Whole Grains 101

whole grains 101

Health Studies on Whole Grains

Whole grain bread is healthy.

Every day, more and more studies show the benefits of whole grains. We regularly post new studies here, where you can browse through them at random. Or, you can use our filters to hone in on a specific question, such as "Does barley reduce the risk of diabetes?" or "What's the research about whole grains and hypertension?"

Filter the studies below by selecting a grain and/or a disease/condition, then click apply.


Americans ate 79% more Whole Grains from 1999-2012, & Improved Overall Diet

Slowly but surely, Americans seem to be making progress on the journey toward healthy eating. Using survey (NHANES) data from 33,932 Americans, researchers analyzed how U.S. eating patterns have changed from 1999-2012. Overall, U.S. diets improved by 11.6% on the American Heart Association primary diet score, and by 9.7% on the American Heart Association secondary diet score. One of the biggest dietary improvements was the 79% increase in whole grain consumption (which increased from 0.56 to 1.0 servings per day). Much of this is driven by the increase in whole grain breads (up by 0.24 servings per day) and other whole grain foods, like pasta and crackers (up by 0.11 servings per day). Other improvements included the increase in nuts or seeds (up 0.25 servings per day), increase in whole fruit (up 0.15 servings per day), and decrease in sugar-sweetened beverages (down 0.49 servings per day) and 100% fruit juice (down 0.11 servings per day). There were no significant changes in the amount of total fruits and vegetables, processed meat, saturated fat, or sodium eaten. Despite these improvements, researchers note disparities by race and income level, with greater improvements seen in non-Hispanic white adults, and those with more money.
JAMA. 2016 Jun 21;315(23):2542-53. (Rehm CD et al.)

Whole Grains Linked with Longevity

In a meta analysis, Harvard scientists analyzed the whole grain intake and rates of death for 786,076 adults across 14 studies. Compared to people who ate the least whole grains, people who ate the most whole grains had a 16% lower risk of death from all causes, an 18% lower risk of death from heart disease, and a 12% lower risk of death from cancer. However, the significantly lower risk of cancer death was only seen in people who ate at least 30g whole grains per day (the amount in about ½ cup cooked brown rice, or 2 slices of 100% whole grain bread). The researchers also observed a dose response relationship, meaning the more whole grains someone ate, the less likely they were to die during the study period. According to the scientists, these results “strongly supported the current Dietary Guidelines for Americans,” which encourage at least 3 servings of whole grains per day (totaling at least 48g whole grains).
Circulation. 2016 Jun 14;133(24):2370-80. (Zong G et al.) 

Whole Grains Linked with Lower Risk of Heart Disease, Cancer, Respiratory Disease, Infectious Diseases, Diabetes, and Early Death

Researchers in Europe and the US analyzed 45 studies (ranging from 245,012 to 705,253 participants each) in a meta analysis to understand the relationship between whole grains and health. Compared to people who ate the least whole grains, people who ate the most whole grains had a 16-21% lower risk of heart disease, an 11% lower risk of cancer, and an 18% lower risk of death from all causes, as well as a 19% lower risk of death from respiratory disease, a 36% lower risk of death from diabetes, a 20% lower risk of death from infectious disease, and a 21% lower risk of death from all non-cardiovascular, non-cancer causes. The researchers also found that a 90g increase in whole grain foods per day (about 3 servings) was linked with a 19-22% lower risk of heart disease, a 15% lower risk of cancer, and a 17% lower risk of death from all causes, and that “even moderate increases in whole grain intake could reduce the risk of premature mortality.” Whole grain bread, whole grain cereals, total grains, total cereals, total bread, pasta, and bran, were also singled out for their relationship with lower rates of various diseases and/or early death. The researchers conclude that their findings “strongly support existing dietary recommendations to increase whole grain consumption in the general population.”
British Medical Journal. 2016 June 14;353. (Aune D et al.)


Whole Grains May Help Prevent Early Death

Yet another study adds to the growing body of evidence that whole grains may help prevent early death. Using data from the U.S., Europe, and China, Chinese researchers analyzed data from 33 large studies (analyzing hundreds of thousands of people for up to 26 years) to examine the relationship between eating whole grains and prevention of early death. They found that eating 50g whole grains per day (the amount in about 3 servings of whole grains) was linked with a 22% lower risk of death from all causes, a 30% lower risk of death from heart disease, and an 18% lower risk of death from cancer throughout the study period. The scientists also observed a 32% lower risk of death from ischemic heart disease (heart problems caused by narrowed arteries) in whole grain eaters, but did not find a significantly lower risk of death from stroke.
American Journal of Clinical Nutrition. 2016 May 25. pii: ajcn122432. [Epub ahead of print] (Chen GC et al.)

Whole Grains May Help Prevent Heart Attacks

Researchers analyzed the diet of nearly 55,000 Danish adults and then tracked their health outcomes for over 13 years. Those consuming the most whole grains per day had a 25-27% lower risk of having a heart attack than those eating the least amount of whole grains per day. In fact, increasing whole grain intake by 25g per day was linked with a 12-13% lower risk of a heart attack. Among the different types of whole grains, rye and oats appeared to be especially protective.
American Journal of Clinical Nutrition. 2016 Feb 17. Pii:acjn124271. (Helnæs A et al.)

