Soy! Does it Really Give Men Boobs?


Regardless of what you wish to call them – ‘man-boobs’, ‘moobs’ or ‘mannaries’ – enlarged male breasts can be a genuine and serious cause for concern amongst some members of the male population, both young and old alike.

One of the main concerns of soy is that it causes this problem. But does soy actually hold the potential to give men larger breasts?  What’s the science behind such a suggestion?

The root of the concern lies within the contents of soy itself, primarily phytoestrogens which act as a mimic of the estrogen found in females, which triggers the development of various sex characteristics, breast growth included.

A famous case in the US in the late 2000’s found former Vietnam vet James Price with unexplained breast growth, hair-loss on his arms and erectile problems. A number of doctors failed to diagnose his case until it was found he had up to 8 times the normal levels of estrogen in his body – higher than that of an average female. It was also discovered he was consuming up to 3 quarts of soy milk a day (3 litres or 6 pints) – excessive to say the least.

So case closed, right? Well, no, not quite.

These phytoestrogens are found in a huge range of products including soy products, lentils, apples, beer, beans, coffee and even carrots. Whilst the removal of soy from Price’s diet returned his enlarged breasts back to normal, he is an extreme case.

Dr. Richard J Santen, medical professor at the University of Virginia, states that in his lifetime of hormone research he has “never found a correlation between soy consumption and feminisation”. What’s more, a 2010 study by Mark Messina, researcher at Loma Linda University School of Public Health concluded that “isoflavones (phytoestrogens) do not exert feminizing effects on men at intake levels equal to and even considerably higher than are typical for Asian males.” 

Messina here is referencing studies that average Asian diets include a higher proportionate consumption of soy than their Western counterparts, yet we are not witnessing a ‘man-boob’ epidemic across Asia just yet.

As with any material consumed by the body, individuals may experience different responses. With regards to soy being heavily linked to increase in male breast size, the comprehensive cold hard evidence just isn’t there to support it.

Image Credit: Mirror