Ω
In mice models of breast cancer, researchers at the Georgetown Lombardi Comprehensive Cancer Center, a part of Georgetown University Medical Center, found that vitamin D significantly reduced development of estrogen receptor-positive (ER+) breast cancer both in lean and obese mice, but had no beneficial effect in estrogen receptor-negative (ER-) cancer. In fact, obese mice destined to develop ER- breast cancer were clearly worse off than lean ER- mice if they were given vitamin D in their diet.
The researchers, who will present their study at the American Association for Cancer Research (AACR) 102nd Annual Meeting 2011, also found that vitamin D reversed insulin resistance in obese mice, no matter which breast cancer subtype they later developed. In lean mice, however, there was no evidence that vitamin D increased insulin sensitivity.
"Use of vitamin D supplementation is clearly tricky. In the many studies that have been done studying the effect of vitamin D in different cancer types, there is no straight link between use and benefit," says the study's lead investigator, Leena Hilakivi-Clarke, Ph.D., a professor in the Department of Oncology.
For example, in the colon, vitamin D seems to reduce the risk of cancer development, but it may not have any effect on later stage colon cancer. There is also concern that vitamin D may increase the risk of prostate, esophagus and pancreatic cancer. In work she has conducted in endometrial cancer, Hilakivi-Clarke found that although vitamin D was not beneficial in lean mice, in obese animals it reverses both early and advanced stages of the cancer.
"This is not a vitamin that should be taken lightly," she cautions. "People need sufficient amounts because it has beneficial effects for overall health that have nothing to do with preventing cancer. But for those who want to boost their use of vitamin D, it is important that they have their individual levels tested by a physician, and that they discuss their desire to use supplements."
Monday, April 4, 2011
Aspirin may lower the risk of pancreatic cancer
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The use of aspirin at least once per month is associated with a significant decrease in pancreatic cancer risk, according to results of a large case-control study presented at the AACR 102nd Annual Meeting 2011.
Xiang-Lin Tan, Ph.D., M.D., a research fellow at Mayo Clinic in Rochester, Minn., said the findings from this large collaborative study are preliminary and do not encourage widespread use of aspirin for this purpose.
"The results are not meant to suggest everyone should start taking aspirin once monthly to reduce their risk of pancreatic cancer," said Tan. "Individuals should discuss use of aspirin with their physicians because the drug carries some side effects."
For the current study, Tan and colleagues enrolled 904 patients who had documented pancreatic cancer and compared them with 1,224 healthy patients. All patients were at least 55 years old and reported their use of aspirin, NSAIDs and acetaminophen by questionnaire.
Results showed that people who took aspirin at least one day during a month had a 26 percent decreased risk of pancreatic cancer compared to those who did not take aspirin regularly. The effect was also found for those who took low-dose aspirin for heart disease prevention at 35 percent lower risk, according to Tan.
The researchers did not see a benefit from non-aspirin NSAIDs or acetaminophen. "This provides additional evidence that aspirin may have chemoprevention activity against pancreatic cancer," said Tan. He added that more data must be gathered before we can prove a real benefit.
###
The use of aspirin at least once per month is associated with a significant decrease in pancreatic cancer risk, according to results of a large case-control study presented at the AACR 102nd Annual Meeting 2011.
Xiang-Lin Tan, Ph.D., M.D., a research fellow at Mayo Clinic in Rochester, Minn., said the findings from this large collaborative study are preliminary and do not encourage widespread use of aspirin for this purpose.
"The results are not meant to suggest everyone should start taking aspirin once monthly to reduce their risk of pancreatic cancer," said Tan. "Individuals should discuss use of aspirin with their physicians because the drug carries some side effects."
For the current study, Tan and colleagues enrolled 904 patients who had documented pancreatic cancer and compared them with 1,224 healthy patients. All patients were at least 55 years old and reported their use of aspirin, NSAIDs and acetaminophen by questionnaire.
Results showed that people who took aspirin at least one day during a month had a 26 percent decreased risk of pancreatic cancer compared to those who did not take aspirin regularly. The effect was also found for those who took low-dose aspirin for heart disease prevention at 35 percent lower risk, according to Tan.
The researchers did not see a benefit from non-aspirin NSAIDs or acetaminophen. "This provides additional evidence that aspirin may have chemoprevention activity against pancreatic cancer," said Tan. He added that more data must be gathered before we can prove a real benefit.
###
Exercise may prevent stress on telomeres, a measure of cell health
Ω
UCSF scientists are reporting several studies showing that psychological stress leads to shorter telomeres – the protective caps on the ends of chromosomes that are a measure of cell age and, thus, health. The findings also suggest that exercise may prevent this damage.
The team focused on three groups: post-menopausal women who were the primary caregivers for a family member with dementia; young to middle-aged adults with post-traumatic stress disorder; and healthy, non-smoking women ages 50 to 65 years.
