the soccer groups were compared to other exercise groups and inactive controls. The soccer experiments are part of a large-scale research project on soccer and health carried out at the University of Copenhagen, four Danish University Hospitals, the Swiss Federal Institute of Technology and the Schulthess Clinic in Zurich.
Project Leader and Associate Professor at the University of Copenhagen Peter Krustrup recaps the results: "Our research shows that soccer is a versatile and intense form of exercise that provides a positive effect on cardiovascular risk factors in a large group of untrained adult men and women," and continues: "Based on the results, soccer can be recommended as part of the treatment for high blood pressure and as broad-spectred prevention of cardiovascular diseases."
Small games, big gains
When untrained children, teens, adults and older people play soccer, their pulse rate remains high and they perform multiple intense actions like sprints, turns, kicks and tackles.
"Our analyses also showed that the pulse rate and activity profile is the same in small-sided games where only 4, 6, 8 or 14 people play. In other words, it is very easy to obtain a combination of cardio and strength training with soccer," concludes Krustrup
Research partner Lars Juel Andersen from the Clinic of Sport Cardiology at Gentofte Hospital, Denmark, believes that the results are good news for the millions of people worldwide, suffering from high blood pressure: "It is well known that physical inactivity is a substantial risk factor in developing cardiovascular diseases in itself, but it is new that a pleasurable team sport like soccer is effective in treating high blood pressure". Furthermore, associate professor Peter Riis Hansen from Gentofte Hospital suggests that football may have other favourable effects on the vascular system, namely a reduction of arterial stiffness, which has been associated with improved cardiovascular outcomes.
About the project
Led by Professors Peter Krustrup and Jens Bangsbo from Department of Exercise and Sports Sciences, University of Copenhagen, 50 researchers from seven countries have studied the physical, psychological and social aspects of soccer and the results are remarkable. A number of scientific articles from the project are published on 2 February 2010 at a seminar at the University of Copenhagen and later this month the Scandinavian Journal of Medicine and Science in Sports will publish a special edition issue entitled "Football for Health" containing 14 scientific articles from the soccer project. The research project has received funding from FIFA - Medical Assessment and Research Centre (F-MARC), The Danish Ministry of Culture, TrygFonden, United Federation of Danish Workers (3F), The Danish Football Association, Team Denmark and The Danish Sports Confederation.
Further research plans:
The researchers have specific plans to examine the effect of soccer on other patient groups such as people with diabetes II and cancer. The research group is also planning a follow-up study of the long-term effects of soccer on high blood pressure and preliminary stages of osteoporosis. A planned collaboration with an international network of researchers from, among others, England, Italy, Portugal, Switzerland, Germany, Norway, Sweden, USA, Kenya and Iran will examine the cardiovascular and muscular-skeletal effects of soccer and other ball games such as basketball, handball, volleyball and floorball on inactive and overweight children and inactive elderly people.
Tri-pepper blend burns calories
A new weight-loss supplement tested by the University of Oklahoma Health and Exercise Science Department has the potential to burn as many calories as a 20-minute walk, according to Joel T. Cramer, assistant professor of exercise physiology.
Cramer says General Nutrition Centers contracted with OU to test the weight-loss benefits of the nutritional supplement called the tri-pepper blend, which contains black pepper, caffeine and a concentrated form of capsaicin—the ingredient that makes red peppers hot. The OU study showed energy expenditures of three to six percent, results which are statistically significant enough to validate product weight-loss claims, Cramer said.
A group of participants in the study were given the supplement or a placebo followed by a metabolic rate test. The study measured oxygen consumed and carbon dioxide produced by participants to determine the arresting metabolic rate of each after receiving the supplements. The study confirmed the viability of the weight loss supplement.
OU has developed relationships within the nutritional supplement industry because of the department’s ability to provide research support needed for new product development. Since Cramer arrived at OU in 2005 with a model of funding for industry grants, departmental funds have increased to nearly $3 million. The outcome has been an increase in th
Cramer says General Nutrition Centers contracted with OU to test the weight-loss benefits of the nutritional supplement called the tri-pepper blend, which contains black pepper, caffeine and a concentrated form of capsaicin—the ingredient that makes red peppers hot. The OU study showed energy expenditures of three to six percent, results which are statistically significant enough to validate product weight-loss claims, Cramer said.
A group of participants in the study were given the supplement or a placebo followed by a metabolic rate test. The study measured oxygen consumed and carbon dioxide produced by participants to determine the arresting metabolic rate of each after receiving the supplements. The study confirmed the viability of the weight loss supplement.
OU has developed relationships within the nutritional supplement industry because of the department’s ability to provide research support needed for new product development. Since Cramer arrived at OU in 2005 with a model of funding for industry grants, departmental funds have increased to nearly $3 million. The outcome has been an increase in th
Thursday, January 28, 2010
Tea and Exercise May Affect Depression in Breast Cancer Patients
Breast cancer patients who exercise and drink tea on a regular basis may be less likely to suffer from depression than other patients, according to a new study led by Xiao Ou Shu, M.D., Ph.D., professor of Medicine, Vanderbilt-Ingram Cancer Center. Xiaoli Chen, M.D., a post-doctoral fellow, was first author of the study published in the January issue of the Journal of Clinical Oncology.
The study, conducted in collaboration with investigators from the Shanghai Institute of Preventive Medicine, examined 1,399 women enrolled in the Shanghai Breast Cancer Survival Study in China. Each woman was interviewed about her exercise and diet habits six months following a breast cancer diagnosis. The women were interviewed again approximately 18 months after diagnosis and they also reported on their depressive symptoms. Twenty-six percent of the women reported depression during the follow-up survey: 13.4 percent had mild depression and 12.6 percent had clinical depression.
Depression may reduce a patient’s quality of life, increase the length of hospital stays and affect compliance with cancer therapy.
“We found that all types of exercise decreased the risk for clinical depression,” said Shu. “Women who exercised for two or more hours per week, and those who expended more energy during exercise were less likely to have depression than women who did not exercise.”
Those patients who increased their exercise level during the follow-up period were 42 percent less likely to report overall depression. However, quitting exercise or reducing exercise was not related to increased depression.
