Fiber whole grains death, protect against noncommunicable diseases.
Consuming high amounts of dietary fiber and whole grains was associated with reduced risk for noncommunicable diseases, such as coronary heart disease, type 2 diabetes and colorectal cancer, according to findings published in The Lancet.
“Previous reviews and meta-analyses have usually examined a single indicator of carbohydrate quality and a limited number of diseases so it has not been possible to establish which foods to recommend for protecting against a range of conditions,” Jim Mann, PhD, professor in human nutrition and medicine at the University of Otago, New Zealand, said in a press release.
Mann and colleagues performed a series of reviews and meta-analyses of 185 studies and 58 clinical trials to determine the association between carbohydrate quality and protection against noncommunicable diseases and weight gain and to inform recommendations for optimal daily fiber intake.
The included studies evaluated the association between carbohydrate quality and noncommunicable disease incidence, mortality and risk factors. Noncommunicable diseases studied included coronary heart disease, CVD, stroke, type 2 diabetes, colorectal cancer and cancers associated with obesity, such as breast, endometrial, esophageal and prostate cancer.
The researchers excluded studies that included patients an existing chronic disease, as well as weight loss trials or trials involving supplements.
Participants were categorized by daily dietary fiber intake (less than 15 g, 15-19 g, 20-24 g, 25-29 g, 30-34 g and 35-39 g of fiber per day).
Participants consuming the highest amount of dietary fiber demonstrated a 15% to 30% reduction in all-cause and cardiovascular-related mortality. Consuming higher intakes of dietary fiber also reduced the incidence of coronary heart disease, stroke, type 2 diabetes and colorectal cancer by 16% to 24%.
Body weight, systolic BP and total cholesterol were lower in participants with higher intakes than lower intakes of dietary fiber.
Increasing dietary fiber intake by 8 g per day reduced total deaths and incidences of coronary heart disease, type 2 diabetes and colorectal cancer by 5% to 27%. This also increased protection against stroke and breast cancer.
Consuming between 25 g and 29 g of dietary fiber per day generated the greatest risk reduction for CVD, type 2 diabetes and colorectal and breast cancer.
Increasing consumption of whole grains by 15 g per day reduced total deaths and incidences of coronary heart disease, type 2 diabetes and colorectal cancer by 2% to 19%. The risk for noncommunicable diseases were reduced by 13% to 33% with higher intakes of whole grains. Consuming whole grains also promoted weight loss.
Diets with a low glycemic index and load protected against type 2 diabetes and stroke only.
“Our findings provide convincing evidence for nutrition guidelines to focus on increasing dietary fiber and replacing refined grains with whole grains,” Reynolds said. “This reduces incidence risk and mortality from a broad range of important diseases.”