Is soya dangerous for men? Can soya turn men into women, or is it all just hyperbole?
A couple of months ago the Daily Mail Online published and article titled, Soya Could Make Men Infertile.
"The increasing amount of soya being eaten in Britain could be putting the fertility of a generation of men at risk, according to an alarming new study."
Daily Mail Online
The study that they used as a source isn't named but, can be found online in the Journal of Urology, is being used to claim that there is fear, amongst experts, that exposure to compounds found in soya, either in the womb or through breast milk, could lead to reproductive abnormalities in boys.
Studies on Fertility
The study that the Daily Mail Online, on which the whole premise was set, was carried out 20 years ago by scientists based at Johns Hopkins University in Baltimore in the USA who were looking at the effects of a chemical found in soya beans, genistein, on pregnant rats. In their article the Daily Mail Online uses the study to argue that soya is the cause for the drop in male fertility in the UK. That there is a connection between the number of couples that seek fertility treatment and the amount of tofu that is eaten in the United Kingdom. The problem is that the study was carried out on rats. The scientists that were involved in the study use a lot of qualifiers such as "may", "could" and "appears". They are also quoted as saying "additional research is needed". So, basically, no conclusion has been drawn and there is no direct link to what they found and how the chemicals in soya beans affect human fertility.
So far, studies that have been carried out on humans have found no evidence that eating soya, including tofu, tempeh or drinking soya milk has any negative affect on human fertility. In fact studies have found that soya helps regulate women's hormones and improves health. Other studies, that are available online, have found no link between the consumption of soya and low fertility in men.
"Overall, there are some indications that phyto-oestrogens, alone or in combination with other endocrine disruptors, may alter reproductive hormones, spermatogenesis, sperm capacitation and fertility. However, these results must be interpreted with care, as a result of the paucity of human studies and as numerous reports did not reveal any adverse effects on male reproductive physiology."
Christopher R Cederroth 1, Jacques Auger, Céline Zimmermann, Florence Eustache, Serge Nef
Increased Soya Consumption
For the last 20 years, there has been a significant increase in the amount of soya that people are consuming. This rise is a result of individuals exploring more diverse meals, trying traditional dishes from other countries, and a growing awareness of the health benefits associated with soya and soya products. Soybeans are a rich source of plant-based protein, providing a complete profile of essential amino acids, along with various micronutrients such as B vitamins, copper, iron, and zinc. Studies and observed effects from consuming soy and drinking soya milk, have indicated a lower cancer risk, reduced cholesterol, reduced menopausal symptoms, and health advantages that are prompting scientists to explore the potential of developing soya supplements.
Like other plants, soybeans contain phytochemicals; in soybeans, these include isoflavones, which are now being isolated and studied for their potential to reduce health risks and improve the well-being of those already affected by diseases, alleviating symptoms. Soya, for those who aren't allergic, is a valuable addition to a balanced diet. As more people recognise the importance of adopting a balanced and sustainable diet, the increase in soya consumption will contribute to a positive shift towards healthier eating habits, with significant implications for both human health and the environment, as animal-based protein is replaced with plant protein.
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