Healthy Diet with Whole Grains, Fruits, Vegetables May Protect Against Cognitive Decline

Since there is no known cure for cognitive decline, prevention and deceleration of this condition are an important area of research. Most people’s diets change from time to time, so researchers wanted to study how these changes affect cognition. In a study of over 2000 Swedish older adults at least 60 years old, eating a “Western diet” (lots of refined or processed foods, red meats, high fat dairy products, saturated/trans fats, and sugar) was associated with more cognitive decline, whereas eating a more “prudent” diet (a healthy diet with lots of fruits, vegetables, whole grains, rice/pasta, legumes, nuts, fish, and low-fat dairy products) was associated with a deceleration of cognitive decline. However, the most fascinating finding is that every little bit helps. More frequent intake of foods from the "prudent" diet might weaken the negative cognitive effects associated with the Western diet, even if you're unable to change all your habits.
Alzheimers and Dementia. 2016 Feb;12(2):100-9. (Shakersain B, et al.)

Less Plate Waste with Brown Rice at Chinese Restaurants, But Many Factors Influence Decision to Serve it

Minnesota researchers interviewed managers and owners of 30 Chinese restaurants in the Twin Cities area in 2013 (14 with brown rice, 16 without) to learn about the benefits and challenges of serving brown rice. Of the restaurants serving brown rice, 40% served it because of customer requests. However, 80% of restaurants not serving brown rice believed that low customer request was the biggest constraint, estimating that at least 100 customers per week would have to order it to justify putting it on their menus. Regarding cost, 2 of the 14 restaurants reported higher profits for brown rice (mostly due to higher sales), and 6 of the restaurants reported the same profits for brown and white rice. Additionally, 3 of the 14 restaurants reported selling more brown rice than white rice, while another 4 restaurants had moderate brown rice sales (10-50%).The researchers also conducted a plate waste study at one of the Chinese restaurants in 2013, to see how much white rice and brown rice got thrown away by customers. After observing 353 customers of various ages (200 chose brown fried rice, 153 chose white fried rice), they found that brown rice eaters wasted significantly less of their rice (15.1%) than white rice eaters (20.9%).
Journal of Foodservice Business Research. 2016 Feb 3;19(1):77-88. (Liu T et al.)

Eating Fiber in Young Adulthood Linked with Lower Breast Cancer Risk

Dietary fiber is an important nutrient found in plant foods (mostly in whole grains, fruits, vegetables, and pulses). To study the link between fiber intake and breast cancer risk, Harvard scientists analyzed the adolescent and early adulthood diets of over 90,000 women, and noted any diagnosis of breast cancer. The researchers found that every 10g of fiber in adolescence and young adulthood was linked with a 14% and 13% lower risk of breast cancer, respectively. In fact, those eating the most fiber in adolescence and young adulthood (25g per day) were 25% less likely to get breast cancer than those eating the least fiber (12g per day).
Pediatrics. 2016 Feb 1. pii: peds.2015-1226. (Farvid MS et al).

Whole Grains Linked with Less Inflammation and Slower Cognitive Decline in Aging

A “grain brain” seems to be a healthy defense against inflammation and accelerated cognitive decline. In a British study, researchers analyzed the diets, inflammation markers, and cognitive health of over 5,000 middle aged adults over six years. The scientists found that those eating diets high in red and processed meat, peas, legumes (mostly baked beans) and fried food, and lower in whole grains, were more likely to have higher levels of inflammation and accelerated cognitive decline. In fact, whole grains had the strongest link to anti-inflammatory markers among all 37 food groups studied.
Clinical Nutrition. 2016 Jan 29. Pii: S0261-5614(16)00035-2. (Ozawa M et al.)

US Whole Grain Intake Improves from 2001-2012, Linked with Better Weight

We know that healthy whole grains are growing in popularity, but new data quantify this trend. Minnesota researchers analyzed the whole grain intake and BMI, waist circumference, and obesity of nearly 45,000 children and adults from 2001 to 2012. The scientists found that while less than 1% of kids and 8% of adults met whole grain recommendations (about 3 oz equivalents per day), whole grain consumption has improved in both groups (adults from 0.72 oz equivalents in 2001 to 0.97 in 2012, kids from 0.56 oz equivalents in 2001 to 0.74 in 2012). The biggest source of whole grains for both kids and adults alike were yeast breads and ready to eat cereals. Those eating the most whole grains had a lower BMI and waist circumference, and were less likely to be overweight or obese. The researchers conclude that “greater whole grain consumption is associated with better intakes of nutrients and healthier body weight in children and adults,” and that “Continued efforts to promote increased intake of whole grain foods are warranted.”
Nutrition Journal. 2016 Jan 22;15(1):8. (Albertson AM et al.)

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