They examined telomeres in leukocytes, or white blood cells, of the immune system, which defends the body against both infectious agents and cell damage.
"Our findings suggest that traumatic and chronic stressful life events are associated with shortening of telomeres in cells of the immune system, but that physical activity may moderate this impact," said co-author Jue Lin, PhD, associate research biochemist in the laboratory of senior author and Nobel laureate Elizabeth Blackburn, PhD, professor of biochemistry and biophysics at UCSF.
Lin presented the findings in a poster session on Monday, April 4, 2011, at the AACR 102nd Annual Meeting 2011.
Telomeres are tiny units of DNA at the ends of chromosomes that protect and stabilize chromosomes. Every time a cell divides, some telomeres drop off. After a certain number of cell divisions, which varies depending on the cell type, the telomeres reach a critical length and the cell typically dies. Sometimes, however, the cells cease to divide and are subjected to genomic instability, promoting inflammation in the body.
Scientists have known for more than a decade that the length of telomeres in immune system cells is a marker of cell aging. In recent years, they have discovered that shorter telomeres are associated with a broad range of aging-related diseases and are predictive of incidence and poor prognosis of cardiovascular disease and a variety of cancers.
A 2004 study led by Blackburn and UCSF colleague Elissa Epel, PhD, associate professor of psychiatry, suggested that psychological stress may impact the length of telomeres in immune system cells. They reported that the perception of psychological stress in female caregivers of chronically sick children was related to shorter telomeres in lymphocytes, key cells of the immune system. This offered the first evidence that telomere maintenance potentially mediates the well documented detrimental effects of stress on health. (Proceedings of the National Academy of Sciences, Nov. 29, 2004)
In the current research, one study, led by Epel, followed for two years 63 healthy postmenopausal women who were the primary caregivers for a family member with dementia. In an earlier analysis of 36 of these women, pessimism was associated with high levels of a pro-inflammatory protein often associated with aging and disease states, and with short telomeres. In a recent and separate analysis of the full group of women, an increase in perceived stress was related to an increase in the odds of having short telomeres only in the non-exercising women. Among those who exercised, perceived stress was unrelated to telomere length. In the current analysis of the larger group, it was revealed that an increase in perceived stress over the course of one year was associated with a decrease in telomere length during that time.
A second study, led by Aoife O'Donovan, PhD, and Thomas Neylan, MD, UCSF professor of psychiatry at the San Francisco VA Medical Center, examined 43 people ages 20 to 50 with chronic post-traumatic stress disorder. They were compared to 47 age- and sex-matched individuals without PTSD.The results showed a relationship between PTSD and short telomere length. But even more interesting, said Lin, the finding showed that, in these adults, exposure to childhood trauma – at or before age 14 – also was associated with telomere shortening and accounted for the link between PTSD and telomeres.
A third study, led by Eli Puterman, PhD, analyzed data from 251 healthy, non-smoking women ages 50-65 of varying activity levels. The findings showed that non-exercising women with histories of childhood abuse had shorter telomeres than those with no histories of abuse. But, in those women who exercised regularly, there was no link between childhood abuse and telomere length, after controlling for body mass index, income, education and age.
"We saw a relationship between childhood trauma and short telomere length but the relationship seems to go away in people who exercise vigorously at least three times a week," Lin said.
UCSF scientists are reporting several studies showing that psychological stress leads to shorter telomeres – the protective caps on the ends of chromosomes that are a measure of cell age and, thus, health. The findings also suggest that exercise may prevent this damage.
The team focused on three groups: post-menopausal women who were the primary caregivers for a family member with dementia; young to middle-aged adults with post-traumatic stress disorder; and healthy, non-smoking women ages 50 to 65 years.
They examined telomeres in leukocytes, or white blood cells, of the immune system, which defends the body against both infectious agents and cell damage.
"Our findings suggest that traumatic and chronic stressful life events are associated with shortening of telomeres in cells of the immune system, but that physical activity may moderate this impact," said co-author Jue Lin, PhD, associate research biochemist in the laboratory of senior author and Nobel laureate Elizabeth Blackburn, PhD, professor of biochemistry and biophysics at UCSF.
Lin presented the findings in a poster session on Monday, April 4, 2011, at the AACR 102nd Annual Meeting 2011.
Telomeres are tiny units of DNA at the ends of chromosomes that protect and stabilize chromosomes. Every time a cell divides, some telomeres drop off. After a certain number of cell divisions, which varies depending on the cell type, the telomeres reach a critical length and the cell typically dies. Sometimes, however, the cells cease to divide and are subjected to genomic instability, promoting inflammation in the body.
Scientists have known for more than a decade that the length of telomeres in immune system cells is a marker of cell aging. In recent years, they have discovered that shorter telomeres are associated with a broad range of aging-related diseases and are predictive of incidence and poor prognosis of cardiovascular disease and a variety of cancers.
