Whole grains are rich in dietary fiber, vitamins, and minerals. Robust evidence indicates that people who consume whole grains as part of a healthy diet are less likely to develop cancer or cardiovascular disease or die prematurely. However, findings from a recent study suggest that consumption of refined grains increases a person’s risk of cardiovascular disease and premature death.
Refined grains are processed to remove the bran and germ, imparting a finer texture to the grains and extending their shelf life. The refining process also removes many vitamins, minerals, and dietary fiber. Examples of refined grains include white flour and white rice. Refined grains are used to make many processed foods, such as white bread, breakfast cereals and pastries, and baked desserts. Evidence suggests that refined grain consumption is linked with higher levels of atherogenic small, dense LDL particles](https://jamanetwork.com/journals/jama/article-abstract/185711).
The authors of the new study drew on data from a diverse population of more than 137,000 people living in 21 low, middle, and high income countries enrolled in the Prospective Urban and Rural Epidemiology study. Participants completed questionnaires about their socioeconomic status, health, physical activity, and diet.
Analysis of the questionnaires revealed that eating 350 grams or more (about seven servings) of refined grain products per day, such as white bread, noodles, breakfast cereals, crackers, and bakery products, increased a person’s risk of stroke by 47 percent, cardiovascular disease by 33 percent, and premature death by 27 percent. Eating whole grains and rice did not increase risk.
These findings suggest that consumption of refined grains increases a person’s risk of cardiovascular disease and premature death. However, this was an observational study and did not establish causation. The data were adjusted to account for several possible confounding factors such as body composition, physical activity, and socioeconomic status, but other factors could be at play.
The science digest is a special email we send out just twice per month to members of our premium community. It covers in-depth science on familiar FoundMyFitness related topics.
If you're interested in trying out a few issues for free, enter your email below or click here to learn more about the benefits of premium membership here.