Don't ditch the bread just yet. A new study from the Harvard School of Public Health reveals that, counter to what low-carb enthusiasts would have you believe, eating whole grains improves health and may even help you live longer.
According to the study, each daily serving of whole grains reduced risk of death by 5 percent, topping out at about 9 percent for a whole grain-rich diet.
"This study further endorses the current dietary guidelines that promote whole grains as one of the major healthful foods for prevention of major chronic diseases,” Qi Sun, M.D., ScD, a senior author of the study said in a statement.
One component of whole grains, bran -- the hard, fibrous outer layer of cereal grain -- may play a particular role in reducing this harm: Researchers found that a diet rich in bran reduced overall death by 6 percent and reduced the risk of developing heart disease, which is the leading cause of death in the United States, by up to 20 percent. Germ, another component, didn't seem to improve mortality rates at all.
Sun and team used data from two famous long-term investigations, the Nurses' Health Study and the Health Professionals Follow-Up Study, to determine a whole grain-rich diet's role in longevity. The researchers looked at whole grain intake and mortality over a 25-year period, adjusting for things like overall diet (excluding grains), body mass index and smoking status to eliminate tertiary explanations.
Previous, well-established research has linked diets rich in whole grains to overall heart health and reduced risk of diabetes but hadn't looked specifically at longevity. The team also looked at deaths from cancer among the 74,000 women and 43,000 men who participated in the study, finding that whole grains played no role in cancer mortality, specifically.
A more targeted analysis found that swapping whole grains for red meat had a protective effect, reducing mortality by 20 percent -- 12 percentage points more than swapping whole grains for refined ones.
Something to keep in mind as your Paleo-loving friends eschew oatmeal for bacon.