A 2004 study led by Blackburn and UCSF colleague Elissa Epel, PhD, associate professor of psychiatry, suggested that psychological stress may impact the length of telomeres in immune system cells. They reported that the perception of psychological stress in female caregivers of chronically sick children was related to shorter telomeres in lymphocytes, key cells of the immune system. This offered the first evidence that telomere maintenance potentially mediates the well documented detrimental effects of stress on health. (Proceedings of the National Academy of Sciences, Nov. 29, 2004)
In the current research, one study, led by Epel, followed for two years 63 healthy postmenopausal women who were the primary caregivers for a family member with dementia. In an earlier analysis of 36 of these women, pessimism was associated with high levels of a pro-inflammatory protein often associated with aging and disease states, and with short telomeres. In a recent and separate analysis of the full group of women, an increase in perceived stress was related to an increase in the odds of having short telomeres only in the non-exercising women. Among those who exercised, perceived stress was unrelated to telomere length. In the current analysis of the larger group, it was revealed that an increase in perceived stress over the course of one year was associated with a decrease in telomere length during that time.
A second study, led by Aoife O'Donovan, PhD, and Thomas Neylan, MD, UCSF professor of psychiatry at the San Francisco VA Medical Center, examined 43 people ages 20 to 50 with chronic post-traumatic stress disorder. They were compared to 47 age- and sex-matched individuals without PTSD.The results showed a relationship between PTSD and short telomere length. But even more interesting, said Lin, the finding showed that, in these adults, exposure to childhood trauma – at or before age 14 – also was associated with telomere shortening and accounted for the link between PTSD and telomeres.
A third study, led by Eli Puterman, PhD, analyzed data from 251 healthy, non-smoking women ages 50-65 of varying activity levels. The findings showed that non-exercising women with histories of childhood abuse had shorter telomeres than those with no histories of abuse. But, in those women who exercised regularly, there was no link between childhood abuse and telomere length, after controlling for body mass index, income, education and age.
"We saw a relationship between childhood trauma and short telomere length but the relationship seems to go away in people who exercise vigorously at least three times a week," Lin said.
Vitamin D Levels Linked With Health of Blood Vessels
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A lack of vitamin D, even in generally healthy people, is linked with stiffer arteries and an inability of blood vessels to relax, research from the Emory/Georgia Tech Predictive Health Institute has found.
The results add to evidence that lack of vitamin D can lead to impaired vascular health, contributing to high blood pressure and the risk of cardiovascular disease. Study participants who increased their vitamin D levels were able to improve vascular health and lower their blood pressure.
The data was presented by Ibhar Al Mheid, MD, a cardiovascular researcher at Emory University School of Medicine, at the annual American College of Cardiology meeting in New Orleans. Al Mheid is one of five finalists for the ACC's Young Investigators Award competition in physiology, pharmacology and pathology. He is working with Arshed Quyyumi, MD, professor of medicine and director of the Emory Cardiovascular Research Institute.
The 554 participants in the study were Emory or Georgia Tech employees -average age 47 and generally healthy -- who are taking part in the Center for Health Discovery and Well Being, part of the Emory/Georgia Tech Predictive Health Institute.
The average level of 25-hydroxyvitamin D (a stable form of the vitamin reflecting diet as well as production in the skin) in participants' blood was 31.8 nanograms per milliliter. In this group, 14 percent had 25-hydroxyvitamin D levels considered deficient, or less than 20 nanograms per milliliter, and 33 percent had levels considered insufficient, less than 30 nanograms per milliliter.
The researchers monitored the ability of participants' blood vessels to relax by inflating and then removing a blood pressure cuff on their arms. To allow blood to flow back into the arm, blood vessels must relax and enlarge -- a change that can be measured by ultrasound. The researchers also made other measurements of smaller blood vessels and examined the resistance to blood flow imposed by the arteries.
Even after controlling for factors such as age, weight and cholesterol, people with lower vitamin D levels still had stiffer arteries and impaired vascular function, Al Mheid says.
"We found that people with vitamin D deficiency had vascular dysfunction comparable to those with diabetes or hypertension," he says.
Throughout the body, a layer of endothelial cells lines the blood vessels, controlling whether the blood vessels constrict or relax and helping to prevent clots that lead to strokes and heart attacks.
"There is already a lot known about how vitamin D could be acting here," Al Mheid says. "It could be strengthening endothelial cells and the muscles surrounding the blood vessels. It could also be reducing the level of angiotensin, a hormone that drives increased blood pressure, or regulating inflammation."
Most Americans generally get the majority of their vitamin D from exposure to sunlight or from dietary supplements; fortified foods such as milk or cereals are a minor source. A few foods, such as oily fish, naturally contain substantial amounts of vitamin D.
