Let's get serious about soya - what are the health benefits?
It seems like soya products are everywhere you look these days, with many vegetarians and vegans turning to soya as an alternative to meat. Soya can be added to your diet as a great protein source, or you can ditch dairy with alternatives such as soya milk, cheese and yoghurt. We wanted to understand a bit more about soya – and let our readers know the pros and cons – what is it, how healthy is it and what are the benefits (and downsides) of adding it your diet?
A gentle introduction
Let's start with some background about the humble soya bean. It grows in a pod, not dissimilar to peas and other beans, and whilst usually green in colour, It can also be black, brown or yellow. Fresh soya beans (known as edamame) are popular in Japanese and Asian cuisine and you'll often find them served steamed in their pods at restaurants (don't eat the pods!)
Soya bean plants originally came from China, where they have been cultivating them for more than 13,000 years; the ancient Chinese viewed the crop as a necessity. Centuries later, soya beans began to reach other parts of Asia, but it wasn't until the early 1900's that they began to be used in the west for food. Nowadays, soya beans the most widely grown legume on the planet and we are consuming more soya foods than ever before, such as soya cheese and soya milk.
What are the nutritional benefits?
Soya is a great alternative to meat and it's packed with protein, essential for repairing muscle and tissue and giving you energy, plus helping you to feel full (and less likely to reach for unhealthy snacks). 100 grams of soya beans contains 17g of protein, but the beans are also known for their high fibre content. This means soya products are a great way to tackle constipation, aid digestion and reduce your risk of type-2 diabetes and high cholesterol. They're low in saturated fat too with just 1g per 100g serving.
What can soya do for your health?
Soya products, when consumed as part of a healthy diet, can benefit your health and well-being in a number of ways. Soya naturally contains phytoestrogens called isoflavones. The two soya isoflavones are known as genistein and daidzein, and they've been the subject of much research (and much controversy). It's thought that they could reduce the risk of breast cancer, but the jury is still out on this claim!
At any rate, the phytoestrogens in soya can help to even out your hormonal balance – if the ratio of progesterone and oestrogen in your body is out of sync, they can help to rebalance it. This means that many women turn to soya to improve symptoms of conditions such as endometriosis and PMS – soya could even boost your mood! As women enter the menopause and their bodies naturally stop producing oestrogen, many menopausal women include soya products in their diet to boost their oestrogen levels and relieve symptoms (1).
Phytosterols – what's all the fuss about?
Soya beans contain compounds known as phytosterols, which have a similar structure to cholesterol. One of the main health benefits of soya is that these compounds can inhibit the absorption of cholesterol, making them ideal for anyone trying to actively reduce their cholesterol.
The controversy surrounding soya
Despite these numerous health benefits, there has always been controversy surrounding soya, and since the 70s, when consumption of soya products across the globe saw a marked increase, this controversy has only increased. Many people claim soya disrupts hormone levels and the isoflavones in soya can affect normal body function. Studies in animals show that soya isoflavones could cause breast cancer.
A study into the effects of soya on breast tissue was carried out with a group of 48 women. The women were split into two groups – one group ate their normal diet, whilst the other group supplemented their diet with 60g of soy protein a day. After two weeks, the women in the soy protein group showed a significant increase in the number of epithelial cells in breast tissue – these are the cells most likely to turn cancerous (2).
These changes could indicate an increased risk of breast cancer linked to consumption of soya products, but other studies have shown women who add soya products to their diet may have a reduce risk of breast cancer, so it's best to not get too hung up over statistics.There are also claims that oestrogen in soya could affect male reproductive health, after studies were carried out which showed men eating higher levels of soya have lower sperm counts (3). There's no proven link as yet though.
Should you consume soya as part of a healthy diet?
We believe that no food is bad for you, in moderation (ok, maybe with the exception of Krispy Kremes). On a serious note, though, the controversy surrounding soya hasn't yet drawn any conclusions as to whether it is a healthy addition to your diet or not, and we say that something so low in fat and high in protein (and natural too) can only be beneficial, in small quantities. Tofu, tempeh, soya milk, cheese and yoghurt are all great additions to your diet, and tempeh can be used in soups, salads and stir fries for a protein boost that's ideal if you don't eat meat. So if you want to add soya products to your diet, then do so, but make sure you look for the simplest, least processed products with no added artificial ingredients – you can add spices and natural flavourings to tempeh, tofu and even soya yoghurt at home!
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