Written by Bridgit Kin-Charlton, M.S., Ed., C.P.T.
Fiber isn’t a new subject: our hunter-gatherer ancestors consumed a wide range of fiber-containing plants, and many historical figures have acknowledged and promoted fiber’s benefits. Over time, our understanding of the powerful role fiber plays in keeping the body healthy has developed significantly.
Various studies have demonstrated that a diet adequate in fiber is linked to a lower risk of disease. And yet, despite strong scientific evidence touting the advantages of fiber, most Americans consume less than the recommended amount and eat too many empty calories.
Although the call for more fiber is not new, the promotional campaign has undergone a face-lift. Originally referred to as “crude,” fiber has morphed into a fashionable food additive. Why the push to eat more of it? Fiber’s potential health benefits are prolific, ranging from decreased risk of cardiovascular disease and diabetes to weight maintenance and regular laxation.
Fiber and Heart Health
The evidence for fiber’s role in reducing the risk of coronary heart disease (CHD) is so strong that the overall recommended adequate intake (AI) for fiber is based on a level proven to protect against CHD. Research suggests that the heart health benefits that fiber provides are based on how it effectively interferes with cholesterol and bile acid absorption, consequently lowering total cholesterol and low-density lipoprotein (LDL, or ‘bad’) cholesterol. An alternative mode of action in fiber’s fight against heart disease may be its ability to delay absorption of fat and carbohydrate, which in turn leads to increased insulin sensitivity and decreased levels of triglycerides.
Fiber and Weight Loss
There’s no debating that fiber is filling, but is it filling enough to prevent overeating and weight gain? Current data suggest that dietary fiber (intakes of 20-27 g per day) and fiber from supplements (up to 20 g per day) may help with weight control. However, it should be noted that research findings on fiber’s influence on appetite, energy and food intake have been inconsistent, with results differing according to fiber type and whether the fiber occurs naturally in food sources or is consumed as a supplement.
Fiber and Diabetes
Many observational studies have found an association between eating high-fiber foods and reduced risk of Type 2 diabetes. Dietary fiber is thought to play a vital role in reducing overall risk by helping to normalize glucose response and by decreasing insulin concentration and overall insulin requirements. Higher intakes (13-16 g per day in one study and as much as 30-50 g per day in a different study) from whole-food sources—in particular, cereal fiber—have been consistently associated with lower risk of Type 2 diabetes and improved insulin sensitivity.
Fiber and Cancer Prevention
While much of the research linking dietary fiber to cancer prevention is limited or mixed, fiber-rich foods tend to be concentrated sources of cancer-fighting antioxidants, vitamins and minerals. In addition, dietary fiber improves gut transit time, effectively reducing the length of time toxic substances stay in contact with the bowel, which may protect against colon cancers.
—-
Manufactures can call…
a food a “good source of fiber” if it contains 10 percent of the recommended amount, and an “excellent source of fiber” if it contains 20 percent of the recommended amount.
Dietary fiber listed on food labels is…
technically total fiber; it includes both dietary fiber and functional fiber. While this information is readily available, Americans still fall well below the recommendations.
Adding fiber to your diet…
isn’t as hard as it may seem. It can be as easy as choosing nutrient-rich foods—legumes, whole grains and fresh and frozen fruits and vegetables—while avoiding nutrient-poor choices, such as soft drinks and processed foods.
Good Sources of Fiber: Beans & Peas, Nuts & Seeds, Whole Grains, Berries (seed-containing)