Participants whose vitamin D levels increased over the next six months, either from dietary supplements or ample sun exposure, tended to improve their measures of vascular health and had lower blood pressure. Forty-two study participants with vitamin D insufficiency whose levels later went back to normal had an average drop in blood pressure of 4.6 millimeters mercury.
"This was an observational study, rather than an interventional one, and it was difficult to tease out how the people who restored their vitamin D levels got there," Al Mheid says. "We are hoping to conduct a study where we have participants take a defined regimen of vitamin D."
"With his findings showing the relationship between vitamin D deficiency and vascular dysfunction, Dr. Mheid has helped advance our understanding of the importance of Vitamin D in preventing a common health problem in aging adults," says Kenneth Brigham, MD, medical director of the Emory/Georgia Tech Center for Health Discovery and Well Being. "Additionally, ongoing health studies based on the Center's collection of health information from participants will yield more discovery as the Center continues to develop."
The Emory-Georgia Tech Predictive Health Institute is a national leader in moving the practice of medicine from a reactive, disease-focused system to a proactive health-focused system. The initiative integrates research, scholarship and education in an innovative effort aimed at revolutionizing care of people to define, preserve and prolong the health of individuals and of society.
Key areas of the Initiative include defining and measuring health using optimal biomarkers of health and understand their interrelationships, determining the best interventions to optimize health throughout an individual's or a population's lifetime.
A lack of vitamin D, even in generally healthy people, is linked with stiffer arteries and an inability of blood vessels to relax, research from the Emory/Georgia Tech Predictive Health Institute has found.
The results add to evidence that lack of vitamin D can lead to impaired vascular health, contributing to high blood pressure and the risk of cardiovascular disease. Study participants who increased their vitamin D levels were able to improve vascular health and lower their blood pressure.
The data was presented by Ibhar Al Mheid, MD, a cardiovascular researcher at Emory University School of Medicine, at the annual American College of Cardiology meeting in New Orleans. Al Mheid is one of five finalists for the ACC's Young Investigators Award competition in physiology, pharmacology and pathology. He is working with Arshed Quyyumi, MD, professor of medicine and director of the Emory Cardiovascular Research Institute.
The 554 participants in the study were Emory or Georgia Tech employees -average age 47 and generally healthy -- who are taking part in the Center for Health Discovery and Well Being, part of the Emory/Georgia Tech Predictive Health Institute.
The average level of 25-hydroxyvitamin D (a stable form of the vitamin reflecting diet as well as production in the skin) in participants' blood was 31.8 nanograms per milliliter. In this group, 14 percent had 25-hydroxyvitamin D levels considered deficient, or less than 20 nanograms per milliliter, and 33 percent had levels considered insufficient, less than 30 nanograms per milliliter.
The researchers monitored the ability of participants' blood vessels to relax by inflating and then removing a blood pressure cuff on their arms. To allow blood to flow back into the arm, blood vessels must relax and enlarge -- a change that can be measured by ultrasound. The researchers also made other measurements of smaller blood vessels and examined the resistance to blood flow imposed by the arteries.
Even after controlling for factors such as age, weight and cholesterol, people with lower vitamin D levels still had stiffer arteries and impaired vascular function, Al Mheid says.
"We found that people with vitamin D deficiency had vascular dysfunction comparable to those with diabetes or hypertension," he says.
Throughout the body, a layer of endothelial cells lines the blood vessels, controlling whether the blood vessels constrict or relax and helping to prevent clots that lead to strokes and heart attacks.
"There is already a lot known about how vitamin D could be acting here," Al Mheid says. "It could be strengthening endothelial cells and the muscles surrounding the blood vessels. It could also be reducing the level of angiotensin, a hormone that drives increased blood pressure, or regulating inflammation."
Most Americans generally get the majority of their vitamin D from exposure to sunlight or from dietary supplements; fortified foods such as milk or cereals are a minor source. A few foods, such as oily fish, naturally contain substantial amounts of vitamin D.
Participants whose vitamin D levels increased over the next six months, either from dietary supplements or ample sun exposure, tended to improve their measures of vascular health and had lower blood pressure. Forty-two study participants with vitamin D insufficiency whose levels later went back to normal had an average drop in blood pressure of 4.6 millimeters mercury.
"This was an observational study, rather than an interventional one, and it was difficult to tease out how the people who restored their vitamin D levels got there," Al Mheid says. "We are hoping to conduct a study where we have participants take a defined regimen of vitamin D."
"With his findings showing the relationship between vitamin D deficiency and vascular dysfunction, Dr. Mheid has helped advance our understanding of the importance of Vitamin D in preventing a common health problem in aging adults," says Kenneth Brigham, MD, medical director of the Emory/Georgia Tech Center for Health Discovery and Well Being. "Additionally, ongoing health studies based on the Center's collection of health information from participants will yield more discovery as the Center continues to develop."
The Emory-Georgia Tech Predictive Health Institute is a national leader in moving the practice of medicine from a reactive, disease-focused system to a proactive health-focused system. The initiative integrates research, scholarship and education in an innovative effort aimed at revolutionizing care of people to define, preserve and prolong the health of individuals and of society.
Key areas of the Initiative include defining and measuring health using optimal biomarkers of health and understand their interrelationships, determining the best interventions to optimize health throughout an individual's or a population's lifetime.
Saturday, April 2, 2011
Older and stronger: Progressive resistance training
Ω
We can build muscle, increase strength as we age
Researchers at the University of Michigan say older adults don’t have to accept strength muscle loss as they age
Getting older doesn't mean giving up muscle strength.
Not only can adults fight the battle of strength and muscle loss that comes with age, but the Golden Years can be a time to get stronger, say experts at the University of Michigan Health System.
"Resistance exercise is a great way to increase lean muscle tissue and strength capacity so that people can function more readily in daily life," says Mark Peterson, Ph.D., a research fellow in the U-M Physical Activity and Exercise Intervention Research Laboratory, at the Department of Physical Medicine and Rehabilitation.
Through resistance training adults can improve their ability to stand up out of a chair walk across the floor, climb a flight of stairs -- anything that requires manipulating their own body mass through a full range of motions.
Normally, adults who are sedentary beyond age 50 can expect muscle loss of up to 0.4 pounds a year.
"That only worsens as people age. But even earlier in adulthood - the 30s, 40s and 50s - you can begin to see declines if you do not engage in any strengthening activities," Peterson says.
"Our analyses of current research show that the most important factor in somebody's function is their strength capacity. No matter what age an individual is, they can experience significant strength improvement with progressive resistance exercise even into the eighth and ninth decades of life," he says.
Progressive resistance training means that the amount of weight used, and the frequency and duration of training sessions is altered over time to accommodate an individual's improvements.
A review article by U-M researchers, published in The American Journal of Medicine, shows that after an average of 18-20 weeks of progressive resistance training, an adult can add 2.42 pounds of lean muscle to their body mass and increases their overall strength by 25-30 percent.
Recommendations for those over age 50
Peterson says that anyone over age 50 should strongly consider participating in resistance exercise.
A good way for people to start on a resistance training program, especially for people who are relatively sedentary – and after getting permission from their doctor to do so - is to use their body mass as a load for various exercises.
Exercises you can do using your own body weight include squats, standing up out of a chair, modified push-ups, lying hip bridges, as well as non-traditional exercises that progress through a full range of motion, such as Thai Chi or Pilates and Yoga.
Transition to the gym
After getting accustomed to these activities, older adults can move on to more advanced resistance training in an exercise and fitness facility. A certified trainer or fitness professional that has experience with special populations can help with the transition.
Peterson says you should feel comfortable asking a trainer whether they have experience working with aging adults before you begin any fitness routine.
"Working out at age 20 is not the same as at age 70. A fitness professional who understands those differences is important for your safety. In addition, current recommendations suggest that an older individual participate in strengthening exercise two days per week," Peterson says. "Based on the results of our studies, I would suggest that be thought of as the minimum."
Don't forget to progress
As resistance training progresses and weights and machines are introduced, Peterson recommends incorporating full body exercises and exercises that use more than one joint and muscle group at a time, such as the leg press, chest press, and rows. These are safer and more effective in building muscle mass.
"You should also keep in mind the need for increased resistance and intensity of your training to continue building muscle mass and strength," he says.
A good fitness professional can help plan an appropriate training regimen, and make adjustments based on how you respond as you progress.
"We firmly believe based on this research that progressive resistance training should be encouraged among healthy older adults to help minimize the loss of muscle mass and strength as they age," Peterson says.
Ω
We can build muscle, increase strength as we age
Researchers at the University of Michigan say older adults don’t have to accept strength muscle loss as they age
Getting older doesn't mean giving up muscle strength.
Not only can adults fight the battle of strength and muscle loss that comes with age, but the Golden Years can be a time to get stronger, say experts at the University of Michigan Health System.
"Resistance exercise is a great way to increase lean muscle tissue and strength capacity so that people can function more readily in daily life," says Mark Peterson, Ph.D., a research fellow in the U-M Physical Activity and Exercise Intervention Research Laboratory, at the Department of Physical Medicine and Rehabilitation.
Through resistance training adults can improve their ability to stand up out of a chair walk across the floor, climb a flight of stairs -- anything that requires manipulating their own body mass through a full range of motions.
Normally, adults who are sedentary beyond age 50 can expect muscle loss of up to 0.4 pounds a year.
"That only worsens as people age. But even earlier in adulthood - the 30s, 40s and 50s - you can begin to see declines if you do not engage in any strengthening activities," Peterson says.
"Our analyses of current research show that the most important factor in somebody's function is their strength capacity. No matter what age an individual is, they can experience significant strength improvement with progressive resistance exercise even into the eighth and ninth decades of life," he says.
