Health Benefits of Dairy Foods: Diabetes and Metabolic Health

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Diabetes

High-fat dairy products linked to reduced type 2 diabetes risk

A new study indicates that  high-fat dairy products specifically that are associated with reduced risk. The findings, which have been published in the American Journal of Clinical Nutrition, are in line with previous studies of eating habits that indicated a link between high consumption of dairy products and a reduced risk of type 2 diabetes, But focuses on the fat content, which previous studies did not.

"Those who ate the most high-fat dairy products had a 23 per cent lower risk of developing type 2 diabetes than those who ate the least. High meat consumption was linked to an increased risk of type 2 diabetes regardless of the fat content of the meat", said Ulrika Ericson, who conducted the study.

The researchers studied the eating habits of 27 000 individuals aged 45 to 74. The participants took part in the Malmö Diet and Cancer study in the early 1990s, in which they provided details of their eating habits. Twenty years on, over ten per cent - 2 860 people - had developed type 2 diabetes.

The aim of the study has been to clarify the significance of fat in food for the risk of developing type 2 diabetes. Instead of focusing on the total intake of saturated fat, the researchers looked at different sources of saturated fat.

Both meat and dairy products contain saturated fat, but certain saturated fatty acids are particularly common in dairy products. This difference could be one of the reasons why most studies show that those who eat meat are at higher risk of type 2 diabetes, whereas those who eat a lot of dairy products appear to have a lower risk.

"When we investigated the consumption of saturated fatty acids that are slightly more common in dairy products than in meat, we observed a link with a reduced risk of type 2 diabetes. However, we have not ruled out the possibility that other components of dairy products such as yoghurt and cheese may have contributed to our results. We have taken into account many dietary and lifestyle factors in our analysis, such as fermentation, calcium, vitamin D and physical activity. However, there may be other factors that we have not been able to measure that are shared by those who eat large quantities of high-fat dairy products. Moreover, different food components can interact with each other. For example, in one study, saturated fat in cheese appeared to have less of a cholesterol-raising effect than saturated fat in butter.

"Our results suggest that we should not focus solely on fat, but rather consider what foods we eat. Many foodstuffs contain different components that are harmful or beneficial to health, and it is the overall balance that is important."

Dairy is good for metabolic health

Dairy is considered part of a healthy diet and dietary guidelines recommend the daily consumption of 2-4 portions of milk-based products such as milk, yogurt, cheese, cream and butter.  

It’s well known that dairy products contain calcium and minerals good for bones, but new research has shown that dairy consumption may also have beneficial effects on metabolic health and can reduce risk of metabolic diseases such as obesity and type 2 diabetes. 

Curious about these impacts, researchers from CHU de Québec Research Center and  Laval University studied the dairy-eating habits of healthy French-Canadians’ and monitored how dairy consumption may have an effect on their overall metabolic health.  They published their findings today in the journal Applied Physiology, Nutrition, and Metabolism. 

The aim of this study was to determine associations between dairy intake and specific metabolic risk factors, including anthropometric status, plasma glucose, plasma lipid profile, inflammatory markers and blood pressure, in a healthy population.

A total of 254 participants from the greater Quebec City metropolitan area were recruited; 233 participants (105 men and 128 women) met all the eligibility criteria for the study ‒ meaning subjects had healthy metabolic profiles.

The study showed that the average individual consumed 2.5 ± 1.4 portions of dairy per day. However, nearly 45% of the population in this study did not meet Canada’s Food Guide recommendations of at least 2 portions of dairy products a day. These findings are supported by recent Canadian surveys that highlighted an under consumption of dairy products by Canadians.

Data suggest that trans-palmitoleic acid found in plasma may be potentially used as a biomarker to evaluate dairy consumption. Trans-palmitoleic acid, is naturally present in milk, cheese, yogurt, butter, and meat fat but cannot be synthetized by the body. This fatty acid has been recently shown to have health-promoting effects. In this study, that trans-palmitoleic acid level was related to lower blood pressure in men and women, and to lower body weight in men. 

Dairy intake is associated with lower blood glucose and blood pressure in the population studied, though no causal relationships can be made due to the cross-sectional design.  This study adds to a growing body of literature demonstrating a lack of detrimental health effects with higher dairy intake.

