Is Soy Safe To Eat? From a Plant Based Dietitian

August 11, 2017

Over the last couple of years, there has been a substantial rise in concerns around whether soy is safe to eat. This is often the result of sensationalised media stories on the topic of soy. Unfortunately, this has led many people to believed that soy is bad for health and may choose to limit or avoid soy altogether.

One of the most common questions asked about soy is whether firstly, do men who consume soy have more fertility issues and secondly, does soy cause breast cancer. In this article, we’ll take a deep dive into these topics.

Health Benefits of Soy

Soy beans are beneficial due to being a source of highly digestible, quality protein, are high in iron and omega 6 fatty acids. It has previously been thought that the absorption of iron from plant-based sources is relatively low, however recent research has indicated that iron absorption from soy milk may be quite high. When soy milk has been fortified with calcium, the absorption of calcium by the body is similar to that of cow’s milk and therefore is also an essential source of calcium for those following a dairy-free diet

What foods contain soy?

The consumption of soy differs between Asian and western populations. Soy products in Asia are often minimally processed and can be found in the form of boiled soybeans, tofu, miso soup, natto and soy milk. However, in western society, there is a higher proportion of processed soy products consumed. This is primarily found as soy flour, textured vegetable protein, isolated soy protein and soy milk.

Is soy safe to eat?

Each gram of soy protein in traditional products contain approximately 3-4mg isoflavone, however, during processing this often results in products with a reduced isoflavone: protein ratio. The estrogen-like effect of isoflavones are responsible for the increased concerns about the impact of soy consumption. However, current research has found no significant effects of soy consumption on the body, when looking at indicators of male infertility, testosterone levels , oestrogen levels and prostate cancer risk. When investigating the concern regarding breast cancer and soy consumption, studies have found that soy either has a protective or no significant association.


It is important to highlight that the research in this area still developing and there is still an incomplete understanding of the health effects of soy in humans. As a result, research is still being undertaken to fully understand this issue.


Loving our article Is Soy Safe To Eat? Read our article on how Vegan Diets Can Reduce Cholesterol


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