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If You Really Want to Optimize Your Diet, Focus on Fiber
Fiber isn’t sexy, but it’s the key to health
It’s a puzzle that doctors have long struggled to solve: Inflammatory bowel disease, a gut condition that was once vanishingly rare, now affects roughly three million Americans. Between 1999 and 2015 alone, rates of inflammatory bowel disease (IBD) surged by 44% in the U.S., according to the Centers for Disease Control and Prevention. No one is quite sure why.
The term “inflammatory bowel disease” encompasses two conditions — Crohn’s disease and ulcerative colitis. Both are associated with improper and damaging inflammation of the gastrointestinal tract. “IBD is a relatively new disease,” says Dr. Gilaad Kaplan, a gastroenterologist and professor of medicine and the University of Calgary’s Cumming School of Medicine. “We didn’t really begin to see it until the 1800s, and it’s almost exclusive to industrialized countries.”
Kaplan says the causes of America’s escalating IBD rates are almost certainly multiple and may include the injudicious use of bacteria-slaying antibiotics, which can disrupt the function of the human GI tract and microbiome. But while the harms of antibiotic overuse are on a lot of people’s radars, Kaplan says another, less talked about issue may be contributing to IBD’s rise: American’s paltry fiber intakes.
While national nutrition guidelines advise men and women to consume between 22 and 34 grams of fiber a day, the average American only swallows about 15 grams.
“There are many cohort studies that have shown people who eat less fiber are at high risk for developing Crohn’s disease,” Kaplan says. One of the most robust of these studies was a 2013 report from researchers at Harvard Medical School that looked at diet and health data collected from roughly 170,000 women over a period of more than 26 years. It found that those women who landed in the top fifth of the population in terms of fiber intakes were 40% less likely to have been diagnosed with Crohn’s disease than women who landed in the bottom fifth.
“The average person is not even remotely aware of the importance of fiber.”
