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Mediterranean Diet Lowers Blood Pressure

The Mediterranean Diet is widely praised for its role in supporting heart health. To see how following a diet rich in fruits, vegetables, nuts, olive oil, and fish, and low in processed foods and red meats, affects blood pressure, researchers randomly assigned 166 elderly Australian adults to either a Mediterranean Diet or their regular habitual diet. After six months, the Mediterranean Diet group had lowered systolic blood pressure (the number on top, representing the pressure your heart uses while beating) and improved functioning of endothelial cells (which line the inside of blood vessels) as compared to the habitual Australian diet group.
American Journal of Clinical Nutrition. 2017 Jun;105(6):1305-1313. (Davis CR et al.)

Rural Ghanaians Eat More Roots, Tubers, Plantains than Ghanaians Living in Europe

West African immigrants living in Europe are more affected by obesity and diet-related disease than the European population or their counterparts in West Africa, as they replace traditional foods with a more highly processed, Western Diet. To better understand this nutrition transition, researchers analyzed the diets of 4,543 Ghanaians living in urban Ghana, rural Ghana, and Europe (Amsterdam, Berlin, and London). Ghanaians living in Europe had higher BMIs than those living in Ghana and got more of their calories from fat and protein, whereas Ghanaians living in Ghana got more of their calories from carbohydrates and ate more fiber (especially in rural Ghana). Though there were many differences in eating habits among the participants, those living in rural Ghana tended to eat more roots, tubers, plantains, and fermented corn products; those living in urban Ghana tended to eat more rice, pasta, meat, and fish; and those living in Europe tended to eat more sweets, dairy, potatoes, chicken, whole grains, oils and margarine.
Food and Nutrition Research. 2017 Jul 6;61(1):1341809. (Galbete C et al.)

Low-Carb Diet Not Well Suited for Those Without Diabetes, Pre-Diabetes

While there is no one-size-fits-all weight loss plan that works for everyone, it seems that a low Glycemic Load or low carbohydrate diet makes little difference for most people who don’t have diabetes (or pre-diabetes). Researchers analyzed data from 3 different experiments (high Glycemic load vs low Glycemic Load, lots of whole grains vs few whole grains, and low fat vs. low carbohydrate) and noted whether the weight change differed between people with insulin sensitivity issues (such as diabetes or pre-diabetes). Eating a high Glycemic Load diet resulted in significantly more weight gain in people whose bodies don’t respond well to insulin (the hormone that helps control blood sugar), compared to those without insulin sensitivity issues. Similarly, people with insulin sensitivity problems lost more weight on a New Nordic Diet (high in whole grains) or a high-fat, low-carbohydrate diet. However, people without diabetes or pre-diabetes lost more weight on a high-carbohydrate, low-fat diet.  
American Journal of Clinical Nutrition. 2017 July 5. [Epub ahead of print.] (Hjorth MF et al.)

 

Healthy Diets (Like Med Diet) Associated with Longer Lives

Can an apple a day keep the grim-reaper away – at least for a while? To find out how diet relates to mortality, researchers analyzed the diets of 47,994 women and 25,745 men. They used scores from the Alternate Healthy Eating Index, the Alternate Mediterranean Diet, and the Dietary Approaches to Stop Hypertension (DASH) diet to determine diet quality. They found that a 20-percentile increase in any of these three diet-quality scores was associated with a reduced risk of death from any cause. Specifically, a 20-percentile increase in diet-quality score was associated with a 25% reduced risk of death from cardiovascular disease when assessed by the Alternate Healthy Eating Index, 7% when assessed by the Mediterranean Diet score, and 4% when assessed by the DASH score. Overall, a healthful diet full of whole grains, vegetables, fruit, and fish is linked with a longer life.
New England Journal of Medicine. 3 July 2017;377(2):143-153. (Sotos-Prieto M et al.)

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.)

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