Progressive resistance training means that the amount of weight used, and the frequency and duration of training sessions is altered over time to accommodate an individual's improvements.
A review article by U-M researchers, published in The American Journal of Medicine, shows that after an average of 18-20 weeks of progressive resistance training, an adult can add 2.42 pounds of lean muscle to their body mass and increases their overall strength by 25-30 percent.
Recommendations for those over age 50
Peterson says that anyone over age 50 should strongly consider participating in resistance exercise.
A good way for people to start on a resistance training program, especially for people who are relatively sedentary – and after getting permission from their doctor to do so - is to use their body mass as a load for various exercises.
Exercises you can do using your own body weight include squats, standing up out of a chair, modified push-ups, lying hip bridges, as well as non-traditional exercises that progress through a full range of motion, such as Thai Chi or Pilates and Yoga.
Transition to the gym
After getting accustomed to these activities, older adults can move on to more advanced resistance training in an exercise and fitness facility. A certified trainer or fitness professional that has experience with special populations can help with the transition.
Peterson says you should feel comfortable asking a trainer whether they have experience working with aging adults before you begin any fitness routine.
"Working out at age 20 is not the same as at age 70. A fitness professional who understands those differences is important for your safety. In addition, current recommendations suggest that an older individual participate in strengthening exercise two days per week," Peterson says. "Based on the results of our studies, I would suggest that be thought of as the minimum."
Don't forget to progress
As resistance training progresses and weights and machines are introduced, Peterson recommends incorporating full body exercises and exercises that use more than one joint and muscle group at a time, such as the leg press, chest press, and rows. These are safer and more effective in building muscle mass.
"You should also keep in mind the need for increased resistance and intensity of your training to continue building muscle mass and strength," he says.
A good fitness professional can help plan an appropriate training regimen, and make adjustments based on how you respond as you progress.
"We firmly believe based on this research that progressive resistance training should be encouraged among healthy older adults to help minimize the loss of muscle mass and strength as they age," Peterson says.
Ω
Got a craving for fast food? Skip the coffee
Ω
Eating a fatty fast food meal is never good for you, but washing that meal down with a coffee is even worse, according to a new University of Guelph study.
Researcher Marie-Soleil Beaudoin has discovered not only that a healthy person's blood sugar levels spike after eating a high-fat meal, but that the spike doubles after having both a fatty meal and caffeinated coffee – jumping to levels similar to those of people at risk for diabetes.
"The results tell us that saturated fat interferes with the body's ability to clear sugars from the blood and, when combined with caffeinated coffee, the impact can be even worse," said Beaudoin, a PhD student who conducted the study with U of G professors Lindsay Robinson and Terry Graham. "Having sugar remain in our blood for long periods is unhealthy because it can take a toll on our body's organs."
Published today in the Journal of Nutrition¸ the study is the first to examine the effects of saturated fat and caffeinated coffee on blood sugar levels using a novel fat cocktail which contains only lipids. This specially designed beverage allows researchers to accurately mimic what happens to the body when we ingest fat.
For the study, healthy men drank about one gram of the fat beverage for every kilogram of body weight for their first meal. Six hours later, they were given a second meal consisting of a sugar drink.
Typically when we ingest sugar, the body produces insulin, which takes the sugar out of the blood and distributes it to our muscles, said Beaudoin.
But the researchers found that the fatty meal affected the body's ability to clear the sugar out of the blood. The subjects' blood sugar levels were 32 per cent higher than they were when the men had not ingested the fat cocktail.
The researchers also tested the impact of caffeinated coffee combined with the fatty meal. For this test, participants received the equivalent of two cups of caffeinated coffee five hours after ingesting the fat beverage. An hour later, they were then given the sugar drink.
The results showed blood sugar levels increased by 65 per cent compared to what they were when participants had not ingested the fat and caffeinated coffee.
"This shows that the effects of a high-fat meal can last for hours," said Beaudoin. "What you eat for lunch can impact how your body responds to food later in the day."
Besides testing the participant's blood sugar levels, the researchers looked at gastro-intestinal effects by measuring incretin hormones released by the gut after ingesting the fat. These hormones signal the pancreas to release insulin to help clear the blood of sugar. The researchers discovered these hormones' responses to carbohydrates are blunted after ingesting the fat beverage.
"Ultimately we have found that fat and caffeinated coffee are impairing the communication between the gut and the pancreas, which could be playing a role in why participants couldn't clear the sugar from their blood as easily," said Beaudoin.
The results of the study are particularly important for people at risk for metabolic diseases and Type 2 diabetes, she adds.
"We have known for many years that people with or at risk of Type 2 diabetes should limit their caffeine intake. Drinking decaffeinated coffee instead of caffeinated is one way to improve one's glucose tolerance. Limiting the intake of saturated fatty acids found in red meat, processed foods and fast food meals is also beneficial. This study has shown that the affects of these foods can be severe and long lasting."