Women also were questioned about their tea-drinking habits and investigators estimated the amount of tea consumed.
“Tea consumption after diagnosis was inversely associated with the risk for mild depression,” said Shu. “Lifetime tea consumption also was inversely related to depression. This is the first epidemiologic evidence that tea consumption may be associated with lower risk for depression among breast cancer survivors, although this was not a prespecified hypothesis. This inverse association was independent of other risk factors for depression.”
Since this study was conducted among Chinese women living in Shanghai, the type of tea most commonly consumed was green tea. Tea and its constituents contain high levels of caffeine and catechin polyphenols, which have demonstrated antioxidant, anticarcinogenic and anti-inflammatory properties.
The study is ongoing and will allow the investigators to evaluate how depression changes over time and to assess the long-term effects of exercise and tea consumption on depression among breast cancer survivors.
The study, conducted in collaboration with investigators from the Shanghai Institute of Preventive Medicine, examined 1,399 women enrolled in the Shanghai Breast Cancer Survival Study in China. Each woman was interviewed about her exercise and diet habits six months following a breast cancer diagnosis. The women were interviewed again approximately 18 months after diagnosis and they also reported on their depressive symptoms. Twenty-six percent of the women reported depression during the follow-up survey: 13.4 percent had mild depression and 12.6 percent had clinical depression.
Depression may reduce a patient’s quality of life, increase the length of hospital stays and affect compliance with cancer therapy.
“We found that all types of exercise decreased the risk for clinical depression,” said Shu. “Women who exercised for two or more hours per week, and those who expended more energy during exercise were less likely to have depression than women who did not exercise.”
Those patients who increased their exercise level during the follow-up period were 42 percent less likely to report overall depression. However, quitting exercise or reducing exercise was not related to increased depression.
Women also were questioned about their tea-drinking habits and investigators estimated the amount of tea consumed.
“Tea consumption after diagnosis was inversely associated with the risk for mild depression,” said Shu. “Lifetime tea consumption also was inversely related to depression. This is the first epidemiologic evidence that tea consumption may be associated with lower risk for depression among breast cancer survivors, although this was not a prespecified hypothesis. This inverse association was independent of other risk factors for depression.”
Since this study was conducted among Chinese women living in Shanghai, the type of tea most commonly consumed was green tea. Tea and its constituents contain high levels of caffeine and catechin polyphenols, which have demonstrated antioxidant, anticarcinogenic and anti-inflammatory properties.
The study is ongoing and will allow the investigators to evaluate how depression changes over time and to assess the long-term effects of exercise and tea consumption on depression among breast cancer survivors.
Alli Raises Blood Pressure, Weight, Low Carb Diet Better
A new review of existing research confirms that a weight-loss drug raises blood pressure, posing a risk to obese patients who hope to reduce hypertension by shedding pounds.
Many doctors assume that patients automatically lower their blood pressure when they become thinner, but that is not necessarily the case when they use drugs to lose weight, said review lead author Dr. Andrea Siebenhofer.
In the big picture, "anti-obesity drugs are no wonder pills and should be prescribed only if patients beg doctors for some tablets which help them to lose some weight," said Siebenhofer, a researcher at the Medical University of Graz in Austria.
The review authors examined research regarding three weight-loss drugs — orlistat, sibutramine and rimonabant. They looked for studies that lasted at least six months and compared patients with high blood pressure who took one of the drugs to those who took a placebo.
The analysis appears in the latest issue of The Cochrane Library, a publication of The Cochrane Collaboration, an international organization that evaluates medical research. Systematic reviews draw evidence-based conclusions about medical practice after considering both the content and quality of existing medical trials on a topic.
The researchers found no studies that met their criteria for patients who took rimonabant, known by the brand name Acomplia.
The drug is not available in the United States; in 2007, the Food and Drug Administration declined to approve its sale and asked its manufacturer to provide more information about its safety. In 2008, the manufacturer agreed to suspend its sale in Europe, amid reports that it heightened the risk of suicidal thoughts.
The review authors did find four studies examining each of the other two drugs, orlistat and sibutramine.
Orlistat, known by the brand names Xenical and Alli, is both an over-the-counter and a prescription drug in the United States. Sibutramine is a prescription drug sold under the brand name Meridia.
The researchers conducted a meta-analysis by combining the studies and adjusting the statistical results to account for their sizes.
In those treated with orlistat, blood pressure fell by an average of 2.5 mm Hg systolic and 1.9 mm Hg diastolic.
However, the diastolic blood pressure levels of patients who took sibutramine rose by 3.2 mm Hg, according to the meta-analysis.
Systolic blood pressure is the top number in a blood-pressure reading (like 120/80) while diastolic is the bottom number.
The review of sibutramine research had some limitations. The review authors only looked at two of the four studies into the drug because they believed the other two did not meet the criteria they had set for inclusion in the meta-analysis.
In addition, the researchers reported that the two studies they did include failed to provide enough information to allow them to calculate how the drug affected systolic blood pressure.
Carla Wolper, a member of the research faculty at New York Obesity Research Center at St. Luke's Hospital, said weight-loss drugs have a place in obesity treatment, but that it is important to prescribe them with care and use them in conjunction with other strategies.
A "smart dietician" is crucial to success, Wolper said, as long as he or she "helps people adjust their diet without making a 180-degree change and uses cognitive behavior therapy to challenge people's ideas" about eating.
Wolper acknowledged working on a drug company-funded study into orlistat.
Dr. Raj Padwal, an assistant professor at the University of Alberta in Canada, said the weight-loss drugs only result in modest amounts of weight loss — typically 6 to 11 pounds — but do improve cardiovascular health. Sibutramine is the exception because it raises blood pressure, he said, and a large study is underway to see if it affects death rates in patients.
Only about 2 percent of patients continue to use the drugs after two years and many find the amount of weight lost disappointing, Padwal said. Side effects are also a problem — orlistat can cause loose stools, for instance — and the drugs are expensive, he added.
