SEARCH HEALTH STUDIES

Search Results

Switching to Whole Grains Can Reduce Abdominal Fat

Visceral fat is a dangerous type of abdominal fat that can surround vital organs like the liver. To see if grain choices might play a role in this fat distribution, researchers randomly assigned 50 Japanese men with a BMI of 23 or greater (midway through the “healthy weight” range or heavier) to a diet with whole grain bread or white bread for 12 weeks, and had their visceral fat estimated using tomography scans. After the 12-week study, the whole grain group lost 4 cm of visceral fat around their middle, while the white bread group showed no significant changes.
Plant Foods and Human Nutrition. 2018 Apr 18. [Epub ahead of print.] (Kikuchi Y 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.)

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.)

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.)

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 Gallbladder Removal

Cholecystectomy, or the removal of the gallbladder, is a common treatment for gallstones, which affect 10-15% of the adult population. Some studies suggest that foods typical of the Western diet (high in calories, cholesterol, etc.) may increase the risk of gallstone disease. Researchers analyzed whether a healthful diet, like the Mediterranean diet, could potentially prevent cholecystectomy in a group of 64,052 French women. They found that those more closely following the Mediterranean diet had a lower risk of cholecystectomy. Specifically, a higher intake of legumes, fruit, vegetable oil, and whole grain bread was associated with a lower cholecystectomy risk, and a higher intake of ham was associated with a higher risk.
American Journal of Gastroenterology. 25 July 2017. [Epub ahead of print.] (Barré A 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.)

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.)

Whole Grains, Pasta Linked with Lower Breast Cancer Risk

An estimated 1 in 8 women in the US will develop invasive breast cancer over her lifetime, so preventive lifestyle choices are an important area of research. To see how diet plays a role, Harvard scientists analyzed the grain food choices of 90,516 pre-menopausal women, and monitored their health outcomes for 22 years. After adjusting for known breast cancer risk factors, those eating 1.5 servings of whole grains per day were 18% less likely to get pre-menopausal breast cancer than those eating hardly any whole grains (0.2 servings/day). This relationship was no longer significant after adjusting for fiber, suggesting that the fiber in whole grains may play a protective role. When looking at individual grain foods, brown rice and pasta (white or whole grain) were associated with a lower risk of overall breast cancer risk, while white bread was linked with a higher risk of overall breast cancer.
Breast Cancer Research and Treatment. 2016 Sep;159(2):335-45. (Farvid MS et al.)

Whole Grains May Prevent Early Death

Whole grains (like rye, oats, and whole wheat) have a strong history in traditional Scandinavian cuisine, but as in other regions, the food landscape is changing and refined grains have replaced some traditional foods. To see how eating whole grains relates to mortality, researchers analyzed the diets of over 120,000 people in Denmark, Norway, and Sweden.  The scientists found that those who ate the most whole grains had significantly lower risk of death from all causes. When analyzing individual whole grains, the researchers found significantly lower mortality rates in those who ate the most whole grain breakfast cereals, whole grain bread, oats, rye (only statistically significant for men), and whole wheat. These findings support existing evidence that whole grains may contribute to longevity.
British Journal of Nutrition. 2015 July 23:1-16. (Johnsen NF et al.) [Epub ahead of print]

Whole Wheat Can Improve Inflammation and Influence Gut Bacteria

Researchers are increasingly turning to gut bacteria to learn more about complex conditions such as inflammation. To study this relationship, scientists randomized 63 overweight and obese adults to a diet containing either whole grains (in the form of shredded wheat) or refined grains (in the form of white bread and crackers) for 4-8 weeks. In addition to decreased inflammation in the whole grain group (a good thing!), the scientists found that one of the most abundant beneficial plant compounds (ferulic acid) from whole wheat is released and absorbed in the gut, where it is likely metabolized. In line with other studies on how whole grains improve gut health and diversity, the researchers also found that whole-wheat consumption positively influenced bacterial communities in the study participants.
American Journal of Clinical Nutrition. 2015 Feb;101(2):251-61. (Vitaglione P et al.)

Antioxidants in Whole Wheat Unaffected During Baking

Whole grains are starting to gain recognition as being rich sources of antioxidants, but many wonder if these antioxidants are affected during processing, such as bread baking. To test this theory, scientists at the University of Maryland measured phenolic acid (antioxidant) content in flour, dough, and bread fractions from three whole and refined wheat varieties. As expected, “all phenolic acids measured were more abundant in whole wheat than refined samples.” The researchers also found no significant change in antioxidant levels after the breads were baked. “Thus, the potential phytochemical health benefits of total phenolic acids appear to be preserved during bread baking.”
Journal of Agricultural and Food Chemistry. 2014 Oct 20 [Epub ahead of print] (Lu Y et al.)

Pages