Recently, in different sources you can hear the expression: "A knife in the back of vegans." What does this mean and how is it associated with phytic acid? First of all, we note that this applies exclusively to food. No worldview or other views are taken into account.
People who follow a certain diet, who call themselves vegans, have foods containing a substance called phytic acid as their main source of nutrition. The attitude of specialists towards it is becoming more and more negative. We learn more from the article why.
How phytic acid works
Many have long heard that whole grains, raw nuts and seeds, bran and legumes are the key to a healthy diet. But recently, a completely different opinion has begun to be met.
The fact is that these and some other products contain phytic acid. This substance blocks phosphorus, calcium, iron, zinc and magnesium. Phosphorus is known to be necessary for bones and teeth. Contained in plant products, it is stored inside phytic acid, which makes it inaccessible to humans. In addition, phytic acid disrupts the functioning of enzymes such as trypsin and pepsin, which are used to digest food.
Naturally, what has been said does not mean at all that one must abandon the named products forever. Moreover, these provisions are not fully proven, and scientists are still arguing about the effect of phytic acid. The benefits and harms are interpreted in two ways. But we will consider for now the point of view whose adherents oppose the substance.
Food content
The huge amount of phosphorus contained in the above foods is mainly phytin, that is, one that cannot be absorbed. If the diet contains phytic acid in large quantities, it reacts with calcium, resulting in the formation of insoluble chelates. Thus, such important trace elements as fluorine and calcium are lost by the body. In addition, it is known that a large percentage of other important substances - magnesium and zinc without this acid is absorbed much better.
In addition to the type of plant, the content of phytic acid depends on the location and method of cultivation. For example, it is much larger in cases where it is grown using a high percentage of phosphate fertilizers.
Most of it is in bran and seeds. Therefore, the benefits of oat bran are put under a big question mark. If cocoa beans are not fermented, then they also contain a large amount of phytic acid. In food, the table below gives exact numbers.
Harm
Unfortunately, more and more evidence confirms that a diet high in phytic acid causes mineral deficiency in the body. So, those who consume a lot of cereals, common diseases such as osteoporosis and rickets.
If such a diet lasts a long time, then the metabolism slows down. A mineral hunger strike begins. For an adult, the process is not as critical as for a child. In a growing body, such nutrition is fraught with poor development of the skeletal system, stunting, unhealthy teeth, narrow jaws, and also leads to anemia and even mental retardation.
Research and experimentation
The fact that phytic acid has such an effect was demonstrated back in the middle of the last century by Edward Wellanby. He managed to prove that high-fitin cereals disrupt the development of the skeletal system and the metabolism of vitamin D, as a result of which rickets begins. But vitamin D can neutralize acid to some extent.
Experiments have shown that whole grains, in comparison with white rice and unbleached flour, have more minerals. But at the same time, they contain more phytic acid.
On the other hand, it was proved that if ascorbic acid was added at the same time, it would significantly reduce the harmful effects of phytic acid.
Later, already in 2000, a number of studies were also conducted, during which other factors that neutralize the harm of acid were found. Iron, together with keratin and vitamin A, creates a complex that does not allow itself to absorb phytic acid.
Phytase to help health
In plant products, which contain the substance under consideration, also contains one that neutralizes the action, freeing phosphorus. It is called phytase.
Thanks to phytase, ruminants do not have problems with phytic acid. This substance is found in their body, in one of the departments of the stomach. Those animals that have one stomach also produce phytase. But its number is many times less than the first. But in this sense, the mice were very lucky: they have more than thirty times more phytases compared to humans. That is why mice can eat cereals in large quantities with virtually no harm to themselves.
But the human body in a healthy state has the lactobacillus lactobacili and other microorganisms that are capable of producing phytase. Therefore, even if many products are used that contain phytic acid, neutralization occurs due to these microorganisms, making food safe.
Germination
It has been proven that phytase appears due to germination, reducing phytic acid. Soaking in acidic and warm liquids is also very useful, as, for example, when preparing sourdough bread.
Previously, until agriculture was developed on an industrial scale, farmers soaked the grain in hot water, and then fed them animals.
But not all cereals contain the required amount of phytase. For example, its quantity is not enough in oats, millet and brown rice. Therefore, phytic acid in oatmeal, millet and rice porridge with regular consumption in large quantities, according to some scientists, can negatively affect health. But in wheat and rye phytase is much more. And if you still soak and ferment these two grains, then phytic acid will not be able to cause harm, as it simply disappears completely.