Dr. Iwona Rudkowska, a research scientist at the Endocrinology and Nephrology Department, at the CHU de Québec Research Center and assistant professor at Laval University , says   “additional well-designed intervention studies are needed to ascertain the effects of increased dairy consumption on metabolic health in healthy and in metabolically deteriorated populations.” 

Mushrooms boost immunity

Could a mushroom a day help keep the doctor away?

A new University of Florida study shows increased immunity in people who ate a cooked shiitake mushroom every day for four weeks.

Of the thousands of mushroom species globally, about 20 are used for culinary purposes. Shiitake mushrooms are native to Asia and are cultivated for their culinary and medicinal value.

In a 2011 study led by UF Food Science and Human Nutrition Professor Sue Percival, 52 healthy adults, age 21 to 41, came to the Gainesville campus, where researchers gave them a four-week supply of dry shiitake mushrooms. Participants took the mushrooms home, cleaned and cooked them. Then they ate one, 4-ounce serving of mushrooms each day during the experiment.

Through blood tests before and after the experiment, researchers saw better-functioning gamma delta T-cells and reductions in inflammatory proteins.

"If you eat a shiitake mushroom every day, you could see changes in their immune system that are beneficial," said Percival, an Institute of Food and Agricultural Sciences faculty member. "We're enhancing the immune system, but we're also reducing the inflammation that the immune system produces."

To be eligible for the study, participants could not be vegans or vegetarians. They also could not drink tea, take antioxidant supplements or probiotics before the study. They also could not consume more than 14 glasses of alcoholic beverages per week or eat more than seven servings of fruits and vegetables per day during the experiment.

Percival explained the dietary restrictions as follows: Fiber, tea and probiotics help the body's immune system, so researchers didn't want to start with people who already had a strong immune system. Additionally, that much alcohol could suppress immunity, she said.

The study was published online April 11 in the Journal of the American College of Nutrition.

Sugar-sweetened beverages relieve stress, creating potential dependency

-Drinking sugar-sweetened beverages can suppress the hormone cortisol and stress responses in the brain, but diet beverages sweetened with aspartame do not have the same effect, according to a new study published in the Endocrine Society's Journal of Clinical Endocrinology & Metabolism.

"This is the first evidence that high sugar - but not aspartame - consumption may relieve stress in humans," said one of the study's authors, Kevin D. Laugero, PhD, of the University of California, Davis, and the U.S. Department of Agriculture's Agricultural Research Service. "The concern is psychological or emotional stress could trigger the habitual overconsumption of sugar and amplify sugar's detrimental health effects, including obesity."

About 35 percent of adults and nearly 17 percent of children nationwide are obese, according to the Society's Endocrine Facts & Figures report. Sugary drinks such as soda and juice have been linked to this problem. Half of the U.S. population consumes sugar-sweetened drinks on any given day, according to the U.S. Centers for Disease Control and Prevention.

The parallel-arm, double-masked diet intervention study examined the effects of consuming sugar- and aspartame-sweetened beverages on a group of 19 women between the ages of 18 and 40. The researchers assigned eight women to consume aspartame-sweetened beverages, and 11 to drink sugar-sweetened beverages. For a 12-day period, the women drank one of the assigned beverages at breakfast, lunch and dinner. The participants were instructed not to consumer other sugar-sweetened drinks, including fruit juice.

For 3.5 days prior to and after the study, the women consumed a standardized low-sugar diet and stayed at the UC Davis Clinical and Translational Science Center's Clinical Research Center.

Before and after the 12-day experimental period, the women underwent functional MRI screenings after performing math tests to gauge the brain's stress response. The participants also provided saliva samples to measure levels of cortisol - a hormone made by the adrenal glands that is essential for the body's response to stress.

The researchers found women who drank sugar-sweetened beverages during the study had a diminished cortisol response to the math test, compared to women who were assigned to consume aspartame-sweetened beverages. In addition, the women who consumed sugar-sweetened beverages exhibited more activity in the hippocampus - a part of the brain that is involved in memory and is sensitive to stress - than the women who drank aspartame-sweetened beverages.