Eating a fatty fast food meal is never good for you, but washing that meal down with a coffee is even worse, according to a new University of Guelph study.
Researcher Marie-Soleil Beaudoin has discovered not only that a healthy person's blood sugar levels spike after eating a high-fat meal, but that the spike doubles after having both a fatty meal and caffeinated coffee – jumping to levels similar to those of people at risk for diabetes.
"The results tell us that saturated fat interferes with the body's ability to clear sugars from the blood and, when combined with caffeinated coffee, the impact can be even worse," said Beaudoin, a PhD student who conducted the study with U of G professors Lindsay Robinson and Terry Graham. "Having sugar remain in our blood for long periods is unhealthy because it can take a toll on our body's organs."
Published today in the Journal of Nutrition¸ the study is the first to examine the effects of saturated fat and caffeinated coffee on blood sugar levels using a novel fat cocktail which contains only lipids. This specially designed beverage allows researchers to accurately mimic what happens to the body when we ingest fat.
For the study, healthy men drank about one gram of the fat beverage for every kilogram of body weight for their first meal. Six hours later, they were given a second meal consisting of a sugar drink.
Typically when we ingest sugar, the body produces insulin, which takes the sugar out of the blood and distributes it to our muscles, said Beaudoin.
But the researchers found that the fatty meal affected the body's ability to clear the sugar out of the blood. The subjects' blood sugar levels were 32 per cent higher than they were when the men had not ingested the fat cocktail.
The researchers also tested the impact of caffeinated coffee combined with the fatty meal. For this test, participants received the equivalent of two cups of caffeinated coffee five hours after ingesting the fat beverage. An hour later, they were then given the sugar drink.
The results showed blood sugar levels increased by 65 per cent compared to what they were when participants had not ingested the fat and caffeinated coffee.
"This shows that the effects of a high-fat meal can last for hours," said Beaudoin. "What you eat for lunch can impact how your body responds to food later in the day."
Besides testing the participant's blood sugar levels, the researchers looked at gastro-intestinal effects by measuring incretin hormones released by the gut after ingesting the fat. These hormones signal the pancreas to release insulin to help clear the blood of sugar. The researchers discovered these hormones' responses to carbohydrates are blunted after ingesting the fat beverage.
"Ultimately we have found that fat and caffeinated coffee are impairing the communication between the gut and the pancreas, which could be playing a role in why participants couldn't clear the sugar from their blood as easily," said Beaudoin.
The results of the study are particularly important for people at risk for metabolic diseases and Type 2 diabetes, she adds.
"We have known for many years that people with or at risk of Type 2 diabetes should limit their caffeine intake. Drinking decaffeinated coffee instead of caffeinated is one way to improve one's glucose tolerance. Limiting the intake of saturated fatty acids found in red meat, processed foods and fast food meals is also beneficial. This study has shown that the affects of these foods can be severe and long lasting."
Maple syrup's health benefits
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Pure maple syrup may pack similar health benefits to those found in berries, tea, red wine and flax seed
There's good news about pure maple syrup from the University of Rhode Island (URI). Researchers there have now identified 54 compounds in maple syrup from Canada, double the amount previously reported, and many with antioxidant activity and potential health benefits. In laboratory studies, they acted as anti-cancer and anti-inflammatory agents. Initial studies also suggest that maple compounds may inhibit enzymes relevant in Type 2 diabetes management.
These new findings were presented on March 30th at the annual meeting of the American Chemical Society in Anaheim, CA, during a day-long session exclusively examining the bioactive compounds found in natural sweeteners. The session was organized and chaired by Dr. Navindra Seeram, assistant pharmacy professor at URI and a lead scientist on the maple syrup research team.
According to the URI research team, maple syrup contains a cocktail of polyphenol compounds, several with antioxidant properties and many with well-documented health benefits. "We found a wide variety of polyphenols in maple syrup," said Seeram. "It is a one-stop shop for these beneficial compounds, several of which are also found in berries, tea, red wine and flaxseed, just to name a few," Seeram continued. "Not all sweeteners are created equal. When choosing a sweetener, pure maple syrup may be a better choice because of the range of antioxidant compounds not found in other sweeteners."
Maple syrup may prove to be relevant in Type 2 diabetes management, although the findings must be verified in clinical trials. "We discovered that the polyphenols in maple syrup inhibit enzymes that are involved in the conversion of carbohydrate to sugar," said Seeram. "In fact, in preliminary studies maple syrup had a greater enzyme-inhibiting effect compared to several other healthy plant foods such as berries, when tested on a dry-weight basis. By 2050, one in three people will be afflicted with Type 2 diabetes and more and more people are looking for healthier diets, so finding a potential anti-diabetic compound in maple syrup is interesting for the scientific community and the consumer," said Seeram.
