Experts warn of weight gain and hormone disruption
There is mounting evidence that despite being hailed as a superfood, soya could in fact pose a serious health risk.
Experts claim soya foods might lower testosterone levels in men, hamper thyroid function, cause weight gain and disrupt hormones.
Soya was first cultivated in China, where it was used as medicine and in cooking. Last year, more than one million tons of it were imported to the UK. It was hailed as a superfood that could fight breast cancer, strengthen bones and ease the menopause.
Once thought of as exotic, today soya can be found in a variety of guises on supermarket shelves, from dairy-free milk and yogurt to vegan cheese and tofu. Surprisingly, according to food-industry estimates, it is also found in 60% of processed foods, adding bulk, flavour and texture. Breakfast cereals, cereal bars and biscuits, cheese, cakes, dairy desserts, gravies, noodles, pastries, soups, sausage casings, sauces and sandwich spreads, to name just a few, often contain soya.
According to recent studies published in the Journal Of Nutrition, soya baby formula could cause problems in male infants. Research at Edinburgh University into the effects of soya milk on young male monkeys found it interfered with testosterone levels, prompting concerns over fertility and disease in grown men.
Furthermore, studies in Japan suggest a high intake of soy-based products can disrupt the thyroid gland, leading to weight gain, fatigue and mood problems.
Marilyn Glenville, nutritionist and author of the Nutritional Health Handbook For Women, says: ‘Soya can block the uptake of the chemical iodine which is needed for a healthy thyroid. Turnips, cabbage, peanuts and pine nuts have similar effects. If you are diagnosed with a thyroid problem, you’ll be told to restrict your intake of all these foods.
‘Don’t overdo it,’ warns Glenville. ‘It is healthy in small quantities, but could be unhealthy if eaten in excess.’ One small portion, about 30g a day is ideal.