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Mediterranean Diet Improves Function of Good Cholesterol

HDL is often referred to as good cholesterol, because it helps take “bad” (LDL) cholesterol from the bloodstream back to the liver for removal, protects blood vessels, and acts as an antioxidant. We used to only be able to measure the amount of HDL, but now, scientists are able to measure how well the HDL is functioning as well. To see how a Mediterranean diet affects HDL function, researchers analyzed data from 296 participants in the PREDIMED trial (a randomized, controlled study where people at risk of heart disease were assigned to either a Mediterranean diet with nuts, a Mediterranean diet with olive oil, or a low fat diet). Both Mediterranean diet groups improved cholesterol efflux capacity (how well the LDL is transported out by the HDL). However, the olive oil group also had improved HDL antioxidant properties, and improved blood vessel protection.
Circulation. 2017 Feb 14;135(7):633-643. (Hernaez A et al.) 

Whole Grains May Help Your Body Burn More Calories

Whole grains are often associated with lower body weights, and new research is uncovering why. In a randomized trial, scientists assigned 81 healthy adults in Boston to diets with either whole grains or refined grains for 6 weeks, keeping all other foods and nutrients consistent between the groups. Although the diets were designed to be isocaloric (meaning that people were supposed to maintain their same body weight), the resting metabolic rate (how many calories your body burns at rest) became significantly higher (by 43 calories) in the whole grain group. In fact, the whole grain group significantly improved their metabolism over the 6-week study compared with the refined grains group, burning 92 more calories per day. The researchers suspect that this is partly due to the fact that the whole grain group excreted more energy in the stool, and had more frequent bowel movements.
American Journal of Clinical Nutrition. 2017 Feb 8. pii: ajcn139683. [Epub ahead of print.] (Karl JP et al.)

Whole Grains Can Improve Gut Microbiota

Researchers randomly assigned 81 healthy adults in Boston to diets with either whole grains or refined grains for 6 weeks, keeping all other foods and nutrients consistent between the groups. The researchers found that making all of your grains whole is linked with “modest, positive effects on gut micriobiota,” (due to higher concentrations of “good” gut microbes and short chain fatty acids – an indicator of colon health and dietary fiber breakdown) as well as increased stool weight and stool frequency.
American Journal of Clinical Nutrition. 2017 Feb 8. pii: ajcn146928. [Epub ahead of print.] (Vanegas SM et al.)

Traditional Ogimi Diet Filled with Potentially Neuroprotective Foods

Ogimi is a village in Okinawa, Japan famous for a remarkably high number of people who live healthfully into their 80s, 90s, and 100s. In this study researchers interviewed elderly Ogimi residents to learn about the most commonly eaten foods. Soy foods (like tofu) and seaweed make up a substantial portion of the diet. In fact, 13 of the 25 most frequently consumed foods are species of seaweed. The researchers suspect that the L-serine amino acids in the Ogimi diet (found in foods like tofu and seaweed) may partially explain the link with longevity, as some animal studies suggest that L-serine amino acids may be neuroprotective.
Current Nutrition Reports. 2017;6(1):24-31. (Cox PA et al.)

Mediterranean Diet May Help Improve Depression

To see how food might play a role in treating depression, Australian scientists randomly assigned 56 adults with moderate to severe depression to either 7 hours of dietitian-led counseling about a modified Mediterranean diet, or 7 hours of social support (keeping participants company, without using psychotherapy strategies) over the course of 12 weeks. The adults in the nutrition counseling group improved their diets by eating significantly more servings of whole grains, fruit, dairy, olive oil, pulses, and fish. After 12 weeks, 32% of the nutrition group and 8% of the social support group improved their depressive symptoms enough to achieve remission, and the nutrition group also scored significantly better on various markers of depression.
BMC Medicine. 2017 January 30;15:23. ( Jacka FN et al.)

Mediterranean Diet Linked with Less ADHD in Kids

Attention-deficit/hyperactivity disorder (ADHD) seems to be on the rise, so health experts wonder if diet might be related. To test this hypothesis, researchers in Spain matched 60 children newly diagnosed with ADHD to 60 children without ADHD (of the same age and sex), and analyzed their eating habits based on how closely they follow a Mediterranean diet. Children most closely following a Mediterranean diet (eating a second serving of fruit daily, eating vegetables daily, and eating pasta or rice almost every day) were significantly less likely to have ADHD. Children with ADHD were also more likely to eat more fast food, soft drinks, and candy, and were more likely to skip breakfast.
Pediatrics. 2017 Jan 30. pii: e20162027. [ePub ahead of print.] (Rios-Hernandez A et al.)

