Whole grain products are not harmful PART 2
Animal administration of extremely high concentrations of lectin wheat germ, ie 500 mg / kg body weight, affects irreversible the intestinal wall. In humans, however, the administration of a single 200 mg dose did not produce any harmful effect. This is because perhaps is absorbed just a little amount of lectins, because the intestinal epithelium has a protective layer containing glycoconjugates, and the intestinal surface is particularly large, which makes the lectin to not have any toxic effect.
Today they know that lectin may even have positive effects on intestinal digestion, the intestinal immune and hormonal system and microbial flora. Furthermore, the histological studies have shown that lectin has an inhibitory action on the occurrence of intestinal cancer.
Inhibitors in relation to some enzymes, alpha amylase inhibitors and proteases inhibitors have have to be said that they are not specific components of whole grains. They are also found in white flour, as in many other vegetable foods. In fact, not all inhibitors contained by the whole grains are active against the human digestive enzymes, and much of the enzymes inhibitors are destroyed at temperatures of food preparation.
Moreover, in people with normal eating habits, enzymes inhibitors even have a health-promoting action, influencing the blood glucose concentration and preventing the emergence of cancer.
Finally, a word about PHYTIC ACID, which is found in the seeds of all plants, especially whole grains, vegetables and nuts. In adults, the average intake of phytic acid differ depending on the eating habits, being between 0.3 and 3 g / day.
In the digestive tract, in certain circumstances, phytic acid may fix some essential and mineral substances, preventing their absorption, for eg iron and zinc absorption. But practicaly, the phytic acid doesn’t influence and doesn’t prevents the absorption of zinc and iron. In the recent years, the clues that phytic acid has beneficial actions on the glycemic control and cancer prevention are multiplying.
A study conducted at the Giesen University, Germany, showed that pregnant women who are fed with whole grain cereal products had higher blood vitamins concentrations, zinc and other minerals than the ones with a mixed alimentation.
The zinc absorption of vegetables was 30% higher than those who also consumed animal products.
Sustaining that total vegetarians should present a zinc deficiency, beacause the whole grain products would make the minerals absorption harder has been shown to be unfounded.
Rich minerals and vitamins are found in layers enclosing the beans, the bran and in germ. It is true that there is also found the phytic acid, which forms complexes called phytates with mineral substances like iron, calcium and magnesium, as well as with microelements – copper, zinc, manganese – and proteins. However, the food preparation processes – soaking in water, cereals germinate, boiling and baking – can reduce the phytate content. For example, in the rye bread can be demonstrated the total disappearance of phytate, irrespective of the manner of preparation. Even in the whole wheat flour bread, half of the phytate is destroyed. Keeping the grits in water about 10 hours during the night achieves a 20% reduction of phytate. And even if fitini fix a part of mineral substances, it presents advantages influencing better the glycemia and fats. Furthermore, the phytate decreases the risk of developing colon cancer and slows its evolution.
Enzyme inhibitors from whole grains prevents the full digestion of starch. This starch, non-absorbed, arrived in the colon, is attacked by bacteria there and thus take birth short chained fatty acids, which have protective action on the intestinal epithelium. Research shows that people who ingest larger quantities of enzyme inhibitors presents a smaller risk of breast cancer, prostate and colon.
The pigments that colors the fruits and vegetables are powerful antioxidants, known as flavonoids. In the bean shells, which makes up about 10% of the grains, are found, in addition to fiber, large amounts of flavonoids. But not only the colored beans, but also the white and black contain these flavonoids, an additional reason for the rehabilitation of vegetables.
It is true that, in people with a certain genetic predisposition, grains can produce celiakia or gluten intolerance and allergies. But these are due to the proteins from cereal products without having nothing to do with lectins, enzymes inhibitors or phytic acid.