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Mediterranean Diet Linked with Cognitive Benefits, Less Conversion to Alzheimer’s

Research continues to tout the brain benefits of a delicious and nutritious Mediterranean diet. In a review article, Australian researchers analyzed more than a dozen longitudinal and prospective studies (where participants are observed over a long period of time) to determine the link between eating patterns and cognitive health. In the 18 studies, encompassing nearly 60,000 adults total, the scientists found that closely following a Mediterranean diet was associated with “slower rates of cognitive decline, reduced conversion to Alzheimer’s disease, and improvements in cognitive function.” More specifically, the Mediterranean diet was linked with better memory, executive function (which controls behavior, planning, and reasoning), and visual constructs.
Frontiers in Nutrition. 2016 Jul 22;3:22. doi: 10.3389/fnut.2016.00022. [Epub] (Hardman RJ et al.)

Full Fat Mediterranean Diet Linked with Good Health

A healthy diet need not restrict fat or flavor, at least in the case of the delicious and nutritious Mediterranean diet. Researchers at the Department of Veterans Affairs in the U.S. analyzed data from 56 studies (of at least 100 people in each study) to get a big picture view of the Mediterranean diet. The studies were all controlled trials (one of the strongest types of nutrition studies) and were included so long as the participants followed at least 2 of the 7 characteristics of a Mediterranean diet (such as lots of fruits and vegetables, or a preference for olive oil and other unsaturated fats). The scientists found that a Mediterranean diet (with no restriction on fat) may help prevent heart disease, breast cancer, and type 2 diabetes, but they did not find a significant reduction in mortality.
Annals of Internal Medicine. 2016 Jul 19. (Bloomfield HE et al.) [Epub ahead of print]

Fat in Plant Oils, Fatty Fish Better for Blood Sugar Regulation

Researchers from around the globe analyzed findings from 102 randomized clinical trials, encompassing 4,660 participants, to see how different types of fat (saturated, unsaturated, and polyunsaturated) and carbohydrates affect diabetes markers (including blood sugar, insulin production, and insulin sensitivity).  Polyunsaturated fats are found in fatty fish (salmon, trout, mackerel) and plant oils (soybean, sunflower, corn oil), while monounsaturated fats are found in olive and canola oil, and saturated fats are found in red meat and dairy products. The authors found that “substituting carbohydrate and saturated fat with a diet rich in unsaturated fat, particularly polyunsaturated fat, was beneficial for the regulation of blood sugar.” However, the authors did not test the effect of different types of carbohydrate sources (such as differentiating between whole grains, refined grains, or sugars).
PLOS Medicine. 2016 Jul 19;13(7):e1002087. (Imamura F et al.)

Mindful Eating as a Tool for a Healthy, Sustainable Diet

Healthy lifestyles and diets encompass not only the types and amounts of foods eaten, but also the way they are eaten, emphasizing mindfulness, community, culture, and the pleasures of the table. In this review, researchers analyze the existing studies evaluating mindful eating. Although mindful eating practices are typically used to help patients with disordered eating, the authors note that mindful eating could also be a strategy to help consumers move toward a more sustainable diet, by cultivating an awareness of the environmental impact of food choices. The researchers also note that a more standardized definition and assessment tool for mindful eating could help move the research forward.
Journal of the Academy of Nutrition and Dietetics. 2016 Jul;116(7):1081-6. doi: 10.1016/j.jand.2016.03.013. (Fung TT et al.)

Butter is NOT Back – Unsaturated Fats Best for Lower Mortality

In the one of the most powerful studies to date regarding dietary fats and health, Harvard researchers analyzed the eating patterns of 126,00 adults for up to 32 years. They found that eating more unsaturated fat (the type of fat in olive oil, nuts, and seeds) was linked with lower mortality, but that eating more saturated and trans fats (the types of fats in butter, red meat, and highly processed snack foods) was linked with higher mortality. In fact, replacing just 5% of calories from saturated fat with the same amount of polyunsaturated fat (like salmon, flax seeds, and walnuts) or monounsaturated fat (like olive oil and avocados) was associated with a 27% and 13% lower risk of death from all causes, respectively.
JAMA Internal Medicine. 2016 Jul 5. (Wang DD et al.) [Epub ahead of print.]

Home Cooked Meals Linked with Lower Diabetes Risk

Home-cooked meals are a hallmark of the old ways of eating, linked with countless social and economic benefits. To see if eating more home cooked meals is associated with lower rates of disease, researchers analyzed eating patterns and health data from nearly 100,000 adults in the Nurses Health Study for up to 36 years. They found that those eating 11-14 homemade lunches or dinners each week (so eating both a homemade lunch and a homemade dinner nearly every day) had a 13% lower risk of developing Type 2 diabetes compared to those who ate less than six homemade lunches or dinners each week.
PLoS Medicine. 2016 Jul 5;13(7):e1002052. (Zong G et al.)

Whole Grains Linked with Longevity

In a meta analysis, Harvard scientists analyzed the whole grain intake and rates of death for 786,076 adults across 14 studies. Compared to people who ate the least whole grains, people who ate the most whole grains had a 16% lower risk of death from all causes, an 18% lower risk of death from heart disease, and a 12% lower risk of death from cancer. However, the significantly lower risk of cancer death was only seen in people who ate at least 30g whole grains per day (the amount in about ½ cup cooked brown rice, or 2 slices of 100% whole grain bread). The researchers also observed a dose response relationship, meaning the more whole grains someone ate, the less likely they were to die during the study period. According to the scientists, these results “strongly supported the current Dietary Guidelines for Americans,” which encourage at least 3 servings of whole grains per day (totaling at least 48g whole grains).
Circulation. 2016 Jun 14;133(24):2370-80. (Zong G et al.)