Whole Grains & Fiber Linked with Less Colorectal Cancer

Because colorectal cancer forms in the large intestine, diet is thought to be a potential risk factor. To see how food fits into the puzzle, scientists at Harvard analyzed the eating patterns and health markers of 137,217 adults for more than two decades. Those eating a healthy diet rich in fiber and whole grains were significantly less likely to develop a certain type of colorectal cancer (Fusobacterium nucleatum–positive, but not Fusobacterium nucleatum-negative) than those eating a “Western diet” rich in red meat, refined grains, and dessert. Fusobacterium nucleatum is a type of gut bacteria thought to contribute to colorectal cancer, as it’s often elevated in colorectal cancer patients. Based on their findings, the scientists suspect that the cancer-protective effect of fiber and whole grains may have to do with their role in improving the gut microbiome.
JAMA Oncology.  2017 Jan 26. [Epub ahead of print.] (Mehta RS)

Spice & Herb Usage Varies by Demographic Group

Using spices and herbs to flavor vegetables is a hallmark of traditional diets around the world, but not all Americans today are taking full advantage of these culinary treasures. Researchers in Illinois surveyed 1,042 US adults, census representative in terms of sex, age (except for the 70+ group), income, and geographic region. They found that millennials (age 18-29) and Asian Americans were most likely to use more spices and herbs more frequently, while low-income, male, older (age 50+), and white respondents were less likely to take advantage of spices & herbs when cooking vegetables. The most popular among the list of 20 spices and herbs were garlic, oregano, basil, and paprika.
American Journal of Health Behavior. 2017 Jan;41(1):52-60. (Nikolaus CJ et al.)

Infants Accept Partially Whole Grain Cereal

Early exposure to whole grain foods can shape food preferences later in life, so researchers wonder if it may be worthwhile to start with infants. Infant cereals are one of the first solid foods given to babies to compliment breast milk or formula and are often made from refined grains like white rice or pearled barley. In this study, researchers in Spain worked with parents of 81 infants (4-24 months old) to test the acceptability of 30% whole grain infant cereals (made with whole wheat), compared with a popular refined infant cereal. (Whole wheat was chosen to comply with European infant legislation, to make sure that the amount of fiber was appropriate.) After trying each of the cereals for 3 days in a row, infants were just as likely to accept and finish the whole grain cereal as they were the refined cereal. The researchers concluded that infant cereals are an opportunity to expose young people to whole grains earlier in life, to build a taste for them.
Nutrients. 2017 Jan 13;9(1). pii: E65. (Haro-Vicente JF et al.)

Mediterranean Diet Linked with Less Diabetes After Kidney Transplant

Kidney transplants are used to help people with end stage renal disease, but the transplant also puts patients at risk for developing diabetes. To see how diet might be related, researchers followed 468 Dutch adults who had received a kidney transplant, analyzing their health outcomes and eating patterns for about 4 years. Those most closely following a Mediterranean diet were 4 times less likely to get new-onset diabetes after transplantation. Additionally, closely following a Mediterranean diet was also linked with a two times lower risk of all-cause mortality, compared with those not closely following a Mediterranean diet.
BMJ Open Diabetes Research & Care. 2017 Jan 13;5(1):e000283. (Oste MCJ et al.)

Slow Cooking Sofrito with Onion Helps Improve Antioxidant Capacity

Nutrition researchers are shedding light on synergies that home cooks have intuitively known for centuries: that traditional food pairings and preparations can offer even greater benefits than the ingredients by themselves. Sofrito, a delicious tomato-based puree used in several Latin American, Caribbean, and Spanish soups, stews, and sauces, is one such example of a healthy food tradition. Simmering the sofrito slowly, over a longer period of time, and including an onion in the recipe are not just important for the development of flavor — researchers in Spain found that these steps actually improve the antioxidant capacity and bioavailability of the lycopene, a healthy plant compound found in tomatoes.
Food Research International. 2017 January 11. [Epub before print.] (Rinaldi de Alvarenga JF et al.)

Mediterranean Diet Linked with Less Age-Related Brain Shrinkage

As people age, their brains gradually shrink over time. But certain lifestyle habits may be able to slow this loss. In a study of more than 1,000 elderly Scottish adults, researchers found that those most closely following a Mediterranean diet lost significantly less total brain volume over the 3-year study period than those who didn’t eat a Mediterranean diet. The authors also found that “fish and meat consumption does not drive this change, suggesting that other components of the [Mediterranean Diet] or, possibly, all of its components in combination are responsible for the association.”
Neurology. 2017 Jan 4. pii: 10.1212/WNL.0000000000003559.[Epub ahead of print](Luciano M et al.)

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