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They’ll help you run faster and live longer.
Written by: Sabrina Grotewold
It may be common knowledge that the virtues of fiber extend beyond digestive regularity to include absorbing some artery-clogging cholesterol and fat, affecting blood sugar and protecting against certain cancers, but the stereotypical image of grandpa gumming prunes in an effort to maintain longevity might need an update.
A study published in February in the Archives of Internal Medicine found that participants with the highest dietary fiber intake consumed from whole grain sources had a 22 percent lower risk of dying from any cause than their low-fiber diet counterparts. The study tracked the habits of more than 500,000 people ages 50 to 71; the high-fiber group consumed a daily average of 29.4 grams of fiber for men and 25.8 for women, and the low-fiber group averaged 12.6 grams for men and 10.8 for women (U.S. dietary guidelines recommend that individuals consume 14 grams of fiber per 1,000 calories). During the nine-year course of the study, over 20,000 men and 11,000 women died. While high-fiber diets were linked with a lower risk of death from all causes, including infectious, respiratory and cardiovascular diseases, authors wrote that fiber from beans and vegetables showed a weak link to mortality, while fiber from fruit showed no link. “Fiber isolates probably do not provide the same benefits as intact, whole grains,” study authors wrote.
“We found that fiber from grains, but not from other sources, was related to lower risk of death,” study co-author Yikyung Park, ScD, of the National Cancer Institute in Rockville, Md., wrote in an e-mail response. “Whole grains are rich sources of fiber, but also good sources of vitamins, mineral, and other phytochemicals that may provide health benefits.”
While the researchers suggest that the anti-inflammatory properties of fiber could provide one explanation for the reductions in mortality, Park was quick to point out that additional studies are needed to replicate these findings.
The take-away message? The high-carb diet that allows runners and other endurance athletes to train and race at their peak just may be the ticket to longevity in life and sports—as long as a large portion of those carbs come from high-fiber, minimally processed whole grains.
Hearty, healthy whole grain recipes: