Whole grains

When it comes to reducing your risk of type 2 diabetes, a diet with healthy carbohydrates should be a key part of your nutrition playbook. In this review, researchers analyzed 67 studies related to food groups and risk of type 2 diabetes, metabolic syndrome, and diabetes mortality. A high intake of whole grains was linked with a significantly lower risk of type 2 diabetes, with similar (though no quite as strong) tendencies for fruit and vegetable intake. A high intake of red meat, processed meat, and/or sugar sweetened beverages were all linked with a higher risk of type 2 diabetes. For other food groups, the risk of type 2 diabetes wasn’t statistically significant in either direction.
J Nutr. 2025 Mar 21:S0022-3166(25)00173-7. doi: 10.1016/j.tjnut.2025.03.021. (Banjarnahor RL et al.)

Just because someone says they don’t like whole grains, doesn’t mean we should write off their interest immediately. In fact, changing the food environment by simply exposing these people to whole grains is enough to change their attitudes, a new study shows. In this study, researchers provided 45 healthy adults with either refined grain or whole grain products to take home for six weeks. Researchers measured how much of the provided grain foods were eaten, and they measured if people associated different types of grains with either an unpleasant or pleasant taste before and after the study using an implicit association computer test with measured response times. The whole grain group consumed just as much of their provided grains as the refined grains group, and individuals who considered whole grains as unpleasant tasting before the study were significantly more likely to change their tune and consider whole grains to be pleasant tasting after being provided with the whole grain foods.
Front Nutr. 2024 Sep 30:11:1408256. doi: 10.3389/fnut.2024.1408256. eCollection 2024. (De Leon A et al.)

Poor diet can be a risk factor for certain types of liver diseases, so researchers conducted a meta-analysis of studies to see how whole grain intake might relate to liver disease risk. Those eating the most whole grains had a 10% lower risk of developing any chronic liver disease than those eating the least. The results were especially pronounced for a certain subgroup of serious liver diseases. Eating whole grains was linked with a 35% lower risk of developing cirrhosis (a potentially fatal form of liver damage) and a 63% lower risk of chronic liver disease mortality.
Food Funct. 2024 Sep 30;15(19):9707-9717. doi: 10.1039/d4fo03077j. (Zhang Y et al.)

Early-onset (diagnosed before age 50) colorectal cancer risk is thought to be influenced by diet and lifestyle factors, so researchers wanted to find out which foods might be involved with colorectal cancer risk. Using data from the Global Burden of Disease Study 2019, scientists found that a diet low in whole grains is one of the leading dietary risk factors for early onset colorectal cancer, ahead of diets high in red and processed meat and even diets low in fiber. 
Frontiers in Nutrition. 2024 May 31:11:1384352. doi: 10.3389/fnut.2024.1384352. eCollection 2024. (Su J et al.)

Whole grains have long been linked with longevity and are a central part of the diet of many of the world’s longest-lived people. New research, however, suggests that whole grains don’t just add years to life – they may also add life to years, by being linked with a longer healthspan, or the length of time that a person is healthy, not just alive. In this study of more than 48,000 Danish adults, men who ate the most whole grains in midlife lived roughly one year longer without disease compared with men who ate the least whole grains. The authors concluded that “intake of whole grains in mid-life was associated with healthy aging looking 20 years ahead.”
Eur J Nutr. 2024 Mar 7. doi: 10.1007/s00394-024-03357-3. Online ahead of print. (Eriksen AK et al.)

Good nutrition can help support brain health and healthy aging, and it’s increasingly clear that whole grains are an important part of the equation. In a study of 3,326 older adults (average age 75), those eating three or more servings of whole grains per day had a slower rate of decline in global cognition, perceptual speed, and episodic memory compared to those who ate fewer than one serving per day. These results were statistically significant for the group as a whole and for African American participants (who made up 60% of the study population), but did not quite reach statistical significance for white participants (who made up a smaller proportion of the study population).
Neurology. 2023 Nov 22:10.1212/WNL.0000000000207938. doi: 10.1212/WNL.0000000000207938. (Liu X et al.)

Carbohydrate foods from different sources have different impacts on the body, meaning that it is important to choose quality carbohydrates like whole grains. In this study, researchers analyzed the eating patterns and weight changes of 136,432 adults for more than 2 decades. Eating more whole grains, fruit, and non starchy vegetables was linked with a lower risk of weight gain, while eating more refined grains and starchy vegetables (peas, corn, potatoes) was linked with a higher risk of weight gain.
BMJ. 2023 Sep 27:382:e073939. doi: 10.1136/bmj-2022-073939. (Wan Y et al.)

Whole grain’s protective effect against heart disease and diabetes is well-documented, and because these chronic conditions also relate to risk of brain health and mental health, researchers wanted to examine this relationship directly. In this study, scientists analyzed 23 studies on whole grain intake and risk of cognitive decline, depression, anxiety, and mood disorders and evaluated the strength of the evidence. They found that people who eat more whole grains are more likely to have better mood, depression, and anxiety scores. The evidence on whole grains and cognition was inconclusive, meaning that more research is needed.
Adv Nutr. 2023 Apr 19;S2161-8313(23)00288-0. doi: 10.1016/j.advnut.2023.04.003. (Ross AB et al.)

Type 2 diabetes is one of the most prevalent chronic diseases around the world, impacting millions of people. In this study, researchers developed risk-assessment models to estimate how much various dietary habits contribute to type 2 diabetes risk in 184 countries around the world. The largest burden (26.1%) of type 2 diabetes was attributed to low whole grain intake. Other factors contributing to high type 2 diabetes burden included high intake of refined rice and wheat (24.6%) and high intake of processed meat (20.3%).
Nat Med. 2023 Apr;29(4):982-995. doi: 10.1038/s41591-023-02278-8. Epub 2023 Apr 17. (O’Hearn M et al.)

Brain-healthy diets include a variety of healthy ingredients, and researchers wonder if whole grains specifically might be related to dementia risk. In a study of 2,958 adults in the U.S., those eating the most whole grains were 28% less likely to develop all-cause dementia and were 36% less likely to develop Alzheimer’s dementia over the 12-year study period. The researchers note that more research is needed to better understand this relationship.
J Prev Alzheimers Dis. 2023;10(1):133-136. doi: 10.14283/jpad.2022.91. (J Wang et al.)