3 myths you’ve always heard about soy, but that don’t make sense –

1. Favors the appearance of breast cancer

You may have heard that soy increases estrogen levels in the body – a hormone that, in excess, is linked to the onset and worsening of breast cancer.

But most research shows that eating the food actually prevents the recurrence of this type of cancer for those who have already suffered from the problem. Another advantage: “its consumption also reduces the mortality rate among people with the disease”, says Renato Zilli, an endocrinologist at Hospital Sírio Libanês, in São Paulo.

These benefits are due to the fact that soy is rich in isoflavones, substances that protect DNA. In addition, the vegetable blocks so-called nitrosamines, carcinogens. “Soy also contains essential amino acids, phosphorus and zinc, which have antioxidant properties”, explains Maria Flávia Sgavioli, nutritionist at Estima Nutrição, in São Paulo.

2. It causes infertility

Between 2008 and 2009 some studies popped up saying that the high intake of soy would be related to the decrease of fertility hormones. But most of the scientific evidence shows the opposite: the seed, in fact, is capable of increasing the chances of conception.

This is because soy isoflavones have a structure similar to that of estrogen, an essential hormone for pregnancy to occur. “In cases of deficiency, food works as a kind of supplement, favoring fertility”, explains Maria Flávia.

But calm down: before going out eating a lot of soy, talk to your doctor to find out the ideal amount of the vegetable you should consume. It’s also important to check if, in your case, this is really a good option to increase the likelihood of a baby coming.

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3. Not recommended for physical activity practitioners

Nothing to see! In 100 grams of soy there is almost twice as much protein as the same amount of red meat. And the protein content of the seed is of high biological value – that is, it provides all the amino acids our body needs.

“The food still has a low fat content and is rich in fiber”, points out Renato. So, if gaining lean mass (and health) is your goal, you can bet on soy without any problems.