Five of the 54 antioxidants in maple syrup were identified for the first time in nature, and are unique to the natural sweetener. Among the five new compounds never before identified, one polyphenol is of particular interest. Given the common name of Quebecol, in honor of the province of Quebec, this compound is created during the process of boiling down maple sap into maple syrup. "We don't know yet whether the new compounds contribute to the healthy profile of maple syrup, but we do know that the sheer quantity and variety of identified compounds with documented health benefits qualifies maple syrup as a champion food," commented Seeram, whose findings have recently been published in the Journal of Functional Foods. Dr. Seeram's work at URI is supported by a grant funded by The Federation of Quebec Maple Syrup Producers, in conjunction with the Conseil pour le développement de l'agriculture du Québec (CDAQ) and Agriculture and Agri-Food Canada (AAFC) on behalf of the Canadian Maple Syrup Industry.
Attendees at the American Chemical Society's annual meeting also heard promising results from other Canadian researchers who are studying the health benefits of maple syrup. "Part of our New Generation of Maple 2020 strategy is to work with talented scientists to discover and share more knowledge about maple syrup. We are excited that this line of research receives interest from all over the world," says Serge Beaulieu, President of the Federation and member of the Canadian Maple Industry Advisory Committee. Geneviève Béland, Marketing Director for the Federation, adds "Maple is the most important food derived from the pure sap of trees, and given its amazing potential for human health and great nutritional value, it is a natural choice for a healthy lifestyle." The Federation's members produce about 80 percent of the worldwide supply of the natural sweetener.
Pure maple syrup may pack similar health benefits to those found in berries, tea, red wine and flax seed
There's good news about pure maple syrup from the University of Rhode Island (URI). Researchers there have now identified 54 compounds in maple syrup from Canada, double the amount previously reported, and many with antioxidant activity and potential health benefits. In laboratory studies, they acted as anti-cancer and anti-inflammatory agents. Initial studies also suggest that maple compounds may inhibit enzymes relevant in Type 2 diabetes management.
These new findings were presented on March 30th at the annual meeting of the American Chemical Society in Anaheim, CA, during a day-long session exclusively examining the bioactive compounds found in natural sweeteners. The session was organized and chaired by Dr. Navindra Seeram, assistant pharmacy professor at URI and a lead scientist on the maple syrup research team.
According to the URI research team, maple syrup contains a cocktail of polyphenol compounds, several with antioxidant properties and many with well-documented health benefits. "We found a wide variety of polyphenols in maple syrup," said Seeram. "It is a one-stop shop for these beneficial compounds, several of which are also found in berries, tea, red wine and flaxseed, just to name a few," Seeram continued. "Not all sweeteners are created equal. When choosing a sweetener, pure maple syrup may be a better choice because of the range of antioxidant compounds not found in other sweeteners."
Maple syrup may prove to be relevant in Type 2 diabetes management, although the findings must be verified in clinical trials. "We discovered that the polyphenols in maple syrup inhibit enzymes that are involved in the conversion of carbohydrate to sugar," said Seeram. "In fact, in preliminary studies maple syrup had a greater enzyme-inhibiting effect compared to several other healthy plant foods such as berries, when tested on a dry-weight basis. By 2050, one in three people will be afflicted with Type 2 diabetes and more and more people are looking for healthier diets, so finding a potential anti-diabetic compound in maple syrup is interesting for the scientific community and the consumer," said Seeram.
Five of the 54 antioxidants in maple syrup were identified for the first time in nature, and are unique to the natural sweetener. Among the five new compounds never before identified, one polyphenol is of particular interest. Given the common name of Quebecol, in honor of the province of Quebec, this compound is created during the process of boiling down maple sap into maple syrup. "We don't know yet whether the new compounds contribute to the healthy profile of maple syrup, but we do know that the sheer quantity and variety of identified compounds with documented health benefits qualifies maple syrup as a champion food," commented Seeram, whose findings have recently been published in the Journal of Functional Foods. Dr. Seeram's work at URI is supported by a grant funded by The Federation of Quebec Maple Syrup Producers, in conjunction with the Conseil pour le développement de l'agriculture du Québec (CDAQ) and Agriculture and Agri-Food Canada (AAFC) on behalf of the Canadian Maple Syrup Industry.
Attendees at the American Chemical Society's annual meeting also heard promising results from other Canadian researchers who are studying the health benefits of maple syrup. "Part of our New Generation of Maple 2020 strategy is to work with talented scientists to discover and share more knowledge about maple syrup. We are excited that this line of research receives interest from all over the world," says Serge Beaulieu, President of the Federation and member of the Canadian Maple Industry Advisory Committee. Geneviève Béland, Marketing Director for the Federation, adds "Maple is the most important food derived from the pure sap of trees, and given its amazing potential for human health and great nutritional value, it is a natural choice for a healthy lifestyle." The Federation's members produce about 80 percent of the worldwide supply of the natural sweetener.
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