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Mediterranean Diet Linked with Fewer Signs of Pre-Cancerous Colorectal Polyps

The Mediterranean Diet is known to be protective against chronic diseases and certain cancers, but researchers wonder if certain elements of the Mediterranean diet are especially protective. In a study of 808 adults undergoing routine colonoscopies, researchers found that those who reported more closely following a Mediterranean diet were more likely to have clear (healthy) colonoscopies, noting a dose-response relationship (meaning the more elements of a Mediterranean diet that people followed, the lower the risk of having advanced colorectal polyps in their colonoscopies — a risk factor for colorectal cancer). When looking at individual food groups, the researchers noted that having more fruit and fish, and fewer sodas appeared to be the most important factors, as each of these factors was linked with more than a 30% lower risk of pre-cancerous polyps. Taken together, eating more fruit and fish, and drinking fewer sodas is linked with 86% reduced odds of pre-cancerous polyps. (Note that findings presented at meetings are typically viewed as preliminary until they’ve been published in a peer-reviewed journal.)
Presented at the European Society for Medical Oncology’s 19th World Congress on Gastrointestinal Cancer. Barcelona, Spain. June 30, 2017. (Fliss Isakov N et al.)

Vegetable Protein Linked with Lower Risk of Early Menopause

Early menopause is linked with health risks, like heart disease, so strategies to prolong fertile years in women are an important area of research. In a study of 85 women, women with the highest plant protein intake had a 16% lower risk of early menopause (defined as menopause before age 45) compared to women with the lowest intake in the group. Plant foods with protein include beans, peas, nuts, seeds, lentils, whole grains and soy foods. Overall animal protein intake was unrelated to risk of early menopause, but red meat intake was associated with a 12% higher risk of early menopause. Additionally, one serving per day of pasta, dark bread, or cold cereal was also associated with lower risk of early menopause, at 36%, 7%, and 18%, respectively.
American Journal of Epidemiology. 2017 June 24. [Epub ahead of print] (Boutot ME et al.)

Whole Grain Foods Improve Blood Sugar Management After Meals

Whole grains are thought to help prevent type 2 diabetes, but researchers want to learn more about this protective effect. In a review of 14 randomized controlled studies, scientists found that whole grain foods led to better post-meal blood sugar management than refined grain foods. However, the medium- and long-term effects (6 weeks or more) on fasting blood sugar were not significantly different between whole grain and refined grain meals. 
Nutrients. 2017 Jul 19;9(7). pii: E769. (Marventano S et al.)

Workplace Mediterranean Diet Program Improves Food Choices among Workers

Even in Italy, workers are starting to opt for unhealthy Western food choices, in place of traditional Mediterranean meals. To combat this trend, researchers in Italy piloted a health program within worksite cafeterias of a large industrial corporation. Handouts, posters, and other promotional material decorated the cafeteria to encourage consumption of healthy foods like vegetables and whole grains. Nutritionists also worked with the food service staff to modify recipes to make them healthier. At the end of the pilot, after analyzing food choices from 738 employees (half office workers, half plant workers) there was a higher purchase rate of dishes based on whole grains, legumes, fish, and poultry and a lower purchase rate of dishes based on refined grains, red meats, eggs and cheese. This trend persisted up to three years after the intervention. There was also better adherence to the national Italian recommendations for saturated fat, cholesterol, sugars and fiber after the study. The authors conclude that this could be a good model for other workplace nutrition programs, especially given that it cost the employer very little, and did not take up too much of the foodservice employees’ time.
International Journal of Food Sciences and Nutrition. 2017 Jun;69(1):117-124. (Vitale M et al.)

Butter isn’t “back,” according to the American Heart Association

In order to clear up confusion about how different dietary fats relate to heart health, the American Heart Association published a Presidential Advisory on Dietary Fats and Cardiovascular Disease. In this paper, the researchers reviewed randomized controlled trials (the gold standard of nutrition research) as well as prospective observational studies (following large groups of people over long periods of time and noting their health outcomes). After reviewing all of the evidence, they concluded that replacing saturated fat (the types of fats found in red meat, butter, and milk) with polyunsaturated fat (found in fish, nuts, and seeds) can lower the risk of heart disease by 30%, which is on par with what cholesterol lowering medications can achieve. Similarly, they found that eating more monounsaturated fat (found in avocados, olive oil, and canola oil), more polyunsaturated fat, and less saturated fat is linked with lower rates of heart disease. Saturated fat is also linked with higher rates of “bad cholesterol” (LDL), which is thought to build up in artery walls and pose a risk for heart disease. These findings are in line with healthy dietary patterns around the world, including the Mediterranean diet.
Circulation. 2017 Jun 15. [Epub ahead of print.] (Sacks FM et al.)