"There are no magic pills," he said. "These pills may help a minority of people, and I've seen some people lose a lot of weight, but treatment must be supervised by a health-care provider with appropriate monitoring of parameters, such as blood pressure."
Siebenhofer A, et al. Long-term effects of weight-reducing drugs in hypertensive patients. Cochrane Database of Systematic Reviews 2009, Issue 3.
Low-carb diet effective at lowering blood pressure
In a head-to-head comparison, two popular weight loss methods proved equally effective at helping participants lose significant amounts of weight. But, in a surprising twist, a low-carbohydrate diet proved better at lowering blood pressure than the weight-loss drug orlistat, according to researchers at Veterans Affairs Medical Center and Duke University Medical Center.
The findings send an important message to hypertensive people trying to lose weight, says William S. Yancy, Jr., MD, lead author of the study in the Jan. 25 Archives of Internal Medicine, and an associate professor of medicine at Duke. "If people have high blood pressure and a weight problem, a low-carbohydrate diet might be a better option than a weight loss medication."
Yancy added, "It's important to know you can try a diet instead of medication and get the same weight loss results with fewer costs and potentially fewer side effects."
Studies had already indicated that a low-carbohydrate diet and prescription-strength orlistat combined with a low-fat diet are effective weight loss therapies. But the two common strategies had not been compared to each other, an important omission now that orlistat is available over-the-counter. In addition, few studies provide data on these treatments for overweight patients with chronic health issues.
That's what made these findings particularly interesting, says Yancy, a staff physician at the Durham VA where the research was conducted. The 146 overweight participants in the year-long study had a range of health problems typically associated with obesity -- diabetes, high blood pressure, high cholesterol and arthritis.
"Most participants in weight loss studies are healthy and don't have these problems," he said. "In fact they are often excluded if they do."
The average weight loss for both groups was nearly 10 percent of their body weight. "Not many studies are able to achieve that," says Yancy, who attributes the significant weight loss to the group counseling that was offered for 48 weeks. In fact, he says "people tolerated orlistat better than I expected. Orlistat use is often limited by gastro-intestinal side effects, but these can be avoided, or at least lessened, by following a low-fat diet closely. We counseled people on orlistat in our study fairly extensively about the low-fat diet."
In addition to achieving equal success at weight loss, the methods proved equally effective at improving cholesterol and glucose levels.
But Yancy said it was the difference in blood pressure results that was most surprising.
Nearly half (47%) of patients in the low-carbohydrate group had their blood pressure medication decreased or discontinued while only 21 percent of the orlistat plus low-fat diet group experienced a reduction in medication use. Systolic blood pressure dropped considerably in the low-carbohydrate group when compared to the orlistat plus low-fat diet group.
"I expected the weight loss to be considerable with both therapies but we were surprised to see blood pressure improve so much more with the low-carbohydrate diet than with orlistat," says Yancy, who says the mechanism is unclear. "While weight loss typically induces improvements in blood pressure, it may be that the low-carbohydrate diet has an additional effect." That physiologic effect may be the subject of future studies.
The bottom line, says Yancy, is that many diet options are proving effective at weight loss. But it's counseling patients on how to best follow the options that appears to be making the biggest impact. "It is clear now that several diet options can work, so people can be given a choice of different ways to lose weight. But more importantly, we need to find new ways to help people maintain their new lifestyle."
###
Many doctors assume that patients automatically lower their blood pressure when they become thinner, but that is not necessarily the case when they use drugs to lose weight, said review lead author Dr. Andrea Siebenhofer.
In the big picture, "anti-obesity drugs are no wonder pills and should be prescribed only if patients beg doctors for some tablets which help them to lose some weight," said Siebenhofer, a researcher at the Medical University of Graz in Austria.
The review authors examined research regarding three weight-loss drugs — orlistat, sibutramine and rimonabant. They looked for studies that lasted at least six months and compared patients with high blood pressure who took one of the drugs to those who took a placebo.
The analysis appears in the latest issue of The Cochrane Library, a publication of The Cochrane Collaboration, an international organization that evaluates medical research. Systematic reviews draw evidence-based conclusions about medical practice after considering both the content and quality of existing medical trials on a topic.
The researchers found no studies that met their criteria for patients who took rimonabant, known by the brand name Acomplia.
The drug is not available in the United States; in 2007, the Food and Drug Administration declined to approve its sale and asked its manufacturer to provide more information about its safety. In 2008, the manufacturer agreed to suspend its sale in Europe, amid reports that it heightened the risk of suicidal thoughts.
The review authors did find four studies examining each of the other two drugs, orlistat and sibutramine.
Orlistat, known by the brand names Xenical and Alli, is both an over-the-counter and a prescription drug in the United States. Sibutramine is a prescription drug sold under the brand name Meridia.
The researchers conducted a meta-analysis by combining the studies and adjusting the statistical results to account for their sizes.
In those treated with orlistat, blood pressure fell by an average of 2.5 mm Hg systolic and 1.9 mm Hg diastolic.
However, the diastolic blood pressure levels of patients who took sibutramine rose by 3.2 mm Hg, according to the meta-analysis.
Systolic blood pressure is the top number in a blood-pressure reading (like 120/80) while diastolic is the bottom number.
The review of sibutramine research had some limitations. The review authors only looked at two of the four studies into the drug because they believed the other two did not meet the criteria they had set for inclusion in the meta-analysis.
In addition, the researchers reported that the two studies they did include failed to provide enough information to allow them to calculate how the drug affected systolic blood pressure.
Carla Wolper, a member of the research faculty at New York Obesity Research Center at St. Luke's Hospital, said weight-loss drugs have a place in obesity treatment, but that it is important to prescribe them with care and use them in conjunction with other strategies.
A "smart dietician" is crucial to success, Wolper said, as long as he or she "helps people adjust their diet without making a 180-degree change and uses cognitive behavior therapy to challenge people's ideas" about eating.
Wolper acknowledged working on a drug company-funded study into orlistat.
Dr. Raj Padwal, an assistant professor at the University of Alberta in Canada, said the weight-loss drugs only result in modest amounts of weight loss — typically 6 to 11 pounds — but do improve cardiovascular health. Sibutramine is the exception because it raises blood pressure, he said, and a large study is underway to see if it affects death rates in patients.
