Everyone has heard “you need more fiber”, but what does that mean? More boxed cereals? More bran? And, How much is enough? And why does everyone tell us to ‘take more fiber’?
Let’s first look at what dietary fiber (aka: roughage) is? It is the indigestible portion of food from plants.
There are two main components: Soluble fiber, which dissolves in water and delays gastric emptying which in turn, can cause an extended feeling of fullness and; insoluble fiber, which does not dissolve in water and provides bulking. Bulking fibers absorb water as they move through the digestive system, easing elimination of toxic waste through the colon.
Dairy and white flour products are low in fiber as opposed to cereal grains, seeds and fruits which are high in fiber. Dietary fiber is, in fact, found in all fruits and vegetables, pulses / legumes / seeds (such as lentils, ground flax seeds, chickpeas, beans, etc) and whole grains (oats, oat bran, oat meal, whole-wheat etc).
The Functions of Fiber
Eating a fiber rich diet has many health benefits and according to the University of Maryland Medical Centre, the consumption of soluble fiber has been shown to protect against heart disease by reducing cholesterol levels. There are studies which have focused on soluble fibers such as oats, psyllium, pectin, and guar gum and reviews suggested that these fibers reduce cholesterol, especially the ‘bad’ cholesterol, LDL. (see link below of study in American Journal of Clinical Nutrition)
Soluble fiber aids in regulating sugar intake and this is especially useful for people with diabetes and metabolic syndrome.
Consumption of insoluble fiber may also reduce the risk of constipation! By improving bowel function, dietary fiber can reduce the risk of digestive diseases such as diverticulitis or haemorrhoids and may have a protective effect on colon cancer. As it is fermented by gut bacteria, it improves immune-, digestive- and overall health.
As with most things “nutrition”, depending on your source determines your recommended daily amount required but the average requirement for women is around 25g and for men 38g. Ideally we count “fiber” as a total and don’t necessarily discriminate between soluble and insoluble fiber.
Most foods high in fiber are also generally healthy for other reasons. For example fruit, vegetables, legumes and whole grains are not only high in fiber but also in vitamins and other essential nutrients.
Therefore a diet high in fresh fruit, vegetables, legumes and whole-grains is a high fiber diet which is considered a healthy diet!
Let’s not forget the weight loss properties of fiber as it simply helps you feel full without adding a lot of extra calories to your diet.
Lowering arthritis: http://www.pcrm.org/health/medNews/high-fiber-diet-lowers-risk-for-arthritis
Lowering cholesterol: http://ajcn.nutrition.org/content/69/1/30.full