Descriptive, Indulgent Names Can Help Nudge Customers Towards Vegetables

Taste is one of the top motivators for making food decisions, so appealing to peoples’ senses (rather than their desire to be healthy) could be a smart approach to nudge people towards more nutritious choices. To see if changing the name of a vegetable dish (without changing the recipe) affected interest in vegetables, researchers offered a range of different vegetables using different descriptors to 27,933 Stanford University cafeteria diners over an academic quarter. They found that the veggies with indulgent labeling (e.g. “dynamite chili and tangy lime seasoned beets”) were chosen 25% more often than those with basic labeling (e.g. “beets”); 35% more than healthy positive labeling (e.g. “high-antioxidant beets”); and 41% more than those with healthy restrictive labeling (e.g. “lighter-choice beets with no added sugar”). The indulgent labeling also significantly increased the amount of vegetables eaten, even though the recipe was not altered at all.
JAMA Internal Medicine. 2017 June 12. [Epub ahead of print.] (Turnwald BP et al.)

Lose Weight (and Fat) with a Vegetarian Diet

Vegetarians tend to weigh less than omnivores, but researchers wonder whether their body fat distribution might be different as well. To test this relationship, researchers randomly assigned 74 adults with type 2 diabetes to either a vegetarian or non-vegetarian diet for 6 months. Both diets were restricted by 500 calories per day, and the second half of the study included aerobic exercise for both groups. The vegetarian diet was almost twice as effective at weight loss (13.7 pounds lost) as the conventional calorie-restricted diet (pounds lost). The vegetarian diet also reduced subfascial fat (a type of internal fat related to poor blood sugar control) by 0.82 cm squared, but the conventional weight-loss diet did not.
Journal of the American College of Nutrition. 2017 June 10;1-6. (Kahleova H et al.)

Substituting Refined Grains with Whole Grains During Gestational Diabetes Linked with Less Childhood Obesity

Foods that moms choose during pregnancy may have an impact on their children’s health down the line. In a study of more than 500 mother-child pairs in Denmark, in which all of the moms were diagnosed with gestational diabetes (diabetes during pregnancy), Harvard researchers found that substituting 1 serving of refined grains per day with whole grains in the mom’s diet during pregnancy was associated with a 10% lower risk of the child being overweight or obese at age 7. They also found that eating more than 4.3 servings of refined grains per day during pregnancy was linked with nearly double the risk of children becoming overweight or obese at age 7 compared to those who ate fewer than 1.8 servings of refined grains per day. These results were especially strong in kids who were breastfed for less than 6 months.
American Journal of Clinical Nutrition. 2017 June 7. [Epub ahead of print.] (Zhu Y et al.)

Mediterranean Diet Is Linked with Specific Patterns in Gut Microbiota

Although the science is still young, researchers are finding that the foods we eat may influence the bacteria that inhabit our gut. To see how the Mediterranean Diet relates to the gut microbiome, researchers analyzed the diet and gut microbiome of 120 Greek adults. Participants most closely following the Mediterranean diet had lower E.coli levels and a higher bifidobacteria: E. coli ratio, among other favorable microbiome characteristics.
British Journal of Nutrition. 2017 June 5;117(12):1645-1655. (Mitsou EK et al.) 

Fiber Linked with Less Knee Pain Worsening and Less Symptomatic Osteoarthritis

Osteoarthritis is a painful joint condition in which the flexible tissues at the ends of bones get worn down. To see how eating patterns might relate to joint pain in this condition, scientists analyzed the diets of 5,227 US adults (average age = 61) with (or at risk of) osteoarthritis. Those eating 20.6 grams of fiber per day were 30% less likely to develop symptomatic osteoarthritis than those eating only 8.6 grams of fiber per day, and scientists noted a dose-response relationship (meaning that higher fiber intakes are correlated with a lower risk of symptomatic osteoarthritis). Similarly, the researchers found that those eating the most cereal fiber (the type of fiber in whole grains) had a 14% lower risk of knee pain worsening than those eating the least (8.4 grams vs 2.8 grams). However, results were not statistically significant for other types of fiber (such as fiber from fruit or nuts).
Annals of the Rheumatic Diseases. 2017 May 23. [Epub before print.] (Dai Z et al.) 

Plant-Based Diet Can Reduce Obesity Risk by 43%

Nearly every healthy diet around the world is centered on a foundation of colorful produce. To see how eating more plant foods relates to obesity risk, scientists analyzed the diets of 16,000 healthy (non-obese) adults in Spain. Those eating the most plant-based diets (high in fruits, vegetables, grains, nuts, olive oil, and pulses, and low in meat, dairy, seafood, and other animal products) had a 43% lower risk  of becoming obese throughout the 10-year study than those with the most animal-based diets, even after controlling for age, physical activity, and other demographic factors. (Note that findings presented at meetings are typically viewed as preliminary until they’ve been published in a peer-reviewed journal.)
Presented at the European Congress on Obesity. Porto, Portugal. May 18, 2017. (Sanz J et al.)

Pasta Meals Linked with Better Blood Sugar Response

Many are surprised to learn that pasta has a low glycemic index, meaning that it doesn’t spike your blood sugar as much as some other carbohydrate foods, like bread or potatoes. To see how pasta meals relate to health in a broader context, researchers analyzed 18 studies comparing the effects of pasta meals to other types of meals. They found that pasta meals are linked with a lower post-meal blood sugar response than bread- or potato-based meals. However, more research is needed to study how different types of meals relate to cardio-metabolic disease.
Nutrition, Metabolism, and Cardiovascular Diseases. 2017 Jul 18. pii: S0939-4753(17)30160-6. (Huang M et al.)