Only about 2 percent of patients continue to use the drugs after two years and many find the amount of weight lost disappointing, Padwal said. Side effects are also a problem — orlistat can cause loose stools, for instance — and the drugs are expensive, he added.
"There are no magic pills," he said. "These pills may help a minority of people, and I've seen some people lose a lot of weight, but treatment must be supervised by a health-care provider with appropriate monitoring of parameters, such as blood pressure."
Siebenhofer A, et al. Long-term effects of weight-reducing drugs in hypertensive patients. Cochrane Database of Systematic Reviews 2009, Issue 3.
Low-carb diet effective at lowering blood pressure
In a head-to-head comparison, two popular weight loss methods proved equally effective at helping participants lose significant amounts of weight. But, in a surprising twist, a low-carbohydrate diet proved better at lowering blood pressure than the weight-loss drug orlistat, according to researchers at Veterans Affairs Medical Center and Duke University Medical Center.
The findings send an important message to hypertensive people trying to lose weight, says William S. Yancy, Jr., MD, lead author of the study in the Jan. 25 Archives of Internal Medicine, and an associate professor of medicine at Duke. "If people have high blood pressure and a weight problem, a low-carbohydrate diet might be a better option than a weight loss medication."
Yancy added, "It's important to know you can try a diet instead of medication and get the same weight loss results with fewer costs and potentially fewer side effects."
Studies had already indicated that a low-carbohydrate diet and prescription-strength orlistat combined with a low-fat diet are effective weight loss therapies. But the two common strategies had not been compared to each other, an important omission now that orlistat is available over-the-counter. In addition, few studies provide data on these treatments for overweight patients with chronic health issues.
That's what made these findings particularly interesting, says Yancy, a staff physician at the Durham VA where the research was conducted. The 146 overweight participants in the year-long study had a range of health problems typically associated with obesity -- diabetes, high blood pressure, high cholesterol and arthritis.
"Most participants in weight loss studies are healthy and don't have these problems," he said. "In fact they are often excluded if they do."
The average weight loss for both groups was nearly 10 percent of their body weight. "Not many studies are able to achieve that," says Yancy, who attributes the significant weight loss to the group counseling that was offered for 48 weeks. In fact, he says "people tolerated orlistat better than I expected. Orlistat use is often limited by gastro-intestinal side effects, but these can be avoided, or at least lessened, by following a low-fat diet closely. We counseled people on orlistat in our study fairly extensively about the low-fat diet."
In addition to achieving equal success at weight loss, the methods proved equally effective at improving cholesterol and glucose levels.
But Yancy said it was the difference in blood pressure results that was most surprising.
Nearly half (47%) of patients in the low-carbohydrate group had their blood pressure medication decreased or discontinued while only 21 percent of the orlistat plus low-fat diet group experienced a reduction in medication use. Systolic blood pressure dropped considerably in the low-carbohydrate group when compared to the orlistat plus low-fat diet group.
"I expected the weight loss to be considerable with both therapies but we were surprised to see blood pressure improve so much more with the low-carbohydrate diet than with orlistat," says Yancy, who says the mechanism is unclear. "While weight loss typically induces improvements in blood pressure, it may be that the low-carbohydrate diet has an additional effect." That physiologic effect may be the subject of future studies.
The bottom line, says Yancy, is that many diet options are proving effective at weight loss. But it's counseling patients on how to best follow the options that appears to be making the biggest impact. "It is clear now that several diet options can work, so people can be given a choice of different ways to lose weight. But more importantly, we need to find new ways to help people maintain their new lifestyle."
###
alli Proven to Reduce Visceral Fat, a Dangerous Fat Linked to Many Life-Threatening Diseases
New studies show that overweight and obese people using alli® (orlistat 60 mg) with a reduced calorie, lower-fat diet can significantly reduce weight, visceral fat, and waist circumference and therefore may reduce their risk of type 2 diabetes, hypertension, heart disease and stroke.1,2 The studies were presented at the 1st International Congress on Abdominal Obesity in Hong Kong earlier today.
alli is the only FDA-approved OTC weight loss aid that is clinically proven to boost weight loss by 50 percent and significantly reduce excess visceral fat.3 Working in the digestive tract, alli prevents about 25 percent of the fat that a person eats from being absorbed.3
Visceral fat is a dangerous type of fat that surrounds the vital organs in the abdomen and when present in excess disrupts the normal functioning of organs, increasing the risk of life-threatening diseases.4-12 Even modest weight loss can result in significant reductions in visceral fat and substantially improve health.14-17 In fact, when losing weight, visceral fat is among the first fat lost, which is associated with noticeable health benefits such as reductions in total cholesterol and low-density lipoprotein (LDL).21 This helps reduce the risk of type 2 diabetes, hypertension, heart disease and stroke.4-9 It is these health complications that have a high personal and societal toll and impact in the global obesity epidemic.
"Although most individuals try to lose weight to improve their appearance, it's important to help them understand that losing excess fat reduces their risks of life-threatening diseases,” said Jeanine Albu, M.D., Senior Attending in Medicine, Associate Chief of the Division of Endocrinology, Diabetes and Nutrition and the Chief of the Metabolism and Diabetes Clinic at the St. Luke’s-Roosevelt Hospital Center in New York.
“We need to raise awareness of the direct link between visceral fat on the inside and heart disease and diabetes,” said Dr. Albu. “Through healthy eating, keeping active and treatments such as alli, people can lose 5 to 10 percent of total body weight – including visceral fat – and achieve and maintain their healthy weight."
In two of the studies presented at the congress, alli was evaluated to determine its effect on excess visceral fat. This new body of evidence proves that alli significantly reduces weight and dangerous visceral fat to help people improve their health.1,2
The Visceral Fat Imaging Study_The three-month Visceral Fat Imaging Study demonstrated that alli reduced total body weight by 5.6 percent and visceral fat by 10.6 percent versus amounts at the start of the study in overweight and obese adults on a reduced calorie, lower-fat diet (P<0.0225).1 Carried out at Europe’s largest imaging center, the Clinical Imaging Centre in Hammersmith Hospital, UK, the study used MRI technology that showed changes taking place inside people’s bodies as they lost weight in a unique way.
