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Whole Grain Wheat and Rye Both Linked with Gut Health

Whole grains are a popular healthy choice, but between whole wheat and whole rye, does it matter what you choose? Scientists put these grains to the test, randomly assigning 70 overweight but otherwise healthy, middle-aged adults to a 6-week diet replacing all of their grain foods with whole wheat, whole rye, or refined wheat. There were no significant differences between the whole wheat and whole rye groups. Despite seeing no significant changes to the composition of the gut microbiome, the refined wheat group saw a greater drop in fecal butyrate (compounds associated with better health). The whole grain groups were less likely to feel bloated and more likely to have regular stools, but also more likely to pass gas. The authors conclude that “whole-grain foods have the potential for maintaining or improving some subjective and functional markers of gut health compared to refined grain foods.”
Journal of Nutrition. 2017 Nov;147(11):2067-2075. (Vuholm S et al.)

High Glycemic Index Foods Linked with Bladder Cancer

Carbohydrates are the building blocks of a balanced diet, but not all carbs are created equal. To see how diet might relate to bladder cancer risk, researchers analyzed the diets of 578 adults with bladder cancer and 608 controls without bladder cancer. Those regularly eating high glycemic index and glycemic load foods (foods that are more rapidly absorbed into the bloodstream, thus spiking your blood sugar) were more likely to have bladder cancer, as were those who regularly ate refined grains like bread and pasta. However, these results were not as strong in people who regularly eat vegetables. People who regularly eat whole grains and/or legumes tended to be less likely to have bladder cancer, but the results were not statistically significant.
British Journal of Nutrition. 2017 Nov;118(9):722-729. (Augustin LSA et al.)

Dry Whole Wheat Pasta at Lower Temperatures for Higher Quality

Given the growing interest in whole grain pasta, researchers wonder how different processing techniques can impact the quality of the product. In this study, researchers analyzed 20 samples of whole wheat spaghetti sold in Italy for cooking behavior, markers of heat damage and protein structure, as well as taste and aroma (using an electronic nose and tongue model for a more objective measurement). They found that whole wheat pasta produced using a low or medium temperature drying cycle (rather than high temperature) has less heat damage, is more likely to taste of umami (savory), and is less likely to taste bitter. The researchers also note that the amount of protein in the pasta sample had virtually no impact on the measures of quality tested, indicating that the drying process plays a much bigger role in preserving quality.
Journal of Food Science. 2017 Nov;82(11):2583-2590. (Marti A et al.)

Heart-Healthy, Traditional Mediterranean Diets Can Work Anywhere if Properly Followed

The Mediterranean Diet gets lots of buzz, but do you know what it really means to eat like a Mediterranean? In a meta-analysis of 27 studies, researchers estimate that every 2-point increase in Mediterranean Diet Score (0-9 scale) is related to an 11% lower risk of heart disease. Additionally, the researchers also analyzed the consistency between Mediterranean Diet Scores in different studies, and clarified the importance of using a standard definition of a Mediterranean diet, which emphasizes “vegetables, fruits, nuts, legumes, and mainly unrefined, minimally processed cereals; an abundant fat intake from virgin olive oil… a moderate consumption of fish and shellfish, a low consumption of meat… the consumption of wine during meals… and fermented dairy products.” In order to successfully transfer Mediterranean diets outside of the Mediterranean, the researchers also note the importance of following the Mediterranean Diet eating patterns (such as drinking a moderate amount of wine with meals throughout the week, rather than binge drinking on weekends) and choosing traditional foods (such as olive oil and beans) rather than untraditional foods (such as margarine and tofu).
Nutrients. 2017 Nov 8;9(11). (Martinez-Gonalez et al.)

Whole Grains Linked with Weight Loss, Less Inflammation

Why worry about calorie counting when whole grains can keep you satiated and help you lose weight? Researchers randomly assigned 50 Danish adults to a whole grain or refined grain diet for 8 weeks each, with a 6-week washout period in between. All of the participants were overweight, obese or had large waist sizes, and also had slightly high levels of blood sugar, cholesterol, or blood pressure before the study. The participants lost significantly more weight on the whole grain diet (- 0.4 pounds) compared to the refined grain diet (+ 2 pounds). This is likely because people naturally ate fewer calories on the whole grain diet, as whole grains are more satiating. Additionally, the whole grain diet (especially rye foods) significantly lowered inflammation (measured by IL-6 and CRP). However, the researchers noted no significant changes in insulin sensitivity (an indicator of how well your body is able to manage blood sugar), or the gut microbiome over the 8-week study.
Gut. 2017 Nov 1. pii: gutjnl-2017-314786. [Epub ahead of print.] (Roager HM et al.)  