It is noteworthy that at a temperature of 80 degrees under normal conditions and at 55-65 degrees in a humid environment, phytase will very quickly collapse. Therefore, it is better to abandon extrusion whole grain bread if you do not want to get digestive problems.
It contains a little in oats, and when heated, it completely loses activity. However, for its destruction, even grinding at high speed is enough. There is more phytase in fresh flour than in one that has stood for several months.
How to neutralize phytic acid
To activate phytase, and the presence of phytonic acid is reduced, one heat treatment is not enough. It is imperative to soak the cereals or legumes in an acidic environment. Then this combination can eliminate most phytates.
Consider how this is done with a specific example of quinoa or quinoa.
If the product is boiled for 25 minutes, then 15-20% of the acid will decrease.
Soaking from 12 to 24 hours at a maintained temperature of 20 degrees and subsequent boiling will leave 60-77%.
If fermentation is carried out with serum from 16 to 18 hours, maintaining a temperature of 30 degrees, and then boil the product, the percentage of purification will increase to 82-88.
When soaking for half a day, germinating for 30 hours, lacto-fermentation from 16 to 18 hours and after this boiling for 25 minutes, phytic acid will be eliminated by 97-98%.
Both soaking and germination perfectly help in eliminating the substance, but are not able to completely get rid of it. For example, if it contains 57% in barley, wheat and green beans, germination will be more effective than frying.
This is the best way to reduce phytic acid in legumes, but not completely. For example, after 5 days of germination, almost 50% of it will remain in lentils, 60% in chickpeas, and 25% in black-eyed beans.
The process will be more effective if germination is carried out at high temperature. So, in millet 92% will be destroyed. Well, at normal temperature, this procedure is a good preparatory step for the maximum disposal of harmful substances.
Roasting
Phytic acid is already found in much smaller amounts after treatment. But it would be better if you first soak the product with the one where there is additional phytase, even before the start of the heat treatment.
Soaking
In corn, soy, millet and sorghum, when soaked for 24 hours, the acid content will decrease by 40-50%. In cereals and legumes - by 16-20%.
For cereals, which contain a large amount of phytase (this is a rye and wheat product), it is best to make starter culture. In just four hours, about 60% of the acid will be removed from wheat flour at 33 degrees. Fermenting bran within 8 hours will reduce its content by 45%. And if fermentation is carried out with sourdough for 8 hours, then phytic acid will not remain at all in whole-grain bread.
Experiments have shown that if industrial yeast is used in home baking, the effect will be much less successful. For example, in whole grain bread, only 22 to 58% of phytin will be eliminated by yeast.
Norm of phytic acid content in products
Of course, it is not necessary to completely abandon products with phytic acid. The main thing is to understand how to reduce its content, and to do it. Then phytic acid in food will remain at an acceptable level.
Interestingly, in the diets of different countries, the content of this substance is different:
- in America, it is 631 mg;
- in Britain - 764 mg;
- in Finland - 370 mg;
- in Sweden - 180 mg.
If in the diet there is food with a high content of vitamins A, C, D, as well as calcium, high-quality fats and lacto-fermented vegetables, then health is usually normal. For a person with good health, the content of the substance is acceptable in the range of 400-800 mg. For those whose teeth are destroyed and their bones deteriorate, its consumption should be brought to 150-400 mg.
A healthy diet should contain no more than 2-3 servings of dishes prepared correctly from foods that contain phytic acid. If they are consumed daily, they will benefit the body. But if such products become the main food, then this can cause health problems.
The benefits of phytic acid
In fairness, you need to consider the other side of the issue. We can not say that phytic acid alone carries problems. The benefits and harms in it for a person accompany each other.
In industry, phytic acid is used as a dietary supplement of plant origin, called E391. In the field of medicine, it is added to medicine for the treatment of the nervous system and liver.
Even in cosmetology, the substance found its application as a cleansing procedure - peeling. The raw material is obtained in this case from a cake of wheat grains. Peeling not only effectively exfoliates the skin, but also fights pigmentation and inflammation. In this case, the skin does not even remain irritation inherent in this procedure, carried out with other drugs.
More recently, acid was actively added in the manufacture of alcohol to cleanse foods from iron. But when work appeared on the dangers of the substance, they decided to abandon it.
Conclusion
Today, very mixed opinions are caused by phytic acid in products. The table in the article will help you to find out how to reduce its content in food before eating.
It is worth noting that at present, only ourselves can provide ourselves with a healthy diet. Therefore, decide how important this is for you and whether it is worth doing slow but proper cooking.