Twenty-six study participants were counseled to follow a reduced calorie, lower-fat diet, and then took alli three times per day for 12 weeks. Results also showed that at week 12 alli significantly reduced waist circumference (the measurement around the waistline), the best practical way to assess visceral fat, by 5 cm (2 inches).1,18-20
The Visceral Fat Multi-Center Study_In the six-month Visceral Fat Multi-Center Study, overweight and obese adults receiving alli while on a reduced calorie, lower-fat diet had significantly greater improvements in visceral fat than those treated with diet alone. 2
In this study, 123 participants were randomly assigned to receive either alli three times per day or a placebo, along with recommendations to follow a reduced calorie, lower-fat diet, for 24 weeks. At week 24, statistically significant reductions in visceral fat and body weight were observed in both groups; however, the reduction was significantly higher among patients taking alli. Mean reductions in visceral fat were 15.66 percent for alli versus 9.39 percent for placebo (P<0.0001); mean reductions in body weight were 5.96 kg versus 3.91 kg, respectively (P<0.05).2
Overweight and obese people enrolled in the Visceral Fat Imaging Study and Visceral Fat Multi-Center Study had a body mass index (BMI) of 25-35 kg/m2, with a waist circumference greater than 88 cm (34.64 inches) for women or 102 cm (40.16 inches) for men at the start of the studies.1,2 Use of alli in both studies was shown to be generally well tolerated and consistent with the known safety profile.1,2
alli is marketed by GlaxoSmithKline Consumer Healthcare for use by overweight adults along with a reduced calorie, lower-fat diet. People interested in losing weight can access interactive tools, lower-fat recipes, physical activity tips and other useful information for leading a healthy life at www.myalli.com.
*Note to editors
For European interest, since overweight and obese is defined as BMI ≥28 kg/m2, post-hoc analysis for BMI ≥28 kg/m2 also found reductions in body weight and waist circumference (N=22, P<0.0001 for both) and VAT (N=19, P=0.0336).2
About alli®_alli is the only FDA-approved weight-loss product available to overweight adults, 18 years or older, without a prescription. alli is a clinically-proven product used with a comprehensive individualized action plan. People who use alli can lose 50 percent more weight than diet alone. The alli program encourages gradual weight loss, known by experts as the best way to lose weight. alli (60 mg orlistat capsules) is safe and effective when used as directed.
The alli plan was developed by nutritional and weight management experts who understand the struggle to lose weight. The alli program, which includes a healthy, balanced diet, regular physical activity and alli capsules available in 60-capsule and 90-capsule educational starter packs. alli works by blocking about 25 percent of fat in the foods eaten to reduce the amount of fat and calories absorbed. alli is non-systemic and well-tolerated.
www.myalli.com
About GlaxoSmithKline Consumer Healthcare_GlaxoSmithKline Consumer Healthcare is one of the world's largest over-the-counter consumer healthcare products companies. Its more than 30 well-known brands include the leading smoking cessation products, Nicorette®, NicoDerm® CQ and Commit® as well as many medicine cabinet staples, including Aquafresh®, Sensodyne®, Tums® and Breathe Right®.
About GlaxoSmithKline_GlaxoSmithKline -- one of the world's leading research-based pharmaceutical and healthcare companies -- is committed to improving the quality of human life by enabling people to do more, feel better and live longer. For company information visit: http://www.gsk.com.
Cautionary statement regarding forward-looking statements_Under the safe harbor provisions of the U.S. Private Securities Litigation Reform Act of 1995, GSK cautions investors that any forward-looking statements or projections made by GSK, including those made in this announcement, are subject to risks and uncertainties that may cause actual results to differ materially from those projected. Factors that may affect GSK' s operations are described under 'Risk Factors' in the 'Business Review' in the company' s Annual Report on Form 20-F for 2008.
References:
1.Beaver J, Bell JD, Thomas EL et al. Orlistat 60 mg in conjunction with diet provides significant reduction in visceral adipose tissue. Poster presented at: 1st International Congress on Abdominal Obesity, 2009, Hong Kong._2.Greenway F, Smith SR, Murray K et al. Orlistat 60 mg demonstrates a significant reduction in visceral adipose tissue at 24 weeks compared with placebo. Poster presented at: 1st International Congress on Abdominal Obesity, 2009, Hong Kong._3.alli Product Label. GlaxoSmithKline Consumer Health._4. Wang Y et al. Comparison of abdominal adiposity and overall obesity in predicting risk of type 2 diabetes among men. Am J Clin Nutr. 2005, 81: 555-63._5. Chan J et al. Obesity, fat distribution, and weight gain as risk factors for clinical diabetes in men. Diabetes Care 1994;17(9): 961-969._6. Larsson B et al. Abdominal adipose tissue distribution, obesity, and risk of cardiovascular disease and death: 13 year follow-up of participants in the study of men born in 1913. Br Med J. 1984; 288: 1401-4._7. Sironi AM et al. Visceral Fat in Hypertension: Influence on Insulin Resistance and ß-Cell function. Hypertension 2004 ;44;127–133._8. Lapidus L et al. Distribution of adipose tissue and risk of cardiovascular disease and death: a 12-year follow-up of participants in the population study of women In Gothenburg, Sweden. Br Med J. 1984; 289: 1257-61._9. Yusuf S et al. Effect of potentially modifiable risk factors associated with myocardial infarction in 52 countries (the INTERHEART study): case-control study. Lancet 2004, 364: 937-952._10. Pouliot MC et al. Visceral obesity in men. Associations with glucose tolerance, plasma insulin, and lipoprotein levels. Diabetes 1992, 41: 826-34._11. Lean ME. Impairment of health and quality of life in people with large waist circumference. Lancet 1998; 351(9106): 853-6._12. Mathieu P et al. Visceral Obesity: The Link Among Inflammation, Hypertension, and Cardiovascular Disease. Hypertension 2009; 53:577-584_13. Purnell J et al. Effect of Weight Loss with Reduction of Intra-Abdominal Fat on Lipid Metabolism in Older Men. J Clin Endocrinol Metab. 