Whole Grains Linked with Lower Risk of Heart Disease, Cancer, Respiratory Disease, Infectious Diseases, Diabetes, and Early Death

Researchers in Europe and the US analyzed 45 studies (ranging from 245,012 to 705,253 participants each) in a meta analysis to understand the relationship between whole grains and health. Compared to people who ate the least whole grains, people who ate the most whole grains had a 16-21% lower risk of heart disease, an 11% lower risk of cancer, and an 18% lower risk of death from all causes, as well as a 19% lower risk of death from respiratory disease, a 36% lower risk of death from diabetes, a 20% lower risk of death from infectious disease, and a 21% lower risk of death from all non-cardiovascular, non-cancer causes. The researchers also found that a 90g increase in whole grain foods per day (about 3 servings) was linked with a 19-22% lower risk of heart disease, a 15% lower risk of cancer, and a 17% lower risk of death from all causes, and that “even moderate increases in whole grain intake could reduce the risk of premature mortality.” Whole grain bread, whole grain cereals, total grains, total cereals, total bread, pasta, and bran, were also singled out for their relationship with lower rates of various diseases and/or early death. The researchers conclude that their findings “strongly support existing dietary recommendations to increase whole grain consumption in the general population.”
British Medical Journal. 2016 June 14;353. (Aune D et al.)

Healthy Plant Foods (Whole Grains, Pulses, Vegetables, Nuts, etc.) May Lower Diabetes Risk

Plant-based diets are linked with numerous health benefits, but you must take care to choose healthier plant foods close to nature, that haven’t been refined or include lots of added sugars. To investigate the importance of this point, Harvard researchers analyzed the eating habits of 195,727  adults across three large cohorts, and tracked their health records for decades. Eating a healthy plant based diet (with whole grains, fruits, vegetables, nuts, legumes, vegetable oils, tea, and coffee) was linked with a 34% lower risk of type 2 diabetes, while eating a less healthy plant based diet (with fruit juice, sugary drinks, refined grains, potatoes, and desserts) was linked with a 16% higher risk of diabetes.
PLoS Medicine. 2016 Jun 14;13(6):e1002039. (Satija A et al.)

Plant-Based Diets Linked with Lower Risk of Type 2 Diabetes

Plant-based diets show promise for a number of . Using more than 20 years of health and nutrition data, researchers scored the diets of more than 200,000 U.S. adults to see how closely they aligned with a plant based diet (mostly plant foods, minimal animal foods), a healthy plant based diet (emphasizing whole grains, fruits, vegetables, nuts, and legumes), or an unhealthy plant based diet (emphasizing refined grains, juice, and sweets). Plant-based diets were associated with a 20% lower risk of type 2 diabetes, while healthy plant based diets indicated an even greater risk reduction (34%). On the other hand, unhealthy plant based diets were linked with a 16% increased risk of type 2 diabetes. The researchers note that “plant-based diets need not completely exclude animal foods,” as those with the highest healthy plant based diet scores averaged 4 servings of animal foods per day, compared to 5-6 servings per day in those with the lowest scores. 
PLoS Medicine. 2016 Jun 14;13(6):e1002039. (Satija A et al.)

Mediterranean Diet May Prevent Breast Cancer Relapse

In a study of 307 Italian women with early breast cancer, who had undergone treatment and were in complete remission, researchers assigned 199 of the women to their normal diet, but with healthy advice from a dietitian, while the other 108 women were assigned to a Mediterranean diet (with lots of fruits and vegetables, fish, olive oil, and up to one glass of wine per day). After 3 years, breast cancer returned to 11 patients from the standard diet group, but none in the Mediterranean diet group relapsed. This indicates a statistically significant reduced risk of breast cancer recurrence for those following a Mediterranean diet.  
Journal of Clinical Oncology. 2016 ASCO Annual Meeting. 2016 June 3-7;34(15):Suppl:e13039. (Biasini C et al).

Fiber Linked with Healthy Aging

Researchers analyzed 10 years of extensive health and nutrition data in a study of more than 1,600 Australian adults, to see how carbohydrate nutrition (Glycemic Index, Glycemic Load, total carbs, sugars, and fiber) relates to successful aging. The researchers defined successful aging as absence of disability, depression, cognitive problems, respiratory problems, or chronic disease (like heart disease or cancer). Adults eating the most total fiber were significantly more likely to age successfully. Additionally, those eating the most cereal fiber (the type of fiber in whole grains) were 78% more likely to age successfully than those eating the least, and those eating the most fruit fiber were 64-81% more likely to age successfully. Those eating a higher Glycemic Index at the beginning of the study were more likely to die throughout the study, but neither Glycemic Index, Glycemic Load, total carbohydrate, nor sugar intake were significantly associated with successful aging. 
The Journals of Gerontology: Series A, Biological Sciences and Medical Sciences. 2016 Jun 1. pii: glw091. [Epub ahead of print] (Gopinath B et al.)

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