<       A friend asked: "I am a vegetarian, only through the beans and soy products to supplement the protein, but some people told me that eating beans affect the absorption of iron, will cause anemia, is that right?
      Phytic acid polyphenols affect iron absorption
      There are two very different views on beans and iron. Some experts believe that eating beans is beneficial to iron supplementation, because the iron content of legumes is significantly higher than cereals, even higher than some meat. Another part of the experts said that beans, iron, zinc and other trace elements content is high, but the absorption rate is very low. If you do not pay attention to diet with beans as the main source of protein vegetarian anemia risk is relatively large.
      From the food ingredients table, the iron content of beans is indeed relatively high, even higher than some meat products. For example, the iron content of kidney beans can be as high as 7 mg per 100 grams, while 3.9 mg of lamb. However, research has long proved that beans also contain a considerable number of factors that impede the absorption of iron, the most important of which is phytic acid and polyphenols. These two substances are important in the beans "anti-nutritional" ingredients, can delay the digestion and absorption of protein and starch, but also reduce the absorption rate of minerals. In 1984, a study found that black beans, lentils, green beans and other legumes in the iron absorption rate of only 0.8% to 1.9%.
      The study found that the higher the phytic acid content in food, the lower the absorption rate of iron, zinc and calcium. While polyphenols, despite having very good antioxidant properties, hinder the mineral absorption is its drawback. The study found that almost all kinds of polyphenols have a role in hindering the absorption of non-heme iron. In addition, there are a small amount of oxalic acid oxalic acid, it is also a common obstruction of mineral absorption of plant components.
      Vegetarians should eat fermented legumes
      Although the phytate and polyphenols in the beans will greatly reduce the absorption of iron in the beans, but does not necessarily cause anemia. This is due to the following three reasons:
1. Phytic acid and polyphenols in legumes These ingredients only act on iron in plant foods and have no effect on heme iron in meat. Meat iron in the form of heme, there is chelating state, can be successfully absorbed by the body. So, as long as the amount of red meat in the diet, you do not have to worry about iron deficiency problems. At present, the amount of meat consumed by our residents is large, because the risk of anemia is not large. On the contrary, male hi meat residents with some beans to replace meat, reduce iron intake, but favorable to prevent disease.
2. Vitamin C in food can greatly improve the absorption rate of iron, so as long as the dietary intake of vitamin C-rich foods, and beans with food, you can very effectively offset phytic acid and polyphenols The adverse effects of iron absorption. Other organic acids such as citric acid, malic acid, lactic acid, acetic acid, etc. will also promote iron absorption, so with fruit, vegetables and beans with iron can solve the problem.
3. Beans after some processing, you can significantly reduce the phytic acid composition, effectively improve the iron, zinc and other elements of bioavailability. The study found that soaking, germination, fermentation are effective methods. In particular, the fermentation effect of mold and yeast is particularly good. One study found that the first soaking and re-fermentation, you can remove beans in 88% of phytic acid. So, for vegetarians, sauce tofu, tempeh, soy sauce and so are a very good source of minerals.
      In general, in the case of non-vegetarian food, both meat and fruits and vegetables, because the consumption of beans is unlikely to occur iron deficiency. Many studies have proved this point. For the intake of animal food is more adequate people, especially obese, high blood lipids, the intake of beans can get a lot of dietary fiber, polyphenols antioxidant substances, but also get a wealth of B vitamins, slow digestion Starch and vegetable protein, the prevention of chronic diseases is very helpful for the nutritional balance is also beneficial and harmless.

      For vegetarians, consider eating more fruits and vegetables while eating beans and giving priority to fermented legumes in order to increase plant iron and other mineral utilization and avoid anemia and other nutrient deficiencies The In addition to beans, there are many foods that can provide iron, such as hazelnuts, almonds, black sesame seeds and other nuts and oilseeds. Hawthorn, jujube, longan and other foods in the iron is easier to absorb.