The hippocampus typically is less active when the body is under stress. When the study participants drank sugar-sweetened beverages, this response was inhibited. The findings offer new clues that help explain how sugar positively reinforces the temptation to eat comfort food when a person is stressed, Laugero said.

"The results suggest differences in dietary habits may explain why some people underreact to stressful situations and others overreact," he said. "Although it may be tempting to suppress feelings of stress, a normal reaction to stress is important to good health. Research has linked over- and under-reactivity in neural and endocrine stress systems to poor mental and physical health."

Housework keeps older adults more physically and emotionally fit,

Older adults who keep a clean and orderly home--because of the exercise it takes to get the job done--tend to feel emotionally and physically better after tackling house chores, according to new findings by a Case Western Reserve University school of nursing researcher.

"House cleaning kept them up and moving," said Kathy D. Wright, PhD, RN, CNS, a postdoctoral KL2 Scholar at the university's Frances Payne Bolton School of Nursing. "A clean environment is therapeutic."

Wright and a research team set out to test a theory called House's Conceptual Framework for Understanding Social Inequalities in Health and Aging. It's considered a blueprint for understanding how factors such as income, education, environment and health behaviors, like smoking and exercise, influence an older person's health.

The study's 337 participants, from 65 to 94 years old, had to have at least one chronic illness, be enrolled in both Medicare and Medicaid, have physical restrictions that prevented them from doing at least one basic daily task, such as bathing and dressing, and be unable to manage such responsibilities as taking medicines, handling finances or accessing transportation. All lived in Ohio's Summit and Portage counties.

They discussed their backgrounds and physical and emotional well-being in interviews. The researchers then used the University of Utah's Digit Lab, where Wright earned her doctorate degree while working for the Summa Health System, to link geographic and socioeconomic information on the neighborhoods with health data.

Wright said she was surprised to learn that housework and maintaining their property affected the participants' physical and mental well-being more than such factors as neighborhood or income.

"What I found was that neighborhood poverty did not directly affect mental or physical health," she said.

The study provided evidence that Wright had observed in her visits: people living in a chaotic environment seemed less satisfied than those in a place that was neat and tidy.

Wright hopes the study shows how important it is for sedentary older adults with disabilities and chronic illnesses to continue physical activities, such as doing reaching exercises while sitting, arm curls and standing up and sitting down in a chair.

Wright and her team's findings were reported in the recent Geriatric Nursing article, "Factors that Influence physical function and emotional well-being among Medicare-Medicaid enrollees."

Genetics overlap found between Alzheimer's disease and cardiovascular risk factors

An international team of scientists, led by researchers at University of California, San Diego School of Medicine, have found genetic overlap between Alzheimer's disease (AD) and two significant cardiovascular disease risk factors: high levels of inflammatory C-reactive protein (CRP) and plasma lipids or fats. The findings, based upon genome-wide association studies involving hundreds of thousands of individuals, suggest the two cardiovascular phenotypes play a role in AD risk - and perhaps offer a new avenue for potentially delaying disease progression.

The findings are published in current online issue of Circulation.

"For many years we have known that high levels of cholesterol and high levels of inflammation are associated with increased risks for Alzheimer's disease," said study co-author Paul M Ridker, MD, MPH, the Eugene Braunwald Professor of Medicine at Harvard Medical School and director of the Center for Cardiovascular Disease Prevention at Brigham and Women's Hospital. "The current work finds that specific genetic signals explain a part of these relationships. We now need to characterize the function of these genetic signals and see whether they can help us to design better trials evaluating inflammation inhibition as a possible method for Alzheimer's treatment."

The researchers used summary statistics from genome-wide association studies of more than 200,000 individuals, looking for overlap in single nucleotide polymorphisms (SNPs) associated with clinically diagnosed AD and CRP and the three components of total cholesterol: high-density lipoprotein (HDL), low-density lipoprotein (LDL) and triglycerides (TG). SNPs are fragments of DNA sequence that commonly vary among individuals within a population.

