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Beans, Grains, and Fiber Linked with Lower Risk of Breast Cancer

It’s important to get your fiber from a variety of foods, since different sources of fiber are associated with different health benefits. Researchers analyzed the eating patterns of 2,135 patients with breast cancer and 2,571 controls to see how different foods and fibers might relate to breast cancer risk. Those eating the most fiber (more than 26.5 grams per day) were 25% less likely to have breast cancer than those eating less than 15.2 grams of fiber per day. Similarly, those eating the most beans (more than 3.9 oz per day) and grains (more than 13.8 oz per day, of both whole and refined grains) were 19% and 18% less likely to have breast cancer, respectively, than those eating the least amount of beans and grains.
Cancer Medicine. 2018 Mar 23. [Epub ahead of print] (Sangaramoorthy M et al.)

Mediterranean Diet Linked with Healthier Bones and Muscles After Menopause

Women lose bone mass during menopause, so strategies to prevent osteoporosis in this population are of utmost importance. In a study of 103 post-menopausal women (average age 55), researchers analyzed their diet and body composition. Most closely following a Mediterranean diet was linked with better muscle mass and greater spine bone mineral density than those not eating Mediterranean foods like olive oil, fish, and grains. (Note that findings presented at meetings are typically viewed as preliminary until they’ve been published in a peer-reviewed journal.)
Presented at ENDO 2018: The Endocrine Society Annual Meeting. Chicago, Illinois. March 20, 2018.

Brown Rice Stays in Stomach Longer than White Rice, Good for Blood Sugar and Nutrient Absorption

Brown rice and other whole grains have been long known to “stick to your ribs,” and new research explains why. In a small study, 10 healthy adults were fed various types of white rice and brown rice over 7 weeks, with a breath hydrogen test to track how long their stomach stayed full. The brown rice samples all stayed in the stomach significantly longer than the white rice samples, likely because the bran takes longer to break down. Slow stomach emptying helps the body better regulate how nutrients are digested and absorbed, and helps create a more gentle blood sugar response (rather than a blood sugar spike).
European Journal of Clinical Nutrition. 2018 Mar;72(3):367-373. (Pletsch EA et al.)

Delayed Gluten Introduction May Be Linked with Type 1 Diabetes Risk

In a study of 8,676 babies with a genetic risk for type 1 diabetes, researchers took blood samples every 3 months for at least 9 months after birth and analyzed their diet. Every 1-month delay in gluten introduction was linked with a significantly higher risk of the immune system attacking the pancreatic cells that are important for blood sugar regulation (as measured by islet autoimmunity) as well as higher levels of insulin autoantibodies, which are predictors of type 1 diabetes. In fact, introducing gluten after 9 months was linked with a 57% higher risk of islet autoimmunity than introducing gluten between 4-9 months of age. The researchers suggest that the timing of gluten be studied further, so that healthcare providers can more confidently suggest a recommended window.
Diabetes Care. 2018 Mar;41(3):522-530. (Uusitalo U et al.)

High Fiber Diet Promotes Select Gut Bacteria to Better Manage Diabetes

In line with many other countries, the usual care for patients with diabetes in China is education about balanced diets and blood sugar management strategies. In a small study, 43 patients with diabetes were randomly assigned to either these standard recommendations, or a high-fiber diet with whole grains and traditional Chinese medicinal foods. Both groups significantly improved their blood sugar (as measured by HbA1c) over the 12-week study, but significantly more people in the whole grain group (89% vs 50%) got their blood sugar to a well-managed level (HbA1c < 7%). To see how gut microbes might play a role, researchers also analyzed the gut bacteria of the participants. They found that the fiber from whole grains stimulated select bacteria to produce short chain fatty acids, which in turn, helped the body better manage blood sugar.
Science. 2018 March 9;6380(359):1151-1156. (Zhao L et al.)

Suggested Mechanisms Behind the Health Benefits of the Mediterranean Diet

While the health benefits of the Mediterranean diet are well-known, the precise mechanisms behind these benefits are unclear. In this review, researchers identified 5 mechanisms which may explain the benefits of the Mediterranean diet. Due to the high consumption of healthy fats and fiber, the Mediterranean diet improves cholesterol and decreases the risk of cardiovascular disease. The Mediterranean diet is naturally high in antioxidants, which can help decrease the inflammation associated with heart disease, cancer, and dementia. The Mediterranean diet is also naturally lower in calories but higher in vitamins and minerals than the typical western diet, which may lower the production of hormones and growth factors that are involved in the development of cancer. The emphasis of plant proteins over animal proteins in the Mediterranean diet may help explain why this diet is associated with a lower risk of type 2 diabetes. Finally, researchers found that the high fiber content of the Mediterranean diet promotes the growth and diversity of good bacteria in the gut.
Journals of Gerontology: Biological Sciences. 2018 Mar 2;73(3):318-326. doi: 10.1093/gerona/glx227. (Tosti, V. et al)