2000; 85: 977–82._14. Rice B et al. Effects of Aerobic or Resistance Exercise and/or Diet on Glucose Tolerance and Plasma Insulin Levels in Obese Men. Diabetes Care 1999; 22(5): 684-91._15. Goodpaster B et al. Effects of weight loss on regional fat distribution and insulin sensitivity in obesity. Diabetes 1999; 48: 839-47._16. Ross R et al. Reduction in Obesity and Related Comorbid Conditions after Diet-Induced Weight Loss or Exercise-Induced Weight Loss in Men A Randomized, Controlled Trial. Ann Intern Med. 2000; 133: 92-103._17. Ross A et al. Exercise-Induced Reduction in Obesity and Insulin Resistance in Women: a Randomized Controlled Trial. Obesity Research 2004;12: 789–798._18. Lean ME, et al. Waist circumference as a measure for indicating need for weight management. British Med J. 1995;311:158-61._19. Pouliot MC, et al. Waist circumference and abdominal sagittal diameter: best simple anthropometric indexes of abdominal visceral adipose tissue accumulation and related cardiovascular risk in men and women. Am J Cardiol. 1994;73(7):460-8._20. NHLBI Obesity Education Initiative. The Practical Guide Identification, Evaluation, and Treatment of Overweight and Obesity in Adults. http://www.nhlbi.nih.gov/guidelines/obesity/prctgd_c.pdf. Accessed 02/11/2009._21. Weight Control Information Network. Statistics Related to Overweight and Obesity. http://www.win.niddk.nih.gov/statistics/index.htm. Accessed 8 January 2010
alli is the only FDA-approved OTC weight loss aid that is clinically proven to boost weight loss by 50 percent and significantly reduce excess visceral fat.3 Working in the digestive tract, alli prevents about 25 percent of the fat that a person eats from being absorbed.3
Visceral fat is a dangerous type of fat that surrounds the vital organs in the abdomen and when present in excess disrupts the normal functioning of organs, increasing the risk of life-threatening diseases.4-12 Even modest weight loss can result in significant reductions in visceral fat and substantially improve health.14-17 In fact, when losing weight, visceral fat is among the first fat lost, which is associated with noticeable health benefits such as reductions in total cholesterol and low-density lipoprotein (LDL).21 This helps reduce the risk of type 2 diabetes, hypertension, heart disease and stroke.4-9 It is these health complications that have a high personal and societal toll and impact in the global obesity epidemic.
"Although most individuals try to lose weight to improve their appearance, it's important to help them understand that losing excess fat reduces their risks of life-threatening diseases,” said Jeanine Albu, M.D., Senior Attending in Medicine, Associate Chief of the Division of Endocrinology, Diabetes and Nutrition and the Chief of the Metabolism and Diabetes Clinic at the St. Luke’s-Roosevelt Hospital Center in New York.
“We need to raise awareness of the direct link between visceral fat on the inside and heart disease and diabetes,” said Dr. Albu. “Through healthy eating, keeping active and treatments such as alli, people can lose 5 to 10 percent of total body weight – including visceral fat – and achieve and maintain their healthy weight."
In two of the studies presented at the congress, alli was evaluated to determine its effect on excess visceral fat. This new body of evidence proves that alli significantly reduces weight and dangerous visceral fat to help people improve their health.1,2
The Visceral Fat Imaging Study_The three-month Visceral Fat Imaging Study demonstrated that alli reduced total body weight by 5.6 percent and visceral fat by 10.6 percent versus amounts at the start of the study in overweight and obese adults on a reduced calorie, lower-fat diet (P<0.0225).1 Carried out at Europe’s largest imaging center, the Clinical Imaging Centre in Hammersmith Hospital, UK, the study used MRI technology that showed changes taking place inside people’s bodies as they lost weight in a unique way.
Twenty-six study participants were counseled to follow a reduced calorie, lower-fat diet, and then took alli three times per day for 12 weeks. Results also showed that at week 12 alli significantly reduced waist circumference (the measurement around the waistline), the best practical way to assess visceral fat, by 5 cm (2 inches).1,18-20
The Visceral Fat Multi-Center Study_In the six-month Visceral Fat Multi-Center Study, overweight and obese adults receiving alli while on a reduced calorie, lower-fat diet had significantly greater improvements in visceral fat than those treated with diet alone. 2
In this study, 123 participants were randomly assigned to receive either alli three times per day or a placebo, along with recommendations to follow a reduced calorie, lower-fat diet, for 24 weeks. At week 24, statistically significant reductions in visceral fat and body weight were observed in both groups; however, the reduction was significantly higher among patients taking alli. Mean reductions in visceral fat were 15.66 percent for alli versus 9.39 percent for placebo (P<0.0001); mean reductions in body weight were 5.96 kg versus 3.91 kg, respectively (P<0.05).2
Overweight and obese people enrolled in the Visceral Fat Imaging Study and Visceral Fat Multi-Center Study had a body mass index (BMI) of 25-35 kg/m2, with a waist circumference greater than 88 cm (34.64 inches) for women or 102 cm (40.16 inches) for men at the start of the studies.1,2 Use of alli in both studies was shown to be generally well tolerated and consistent with the known safety profile.1,2
alli is marketed by GlaxoSmithKline Consumer Healthcare for use by overweight adults along with a reduced calorie, lower-fat diet. People interested in losing weight can access interactive tools, lower-fat recipes, physical activity tips and other useful information for leading a healthy life at www.myalli.com.
*Note to editors
For European interest, since overweight and obese is defined as BMI ≥28 kg/m2, post-hoc analysis for BMI ≥28 kg/m2 also found reductions in body weight and waist circumference (N=22, P<0.0001 for both) and VAT (N=19, P=0.0336).2
About alli®_alli is the only FDA-approved weight-loss product available to overweight adults, 18 years or older, without a prescription. alli is a clinically-proven product used with a comprehensive individualized action plan. People who use alli can lose 50 percent more weight than diet alone. The alli program encourages gradual weight loss, known by experts as the best way to lose weight. alli (60 mg orlistat capsules) is safe and effective when used as directed.