They found up to a 50-fold enrichment of AD SNPs for different levels of association with CRP, LDL, HDL and TG, which then lead to identification of 55 loci - specific locations on a gene, DNA sequence or chromosome - linked to increased AD risk. The researchers next conducted a meta-analysis of these 55 variants across four independent AD study cohorts, encompassing almost 145,000 persons with AD and healthy controls, revealing two genome-wide significant variants on chromosomes 4 and 10. The two identified genes - HS3ST1 and ECHDC3 - were not previously associated with AD risk.

"Our findings indicate that a subset of genes involved with elevated plasma lipid levels and inflammation may also increase the risk for developing AD. Elevated levels of plasma lipids and inflammation can be modified with treatment, which means it could be possible to identify and therapeutically target individuals at increased risk for developing cardiovascular disease who are also at risk for developing Alzheimer's disease," said Rahul S. Desikan, MD, PhD, research fellow and radiology resident at the UC San Diego School of Medicine and the study's first author.

If so, the research may have significant ramifications. Late-onset AD is the most common form of dementia, affecting an estimated 30 million persons worldwide - a number that is expected to quadruple over the next 40 years. The societal costs, from medical to lost productivity, are staggering. The 2010 World Alzheimer Report estimated total annual costs at $606 billion.

"Currently, there are no disease modifying therapies and much attention has been focused upon prevention and early diagnosis," said Ole A. Andreassen, MD, PhD, a senior co-author and professor of biological psychiatry at the University of Oslo in Norway. "Delaying dementia onset by even just two years could potentially lower the worldwide prevalence of AD by more than 22 million cases over the next four decades, resulting in significant societal savings."

Senior author Anders M. Dale, PhD, professor of neurosciences and radiology and director of the Center for Translational Imaging and Precision Medicine at UC San Diego, said further research will be needed: "Careful and considerable effort will be required to further characterize the novel candidate genes detected in this study and to detect the functional variants responsible for the association of these loci with Alzheimer's risk. It will also be important to understand whether these genes, in combination with other known markers such as brain imaging, cerebrospinal fluid measurements and APOE E4 status, can improve the prediction of disease risk in AD."

Half of older adults in US now taking aspirin

A national survey suggests that slightly more than half of the older adults in the United States are now taking a daily dose of aspirin, even though its use is not recommended by the Food and Drug Administration for most people who have not yet had a heart attack or stroke.

The analysis was published today in the American Journal of Preventive Medicine. It observed that aspirin use is continuing to surge, especially among adults who are using it for "primary prevention," meaning in order to prevent an initial cardiovascular event, and in some cases to prevent cancer.

In this survey of more than 2,500 respondents aged 45-75, 52 percent reported current aspirin use, and another 21 percent had used it at some point in the past. The average age of respondents in the survey was 60. A different report found that aspirin use increased 57 percent between 2005 and 2010.

Aspirin is a blood thinner and can cause bleeding events, which is a primary reason some medical experts recommend caution in its use, even at the "baby aspirin" dose of 81 milligrams often used for disease prevention. The FDA has determined that in primary use to prevent a first heart attack or stroke, for every such event that's prevented, there's approximately one major bleeding event that's caused, such as gastrointestinal bleeding.

Largely on that basis, they have concluded physicians should routinely recommend its use only to patients that have already had a heart attack or stroke. But this study found that 81 percent of older adults who are now using aspirin have not had a heart attack or stroke, and are taking it for primary prevention.

"The use of aspirin is still a very contentious issue among medical experts," said Craig Williams, a pharmacotherapy specialist with the College of Pharmacy at Oregon State University, and lead author of the new report.

"There's no doubt that aspirin use can have value for people who have experienced a first heart attack, stroke or angina," said Williams, a professor in the Oregon State University/Oregon Health & Science University College of Pharmacy. "The data to support that is very strong. The support of its use in primary prevention is more of a mixed bag.

"But this survey clearly shows that more and more people who have not experienced those events and are not technically considered at high risk by the FDA are also deciding to use aspirin, usually in consultation with their doctors."

Aside from cardiovascular events, some studies have suggested a role for aspirin in preventing cancer, Williams said, especially colon cancer. That has further increased interest in its use, he said.

