Fitness and Weight Loss

There is much talk about the fibers, almost became fashionable.
Nutrition as a science was developed mainly during the second half of this century and despite its constant evolution there is still confusion about what constitutes a healthy diet. The concept of including fiber in our diets actually took importance over the past twenty-five years. Before she was considered an inert element lacking in relevance, but experimental and epidemiological observations drastically changed this view. It is now accepted each day with greater emphasis than is possible to design diets that help prevent disease. Fiber is the part of plant foods that pass through the intestinal tract without being digested.
Why fibers are not digested in the intestinal tract of man?
Because the molecular structures of various fibers (hemicellulose, cellulose, pectins, mucilages, etc.) are unique and can not be digested by our digestive enzymes. The enzymes produced by salivary glands, pancreas and intestine have unfolded molecules as a function of protein, carbohydrates and fats and have specificity to act on certain structures. This fact that was never awarded importance was the subject of studies in the seventies in which fiber intake linked to cancer and cardiovascular disease and who achieved a great discovery to test the hypothesis that fiber plays a role very important in preventing cardiovascular disease and certain types of cancer. It has been shown that wheat bran is important for its function and laxative agent in preventing colon and breast cancers. While oat bran and psyllium prevent cardiovascular disease.

What are the types of dietary fiber?
There are two types of fiber: soluble fiber, which is viscous and forms a gel in water. It includes components such as pectins and mucilages found in beans, some fruits, oats, rye, etc.. The other is the insoluble fiber is mainly composed of cellulose, hemicellulose and lignin. Foods containing wheat bran and whole grains are good sources of this type of fiber. The two types have different functions, so it is important to make sure to include both in our diet.

What is the mechanism by which the insoluble fibers have the effect of accelerating and intestinal transit benefit?
Insoluble fibers have great capacity to absorb water so that they act like sponges. This increases the volume of stool, accelerates intestinal transit stimulating peristalsis, ie the coordinates of the musculature of the intestine and requires less pressure on the walls of the colon for expulsion.

Are there epidemiological observations confirm that populations with high fiber in their diets have lower incidence of constipation?
Certainly there is ample evidence of this. In Japan, where it handles the concept of functional foods, the Ministry of Health officially endorsed the promotion and dissemination of the laxative effect of bran based on scientific reports. It also clarifies that not all fibers have a good laxative effect. Examples are pectin or some synthetic fibers extracted from algae or bacteria. As is known so far, wheat bran is the most concentrated source of fiber and greater laxative effect.

What is the recommended daily fiber intake?
Worldwide recommends Twenty-five grams of fiber per day for individuals whose diets Prev 2000 calories. In men with greater caloric intake (3000 calories) intake of fiber should be thirty-five grams. Unfortunately in many countries, including Argentina, the daily fiber intake does not meet the fifteen grams. We are well below the recommended values. From three to eighteen recommended intake of fiber is calculated by adding five to the age, for example, a six-year-old needs only eleven grams of fiber.

The proportion of fiber foods require more chewing time. Does it contribute to profitability this?
Having to chew longer and because of the ability to absorb much more water and increase its volume, fiber contributes to feelings of satiety. In addition, the Chewing stimulates saliva production which helps in the digestive process. This is a good example of that increasing dietary fiber can achieve weight control. Fiber also may help lower blood cholesterol levels and control blood sugar.

What is the mechanism by which some fiber help prevent cardiovascular disease?
In the gastrointestinal tract fibers bind to bile acids and cholesterol by preventing its reabsorption and thus increasing its excretion. In this way diminishes the pool of endogenous cholesterol and blood levels fall. The fibers cleanse the body helping to eliminate bacteria, toxins and saturated fats.

How does a diet high in fiber changes the bacterial flora in the gut?
Epidemiologic observations show that when consumption prevails a mixed diet in which foods of animal origin constitute a major proportion, develops a variety of species of Bacteroides and Gram-negative bacteria, unlike what happens in diets high fiber. Anaerobic bacteria act on bile acids and cholesterol generating products that can take action to degrade carcinogenic or co-carcinogenic. The flora is varied fiber decreases the amount of potential cancer-causing substances in the colon.

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