We should all be eating more dietary fiber to improve our health - that's the message from a health review by scientists in India. The team has looked at research conducted into dietary fiber during the last few decades across the globe and now suggests that to avoid initial problems, such as intestinal gas and loose stool, it is best to increase intake gradually and to spread high-fiber foods out throughout the day, at meals and snacks. Writing in the International Journal of Food Safety, Nutrition and Public Health, the team offers fruit, vegetables, whole-grain foods, such as muesli and porridge, beans and pulses, as readily available foods rich in dietary fiber.
Dietary fiber, also known as roughage, is the general term of the non-digestible parts of the fruit and vegetable products we eat. There are two forms soluble and insoluble. Soluble (prebiotic, viscous) fiber that is readily broken down or fermented in the colon into physiologically active byproducts and gases. The second form is insoluble fiber, which is metabolically inert, but absorbs water as it passes through the digestive system, providing bulk for the intestinal muscles to work against and easing defecation.
Vikas Rana of the Rain Forest Research Institute, in Assam, India, and colleagues point out that research has shown that modern food habits have, it seems, led to an increase in the incidence of obesity, cardiovascular diseases, and type 2 diabetes. These are growing more common even in developing nations where a "western" diet of highly processed foods, high in sugars and saturated fats, beef and dairy products and low in dietary fiber is displacing more traditional options. The team suggests that evidence points to a loss of dietary fiber in the diet as being a major risk factor for health problems but one of the simplest to remedy without recourse to major changes in diet or the addition of supplements or so-called functional foods and nutraceuticals to the diet.
Given that dietary fiber has physiological actions such as reducing cholesterol and attenuating blood glucose, maintaining gastrointestinal health, and positively affecting calcium bioavailability and immune function, it is important for the current generation and future generations that this component of our diets be reasserted through education and information.
"Consuming adequate quantities of DF can lead to improvements in gastrointestinal health, and reduction in susceptibility to diseases such as diverticular disease, heart disease, colon cancer, and diabetes. Increased consumption has also been associated with increased satiety and weight loss," the team concludes. Given the ready availability particularly in the West and in the relatively richer parts of the developing world of vegetables, fruit and other foods high in dietary fiber it is a matter of recommending that people eat more dietary fiber rather than consistently taking the unhealthy low-fiber option throughout their lives.
"Dietary fiber and human health" in Int. J. Food Safety, Nutrition and Public Health, 2011, 4, 101-118