The alli plan was developed by nutritional and weight management experts who understand the struggle to lose weight. The alli program, which includes a healthy, balanced diet, regular physical activity and alli capsules available in 60-capsule and 90-capsule educational starter packs. alli works by blocking about 25 percent of fat in the foods eaten to reduce the amount of fat and calories absorbed. alli is non-systemic and well-tolerated.
www.myalli.com
About GlaxoSmithKline Consumer Healthcare_GlaxoSmithKline Consumer Healthcare is one of the world's largest over-the-counter consumer healthcare products companies. Its more than 30 well-known brands include the leading smoking cessation products, Nicorette®, NicoDerm® CQ and Commit® as well as many medicine cabinet staples, including Aquafresh®, Sensodyne®, Tums® and Breathe Right®.
About GlaxoSmithKline_GlaxoSmithKline -- one of the world's leading research-based pharmaceutical and healthcare companies -- is committed to improving the quality of human life by enabling people to do more, feel better and live longer. For company information visit: http://www.gsk.com.
Cautionary statement regarding forward-looking statements_Under the safe harbor provisions of the U.S. Private Securities Litigation Reform Act of 1995, GSK cautions investors that any forward-looking statements or projections made by GSK, including those made in this announcement, are subject to risks and uncertainties that may cause actual results to differ materially from those projected. Factors that may affect GSK' s operations are described under 'Risk Factors' in the 'Business Review' in the company' s Annual Report on Form 20-F for 2008.
References:
1.Beaver J, Bell JD, Thomas EL et al. Orlistat 60 mg in conjunction with diet provides significant reduction in visceral adipose tissue. Poster presented at: 1st International Congress on Abdominal Obesity, 2009, Hong Kong._2.Greenway F, Smith SR, Murray K et al. Orlistat 60 mg demonstrates a significant reduction in visceral adipose tissue at 24 weeks compared with placebo. Poster presented at: 1st International Congress on Abdominal Obesity, 2009, Hong Kong._3.alli Product Label. GlaxoSmithKline Consumer Health._4. Wang Y et al. Comparison of abdominal adiposity and overall obesity in predicting risk of type 2 diabetes among men. Am J Clin Nutr. 2005, 81: 555-63._5. Chan J et al. Obesity, fat distribution, and weight gain as risk factors for clinical diabetes in men. Diabetes Care 1994;17(9): 961-969._6. Larsson B et al. Abdominal adipose tissue distribution, obesity, and risk of cardiovascular disease and death: 13 year follow-up of participants in the study of men born in 1913. Br Med J. 1984; 288: 1401-4._7. Sironi AM et al. Visceral Fat in Hypertension: Influence on Insulin Resistance and ß-Cell function. Hypertension 2004 ;44;127–133._8. Lapidus L et al. Distribution of adipose tissue and risk of cardiovascular disease and death: a 12-year follow-up of participants in the population study of women In Gothenburg, Sweden. Br Med J. 1984; 289: 1257-61._9. Yusuf S et al. Effect of potentially modifiable risk factors associated with myocardial infarction in 52 countries (the INTERHEART study): case-control study. Lancet 2004, 364: 937-952._10. Pouliot MC et al. Visceral obesity in men. Associations with glucose tolerance, plasma insulin, and lipoprotein levels. Diabetes 1992, 41: 826-34._11. Lean ME. Impairment of health and quality of life in people with large waist circumference. Lancet 1998; 351(9106): 853-6._12. Mathieu P et al. Visceral Obesity: The Link Among Inflammation, Hypertension, and Cardiovascular Disease. Hypertension 2009; 53:577-584_13. Purnell J et al. Effect of Weight Loss with Reduction of Intra-Abdominal Fat on Lipid Metabolism in Older Men. J Clin Endocrinol Metab. 2000; 85: 977–82._14. Rice B et al. Effects of Aerobic or Resistance Exercise and/or Diet on Glucose Tolerance and Plasma Insulin Levels in Obese Men. Diabetes Care 1999; 22(5): 684-91._15. Goodpaster B et al. Effects of weight loss on regional fat distribution and insulin sensitivity in obesity. Diabetes 1999; 48: 839-47._16. Ross R et al. Reduction in Obesity and Related Comorbid Conditions after Diet-Induced Weight Loss or Exercise-Induced Weight Loss in Men A Randomized, Controlled Trial. Ann Intern Med. 2000; 133: 92-103._17. Ross A et al. Exercise-Induced Reduction in Obesity and Insulin Resistance in Women: a Randomized Controlled Trial. Obesity Research 2004;12: 789–798._18. Lean ME, et al. Waist circumference as a measure for indicating need for weight management. British Med J. 1995;311:158-61._19. Pouliot MC, et al. Waist circumference and abdominal sagittal diameter: best simple anthropometric indexes of abdominal visceral adipose tissue accumulation and related cardiovascular risk in men and women. Am J Cardiol. 1994;73(7):460-8._20. NHLBI Obesity Education Initiative. The Practical Guide Identification, Evaluation, and Treatment of Overweight and Obesity in Adults. http://www.nhlbi.nih.gov/guidelines/obesity/prctgd_c.pdf. Accessed 02/11/2009._21. Weight Control Information Network. Statistics Related to Overweight and Obesity. http://www.win.niddk.nih.gov/statistics/index.htm. Accessed 8 January 2010
It's Better to Eat a Low Carb Meal After Exercise
Many of the health benefits of aerobic exercise are due to the most recent exercise session (rather than weeks, months and even years of exercise training), and the nature of these benefits can be greatly affected by the food we eat afterwards, according to a study published in the Journal of Applied Physiology.
“Differences in what you eat after exercise produce different effects on the body’s metabolism,” said the study’s senior author, Jeffrey F. Horowitz of the University of Michigan. This study follows up on several previous studies that demonstrate that many health benefits of exercise are transient: one exercise session produces benefits to the body that taper off, generally within hours or a few days.