Mediterranean Diet Linked with Lower Risk of Agility and Mobility Problems in Aging

Maintaining healthy physical function is important to help seniors live comfortably and independently as they age. To see if diet relates to physical function, researchers analyzed the eating patterns and physical function of 1,630 seniors (ages 60+) in Spain. Those most closely following a Mediterranean Diet (as measured by MEDAS, the Mediterranean Diet Adherence Screener) were 33% less likely to have problems with agility, 31% less likely to have problems with mobility, and 40% less likely to have decreased overall physical function. Note that when eating patterns were analyzed by MDS (the Mediterranean Diet Score, which is less thorough then MEDAS, as it covers fewer foods and doesn’t have specific cut-off points for each food group), the relationship was only statistically significant for physical functioning.
The Journals of Gerontology. 2018 Mar 2;73(3):333-339. (Struijk EA et al.)

Synthetic Folate (Found in Enriched Grains) Linked with Food Allergies in Kids

In the US, most refined grains are enriched with high levels of folic acid, to help prevent neural tube defects in children, such as spina bifida. However, new research raises questions about the benefits of high levels of synthetic folate in children. In a study of 1,394 children, the kids who developed food allergies were found to have higher levels of UMFA, which is a derivative of synthetic folate. The authors conclude that “more research is needed to conclude whether mothers should consider consuming different sources of folate, like leafy green vegetables, citrus fruits, beans or lentils instead of synthetic forms of folate.” (Note that findings presented at meetings are typically viewed as preliminary until they’ve been published in a peer-reviewed journal.)
Presented at American Academy of Allergy, Asthma, & Immunology Annual Meeting. Orlando, Florida. March 2-5, 2018.

Mediterranean Diet Linked with Healthy Aging

When it comes to aging healthfully, no eating pattern quite stacks up to the Mediterranean diet. In this study, researchers analyzed the eating patterns of more than 3,000 middle-aged French adults who were free of chronic disease and monitored their health over the next 15 years. Those most closely following a Mediterranean diet in middle age were significantly more likely to age healthfully, meaning that they were free of chronic disease, depression and pain, were able to live independently.
The Journals of Gerontology: Series A.  2018 Mar 2;73(3):347-354. (Assmann KE et al.)

More Research Needed on Mediterranean Diet & Cognition

To get a better understanding of how the Mediterranean diet relates to brain health, researchers analyzed existing randomized controlled trials (the “gold standard” of nutrition research, where participants are randomly assigned to one diet or another, so that researchers can look for causal relationships). Thus far only 5 randomized controlled trials on the Mediterranean diet and cognition have been published, with mostly insignificant results. However, the researchers did note that the most well-designed studies (using PREDIMED data) are the studies that found a protective effect on dementia risk and cognition, indicating that the Mediterranean diet might hold promise in these areas. More research is needed.
American Journal of Clinical Nutrition. 2018 Mar 1;107(3):389-404. (Radd-Vagenas S et al.)

Both Mediterranean and Vegetarian Diets Effective for Weight Loss

From Mediterranean to vegetarian, many of the world’s healthiest diets actually have more similarities than differences, so it’s not surprising to find that both these diets can be an effective path to weight loss. In this study, researchers randomly assigned 118 overweight adults who normally eat meat to either a lower calorie Mediterranean diet or a lower calorie vegetarian diet for 3 months. After a two-week assessment, the participants then switched to the other diet for 3 months. Participants lost about 4 pounds during each diet, and both diets were also effective at decreasing body fat. The only significant difference between the diets was that the vegetarian was slightly more effective in lowering bad (LDL) cholesterol, while the Mediterranean diet was slightly more effective in lowering triglycerides (a type of fat in the blood).
Circulation. 2018 Feb 26. (Sofi F et al.) [Epub ahead of print]

Substituting Whole Grains for Refined Linked with Lower Risk of Death, Cancer Reoccurrence

The link between whole grains and colorectal cancer prevention is well established, but researchers wonder how this relationship plays out in patients who have already been diagnosed with colon cancer. In this study, researchers analyzed the eating habits and health status of 1,024 patients with stage III colon cancer. After 7 years, patients eating 3 or more servings of refined grains per day had a significantly higher risk of cancer reoccurrence or death from any cause. Replacing 1 serving of refined grains with 1 serving of whole grains daily was linked with a 23% lower risk of cancer reoccurrence or death from any cause. Eating 3 or more servings of whole grains daily trended towards lower risk as well, but the relationship was not statistically significant.
JNCI Cancer Spectrum. 2018 Feb;2(2):pky017. (Brown JC et al.)

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