While the FDA takes a more cautious stance, Williams said, some other professional organizations, such as the U.S. Preventative Services Task Force, says aspirin use may be appropriate for primary prevention in people with serious risk factors for cardiovascular disease, such as high blood pressure, high cholesterol, smoking or diabetes. Objective criteria for aspirin use in those patients are based on the number of the risk factors, the age and gender of the patient.

Surveys such as this are needed to help determine how people are managing their own health, Williams said, since aspirin is an over-the-counter medication and its use cannot be determined solely by medical records. And the findings suggest that tens of millions of Americans have reviewed the issues involved, often discussed it with their doctors, say they know what they are doing - and decided to use aspirin.

Among the findings of the report:

• Several markers of healthy lifestyle choices were also associated with aspirin use.
• The strongest predictor of regular aspirin use was a patient having discussed aspirin therapy with a health care provider.
• About 35 percent of people who don't objectively have risk factors that might merit aspirin therapy still use it.
• About 20 percent of people who have already had a heart attack or stroke, and should be on aspirin therapy, do not use it.
• A majority of both current and previous aspirin users rated themselves as being somewhat or very knowledgeable about it.
• Among aspirin users, the reasons cited for its use by respondents was for heart attack prevention, 84 percent; stroke prevention, 66 percent; cancer prevention, 18 percent; and prevention of Alzheimer's disease, 11 percent.
• Significant predictors of aspirin use included people who were physically active, ate healthy foods, had achieved a healthy weight, managed their stress, tried to quit smoking, and/or had undergone health screenings.

Eight nutrients to protect the aging brain

Brain health is the second most important component in maintaining a healthy lifestyle according to a 2014 AARP study. As people age they can experience a range of cognitive issues from decreased critical thinking to dementia and Alzheimer's disease. In the March.2015 issue of Food Technology published by the Institute of Food Technologists (IFT), contributing editor Linda Milo Ohr writes about eight nutrients that may help keep your brain in good shape.

1. Cocoa Flavanols: Cocoa flavanols have been linked to improved circulation and heart health, and preliminary research shows a possible connection to memory improvement as well. A study showed cocoa flavanols may improve the function of a specific part of the brain called the dentate gyrus, which is associated with age-related memory (Brickman, 2014).

2. Omega-3 Fatty Acids: Omega-3 fatty acids have long been shown to contribute to good heart health are now playing a role in cognitive health as well. A study on mice found that omega-3 polyunsaturated fatty acid supplementation appeared to result in better object recognition memory, spatial and localizatory memory (memories that can be consciously recalled such as facts and knowledge), and adverse response retention (Cutuli, 2014). Foods rich in omega-3s include salmon, flaxseed oil, and chia seeds.

3. Phosphatidylserine and Phosphatidic Acid: Two pilot studies showed that a combination of phosphatidylserine and phosphatidic acid can help benefit memory, mood, and cognitive function in the elderly (Lonza, 2014).

4. Walnuts: A diet supplemented with walnuts may have a beneficial effect in reducing the risk, delaying the onset, or slowing the progression of Alzheimer's disease in mice (Muthaiyah, 2014).

5. Citicoline: Citicoline is a natural substance found in the body's cells and helps in the development of brain tissue, which helps regulate memory and cognitive function, enhances communication between neurons, and protects neural structures from free radical damage. Clinical trials have shown citicoline supplements may help maintain normal cognitive function with aging and protect the brain from free radical damage. (Kyowa Hakko USA).

6. Choline: Choline, which is associated with liver health and women's health, also helps with the communication systems for cells within the brain and the rest of the body. Choline may also support the brain during aging and help prevent changes in brain chemistry that result in cognitive decline and failure. A major source of choline in the diet are eggs.

7. Magnesium: Magnesium supplements are often recommended for those who experienced serious concussions. Magnesium-rich foods include avocado, soy beans, bananas and dark chocolate.

8. Blueberries: Blueberries are known to have antioxidant and anti-inflammatory activity because they boast a high concentration of anthocyanins, a flavonoid that enhances the health-promoting quality of foods. Moderate blueberry consumption could offer neurocognitive benefits such as increased neural signaling in the brain centers.