The dietary fiber from whole grains can significantly reduce the chances of heart disease, bowel cancer, and premature death in general, according to a large review of studies from the World Health Organization (WHO). The research will influence new WHO guidelines, and runs counter to popular low-carb diets that encourage minimizing carbohydrates, including from whole grains.
The review asserts that consuming over 30, or at least 25 grams of fiber each day is ideal, while most people in the world get less than 20. With the highest-fiber diets, researchers found a 15 to 30 percent reduction in deaths overall, as well as from heart disease, relative to diets with the lowest amount of fiber.
They found 13 fewer deaths overall, and six fewer heart-disease cases, for every 1,000 people who don’t consume a high-fiber diet.
Cases of heart disease, stroke, type 2 diabetes, and colorectal cancer were reduced 16 to 24 percent. Whole grains were even found to promote weight loss.
“The randomized controlled trials involving an increase in the intake of whole grains showed reduction in body weight and cholesterol,” according the study, published Thursday in The Lancet.
The researchers looked at 185 observational studies and 58 clinical trials.
Fiber comes from whole grains, but is also found in nuts, as well as pulses like beans and lentils.
The research was led by a team at the University of Otago in New Zealand, headed by Professor Jim Mann. Mann also led the WHO review that informed their guidance on minimizing sugar, which is a type of carbohydrate.
The surge in popularity of diets that minimize or eliminate carbohydrates stems in part from this research, which encouraged significantly reduced consumption of sugar, which is also a type of carbohydrate.
However, the new study suggests that those that minimize carbohydrates as a whole may be missing out on a wide range of benefits from a high-fiber diet.
“Here we have got very strong evidence that a high-fibre diet, which for the majority of people is at least high-ish in carbohydrates, has an enormous protective effect – a wide range of diseases including diabetes, cardiovascular disease and cancer benefit from a high-carbohydrate diet,” Mann said, speaking to The Guardian.
He also warned that with so much invested in low-carb diets, from both health professionals and others, even the landmark study and WHO guidelines may do little to immediately curtail the popularity of the low-carb approach:
“It’s twofold. There is the commercial vested interest, which there is an enormous amount of from chefs and celebrity chefs and so on. And there is also the professional vested interest.”