“Many of the improvements in metabolic health associated with exercise stem largely from the most recent session of exercise, rather than from an increase in ‘fitness’ per se,” Dr. Horowitz said. “But exercise doesn’t occur in a vacuum, and it is very important to look at both the effects of exercise and what you’re eating after exercise.”
Specifically, the study found that exercise enhanced insulin sensitivity, particularly when meals eaten after the exercise session contained relatively low carbohydrate content. Enhanced insulin sensitivity means that it is easier for the body to take up sugar from the blood stream into tissues like muscles, where it can be stored or used as fuel. Impaired insulin sensitivity (i.e., “insulin resistance”) is a hallmark of Type II diabetes, as well as being a major risk factor for other chronic diseases, such as heart disease.
Interestingly, when the research subjects in this study ate relatively low-calorie meals after exercise, this did not improve insulin sensitivity any more than when they ate enough calories to match what they expended during exercise. This suggests that you don’t have to starve yourself after exercise to still reap some of the important health benefits.
The paper, “Energy deficit after exercise augments lipid mobilization but does not contribute to the exercise-induced increase in insulin sensitivity,” appears in the online edition of the journal.
Study Design
The study included nine healthy sedentary men, all around 28-30 years old. They spent four separate sessions in the Michigan Clinical Research Unit in the University of Michigan Hospital. Each session lasted for approximately 29 hours. They fasted overnight before attending each session, which began in the morning.
The four hospital visits differed primarily by the meals eaten after exercise. The following describes the four different visits:
1. They did not exercise and ate meals to match their daily calorie expenditure. This was the control trial.
2. They exercised for approximately 90 min at moderate intensity, and then ate meals that matched their caloric expenditure. The carbohydrate, fat, and protein content of these meals were also appropriately balanced to match their expenditure.
3. They exercised for approximately 90 min at moderate intensity and then ate meals with relatively low carbohydrate content, but they ate enough total calories to match their calorie expenditure. This reduced-carbohydrate meal contained about 200 grams of carbohydrate, less than half the carbohydrate content of the balanced meal.
4. They exercised for approximately 90 min at moderate intensity and then ate relatively low-calorie meals, that is, meals that provided less energy than was expended (about one-third fewer calories than the meals in the other two exercise trials). These meals contained a relatively high carbohydrate content to replace the carbohydrate “burned” during exercise.
The exercise was performed on a stationary bicycle and a treadmill. The order in which the participants did the trials was randomized.
In the three exercise trials, there was a trend for an increase in insulin sensitivity. However, when participants ate less carbohydrate after exercise, this enhanced insulin sensitivity significantly more. Although weight loss is important for improving metabolic health in overweight and obese people, these results suggests that people can still reap some important health benefits from exercise without undereating or losing weight, Dr. Horowitz said.
The study also reinforces the growing body of evidence that each exercise session can affect the body’s physiology and also that differences in what you eat after exercise can produce different physiological changes.
“Differences in what you eat after exercise produce different effects on the body’s metabolism,” said the study’s senior author, Jeffrey F. Horowitz of the University of Michigan. This study follows up on several previous studies that demonstrate that many health benefits of exercise are transient: one exercise session produces benefits to the body that taper off, generally within hours or a few days.
“Many of the improvements in metabolic health associated with exercise stem largely from the most recent session of exercise, rather than from an increase in ‘fitness’ per se,” Dr. Horowitz said. “But exercise doesn’t occur in a vacuum, and it is very important to look at both the effects of exercise and what you’re eating after exercise.”
Specifically, the study found that exercise enhanced insulin sensitivity, particularly when meals eaten after the exercise session contained relatively low carbohydrate content. Enhanced insulin sensitivity means that it is easier for the body to take up sugar from the blood stream into tissues like muscles, where it can be stored or used as fuel. Impaired insulin sensitivity (i.e., “insulin resistance”) is a hallmark of Type II diabetes, as well as being a major risk factor for other chronic diseases, such as heart disease.
Interestingly, when the research subjects in this study ate relatively low-calorie meals after exercise, this did not improve insulin sensitivity any more than when they ate enough calories to match what they expended during exercise. This suggests that you don’t have to starve yourself after exercise to still reap some of the important health benefits.
The paper, “Energy deficit after exercise augments lipid mobilization but does not contribute to the exercise-induced increase in insulin sensitivity,” appears in the online edition of the journal.
Study Design
The study included nine healthy sedentary men, all around 28-30 years old. They spent four separate sessions in the Michigan Clinical Research Unit in the University of Michigan Hospital. Each session lasted for approximately 29 hours. They fasted overnight before attending each session, which began in the morning.
The four hospital visits differed primarily by the meals eaten after exercise. The following describes the four different visits:
1. They did not exercise and ate meals to match their daily calorie expenditure. This was the control trial.
2. They exercised for approximately 90 min at moderate intensity, and then ate meals that matched their caloric expenditure. The carbohydrate, fat, and protein content of these meals were also appropriately balanced to match their expenditure.
3. They exercised for approximately 90 min at moderate intensity and then ate meals with relatively low carbohydrate content, but they ate enough total calories to match their calorie expenditure. This reduced-carbohydrate meal contained about 200 grams of carbohydrate, less than half the carbohydrate content of the balanced meal.
4. They exercised for approximately 90 min at moderate intensity and then ate relatively low-calorie meals, that is, meals that provided less energy than was expended (about one-third fewer calories than the meals in the other two exercise trials). These meals contained a relatively high carbohydrate content to replace the carbohydrate “burned” during exercise.
The exercise was performed on a stationary bicycle and a treadmill. The order in which the participants did the trials was randomized.
In the three exercise trials, there was a trend for an increase in insulin sensitivity. However, when participants ate less carbohydrate after exercise, this enhanced insulin sensitivity significantly more. Although weight loss is important for improving metabolic health in overweight and obese people, these results suggests that people can still reap some important health benefits from exercise without undereating or losing weight, Dr. Horowitz said.
The study also reinforces the growing body of evidence that each exercise session can affect the body’s physiology and also that differences in what you eat after exercise can produce different physiological changes.
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