Gluten Not Directly Responsible for Symptoms of Non-Celiac Gluten Sensitivity

Interest in a gluten-free diet has grown tremendously over the past decade. However, new research raises questions about whether gluten is a culprit of intestinal distress. In this study, researchers at the University of Oslo tested reactions to fructan (a compound found naturally in wheat and vegetables like onions, asparagus, and garlic) and gluten (a protein found naturally in wheat, barley, and rye). In a highly-controlled study of 59 people following a self-reported gluten-free diet, researchers tested patients’ symptoms after exposure to gluten, fructan, and a placebo.  Interestingly, 13 participants had significant symptoms after eating gluten, 24 had symptoms after eating fructan, and 22 had symptoms after eating a placebo, a food without gluten or fructan. There was no difference in GI symptoms after the gluten or placebo and more patients had reactions to the fructan as opposed to the gluten. The authors conclude that their findings weaken the use of the term “Non-Celiac Gluten Sensitivity,” and raise “doubts about the need for a gluten-free diet in such patients.
Gastroenterology. 2017 Nov 1. pii: S0016-5085(17)36302-3. (Skodje GI et al.)

Mediterranean Diet Linked with Lower Risk of Colorectal Cancer

While the healthfulness of the Mediterranean Diet has been recognized for decades, new studies continually build on evidence supporting the benefits of this nutritious and delicious diet. Researchers analyzed the eating patterns and DNA of 1,087 people with colon cancer and 2,409 people without colon cancer, to see how diet might relate to cancer risk. They found that closely following a Mediterranean Diet was independently linked with significantly lower risk of colorectal cancer, and that certain genes might also be protective. When looking at specific foods, vegetables and legumes, in particular, were linked with a significantly lower colorectal cancer risk. 
BMC Medical Genetics. 2017 Oct 30;18(1):122. (Alonso-Molero J et al.)

Mediterranean Diet During Pregnancy Reduces Incidence of Gestational Diabetes, Premature Birth

Expectant mothers have a unique opportunity to nurture their growing babies with a healthy diet, and some food choices can be especially beneficial. In a study of 874 healthy pregnant women in Spain, researchers randomly assigned half to a Mediterranean Diet (with olive oil and pistachios) and half to a similar healthy diet (but were told to avoid olive oil, nuts and other fat sources) early in their pregnancy (at 8-12 weeks). Those in the Mediterranean Diet group were 25% less likely to develop gestational diabetes (diabetes during pregnancy) than those in the low-fat group, and had significantly lower rates of premature deliveries and emergency C-sections. 
PLoS One. 2017 Oct 19;12(10):e0185873. (Assaf-Balut C et al.)

Culturally Relevant Foods are Important in Nutrition Assistance Programs

As part of a nutrition assistance program, 277 Mexican-heritage households in California’s Central Valley were given fruit and vegetable vouchers to spend at supermarkets. Researchers analyzed which fruits and vegetables were purchased with the vouchers to look for patterns. Fruits tended to be the most popular subgroup, while dark green and red-orange vegetables were less popular. They also found that “many of the most frequently purchased items were of cultural significance (tomatillo, chayote, chili/jalapeno pepper, and Mexican squash).” The researchers conclude that “food assistance programs should continue to include culturally important foods and be aware of the cultural values of their participants.”
Journal of Community Health. 2017 Oct;42(5):942-948. (Hanbury MM et al.)

Demand for More Whole Grains in Senior Care 

Fiber is important for the elderly to help prevent constipation and improve quality of life, and yet many older adults are falling short on fiber. In this study, 681 dietitians working in long-term (elderly) care answered questionnaires exploring barriers to whole grain consumption for older adults. Overall, 89.5% of dietitians reported that they would like to serve more whole grains. Twenty seven percent of dietitians reported that cost was a barrier to serving whole grains in long term care, and yet 75% of dietitians report that their patients need fiber supplements, averaging upwards of $11-20 a month per patient. Given that whole grains are a natural source of fiber, whole grains may be able to offset some of the cost of fiber supplementation. Other factors influencing the decision to purchase whole grains included dietary needs (such as special considerations for kidney disease), existing food contracts, nutritional content, and acceptance by residents.
Journal of Nutrition in Gerontology and Geriatrics. 2017 Oct-Dec;36(4):178-188. (Coffman CA et al.)

Mediterranean Diet Linked with Lower Risk of Blocked Arteries

As a way of testing if people might have blocked arteries (atherosclerosis), doctors compare blood pressure readings between your arm and your ankle in a test called the ankle-brachial index (ABI). To see how eating a Mediterranean Diet relates to these results, researchers analyzed the eating patterns and ABI of 425 pre-menopausal, middle-aged women in Italy. Researchers estimated that those most closely following a Mediterranean Diet were 10% less likely to develop peripheral arterial disease compared with those not following a Mediterranean Diet.
Nutrition, Metabolism, and Cardiovascular Diseases.  2017 Oct 3. pii: S0939-4753(17)30226-0. (Mattoidi AV et al.)

Mediterranean Diet Linked with Better Psychological Resilience

Psychological resilience, which measures how people are able to cope with stressors and maintain an optimistic outlook, is an important characteristic for aging healthfully. To better understand the relationship between health and well-being, researchers analyzed the eating patterns and psychological resiliency scores of 10,812 adults in Southern Italy. Those most closely following a Mediterranean Diet were significantly more likely to have better psychological resilience than those eating more of a Western-style diet. However, high alcohol intake was linked with lower psychological resilience.
European Journal of Clinical Nutrition. 2017 Sep 27. [Epub ahead of print.] (Bonaccio M et al.)

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