Facts and myths about soy

Soy is a good vegetarian choice

Fact. Soy products such as soy drink, tofu, tempeh and meat substitutes are made from soybeans. The soybean is a nutritious bean: it is rich in vegetable protein and healthy unsaturated fat. It also contains many vitamins and minerals, such as iron and vitamin B1. This makes soy products a good vegetarian choice from a nutritional point of view. Choose variants to which vitamin B12 has been added, because that is only found in animal products and not in soy. If you replace dairy with soy, make sure that not only vitamin B12 has been added, but also calcium.

Soy contains hormone-like substances

Fact. Soy contains so-called isoflavones. These are substances that are very similar to the female hormone estrogen and that is why they are also called phytoestrogens (plant oestrogens). But isoflavones have only a very weak estrogen effect. And so soy is not the hormone bomb as is sometimes claimed. Men can also safely eat soy without fear of breast formation. In Asia, soy products have been eaten for more than 4000 years, also by men and without known side effects.

Soy helps with hot flashes

Fact. It has been known for some time that women in Asia suffer much less from hot flashes during the menopause. This is probably because they eat so many soy products such as tofu (bean curd), tempeh, miso and natto. Soy also helps in Western women, according to research. Women suffer less from hot flashes if they consume the amount of isoflavones from two servings of soy daily. The hot flashes are also less severe.

Soy lowers cholesterol

Fact. According to the Health Council, soy helps to reduce bad LDL cholesterol levels. Soy contains several ingredients that could be responsible for this: soy proteins, fiber and unsaturated fats. It is not yet known which ingredient has the most effect.

Women get breast cancer from soy

fable. In fact, the opposite is rather true. Soy products could reduce the risk of developing breast cancer. Women who have been used to eating soy products from childhood, as is customary in Asia, appear to have a lower risk of breast cancer. However, it is not yet clear whether this beneficial effect also applies to Western women.

Soy is not recommended for breast cancer

Fable/fact. Soy supplements in tablet form are not recommended in hormone-sensitive breast cancer, because they counteract the effect of hormone therapy (tamoxifen). Ordinary soy products such as soy drink and meat substitutes based on soy are safe to use in hormone therapy. In non-hormone-sensitive breast cancer, soy products may even be beneficial. There is research showing that the chance of developing breast cancer again or dying from breast cancer is lower in women who consume two servings of soy per day. However, more research needs to be done before definitive conclusions are reached. In any case, it is clear that soy products are safe for all forms of breast cancer.

Soy increases prostate cancer risk

fable. In fact, it seems that soy products can lower the risk of developing prostate cancer. These indications come from two studies of more than 200 men with an elevated Prostate Specific Antigen (PSA). They are at a higher risk of developing prostate cancer. The men who used soy products developed prostate cancer less often than the men who did not. These are still small studies, so definitive conclusions cannot yet be drawn.

The vegetable proteins from soy are not complete

fable. In general, it is true that animal proteins are more complete than vegetable proteins. But soy is an exception. Proteins contain amino acids, which are building materials for our body. We cannot make some amino acids ourselves, so they must come from our diet, just like vitamins. These essential amino acids are abundant in animal products, but plant products are generally less favored. Except soy: it also contains all the essential amino acids. That is why soy is a good meat substitute.

Soy is part of a healthy diet

Fact. Soybeans are officially counted as legumes, just like chickpeas, lentils and beans. The Health Council recommends adding legumes and/or soy to the menu every week. This recommendation is barely achieved in the Netherlands. On average, we only eat legumes once every three weeks. On average, we only consume two grams of soy per day. So feel free to take soy drink, soy yogurt, soy beans, tofu or tempeh more often.