Eating Whole Grains Leads to Healthier Blood Pressure & Sugar
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Researchers found that middle- to older-aged adults who ate at least three servings of whole grains daily had smaller increases in waist size, blood pressure, and blood sugar levels over time compared to those who ate less than one-half serving per day.
In their study, researchers at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University examined how whole- and refined-grain intake over time impacted five risk factors of heart disease: Waist size, blood pressure, blood sugar, triglyceride, and HDL ("good") cholesterol.
Using data from the Framingham Heart Study Offspring Cohort, which began in the 1970s to assess long-term risk factors of heart disease, the new research examined health outcomes associated with whole- and refined-grain consumption over a median of 18 years in 3,100 participants.
The team compared changes in the five risk factors, over four-year intervals, across four categories of reported whole grain intake, ranging from less than a half serving per day to three or more servings per day. According to the Dietary Guidelines for Americans 2020-2025, the recommended amount of whole grains is three or more servings daily. An example of a serving is one slice of whole-grain bread, a half cup of rolled oats cereal, or a half cup of brown rice.
The results showed that for each four-year interval:
- Waist size increased by an average of over 1 inch in the low intake participants, versus about ½ inch in the high intake participants.
- Even after accounting for changes in waist size, average increases in blood sugar levels and systolic blood pressure were greater in low intake participants compared to high intake participants.
The researchers also studied the five risk factors across four categories of refined-grain intake, ranging from less than two servings per day to more than four servings per day. Lower refined-grain intake led to a lower average increase in waist size and a greater mean decline in triglyceride levels for each four-year period.
"Our findings suggest that eating whole-grain foods as part of a healthy diet delivers health benefits beyond just helping us lose or maintain weight as we age. In fact, these data suggest that people who eat more whole grains are better able to maintain their blood sugar and blood pressure over time. Managing these risk factors as we age may help to protect against heart disease," said senior author Nicola McKeown.
Lead author Caleigh Sawicki, commented, "There are several reasons that whole grains may work to help people maintain waist size and reduce increases in the other risk factors. The presence of dietary fiber in whole grains can have a satiating effect, and the magnesium, potassium, and antioxidants may contribute to lowering blood pressure. Soluble fiber in particular may have a beneficial effect on post-meal blood sugar spikes.”
The greatest contributor to whole-grain intake among participants was whole-wheat breads and ready-to-eat whole-grain breakfast cereals. The refined grains came mostly from pasta and white bread. The difference in health benefits between whole and refined grains may stem from the fact that whole grains are less processed than refined grains. Whole grains have a fiber-rich outer layer and an inner germ layer packed with B vitamins, antioxidants, and small amounts of healthy fats. Milling whole grains removes these nutrient-dense components, leaving only the starch-packed refined grain behind.
Now more than ever it is easier to switch to foods containing whole grains, thanks to manufacturer ability to incorporate them into an ever-expanding range of foods (beverages too!). Whenever you can, substitute whole grains for white rice or white bread. Look online for an abundance of easy-to-follow recipes using grains.
Sawicki CM, et al. “Whole- and Refined-Grain Consumption and Longitudinal Changes in Cardiometabolic Risk Factors in the Framingham Offspring Cohort.” The Journal of Nutrition, 2021;
Tweet: If food is white, it ain’t right--this is a mantra to guide healthy diet habits. Switching to whole grains instead of white, bleached flour and rice products will help promote healthy longevity. #healthygrains, #nutritiousgrains, #ancientgrains
Vitamin D Supplements May Reduce Depression Symptoms
An extensive meta-analysis suggests that vitamin D supplementation may alleviate depressive symptoms in adults with depression. Conducted by an international team of researchers, the meta-analysis included dozens of studies from around the world.
Vitamin D is believed to regulate central nervous system functions the disturbances of which have been associated with depression. In addition, cross-sectional studies have observed an association between depressive symptoms and vitamin D deficiency. However, previous meta-analyses on the effects of vitamin D supplementation on depression have been inconclusive. In a meta-analysis, results from several different studies are combined and analyzed statistically.
The new meta-analysis on the association of vitamin D supplementation with depression is the largest one published so far, including results from 41 studies from around the world. These studies have investigated the efficacy of vitamin D in alleviating depressive symptoms in adults by randomized placebo-controlled trials in different populations. The studies included those carried out in patients with depression, in the general population, and in people with various physical conditions. The results of the meta-analysis show that vitamin D supplementation is more effective than a placebo in alleviating depressive symptoms in people with depression. There were major differences in the vitamin D doses used, but typically the vitamin D supplement was 50-100 micrograms per day.
"These findings will encourage new, high-level clinical trials in patients with depression in order to shed more light on the possible role of vitamin D supplementation in the treatment of depression," he concluded.
The cold weather is catching up with us, and will be here very soon. As the amount of daylight diminishes, so too does our exposure to the sun rays that help us produce sufficient vitamin D, therefore, supplementation is critical not only for mental health and well-being, but for immunity and many other areas of health.