Why do men develop man boobs?

Breast tissue is different from the tissue in other parts of the body. It contains a lot of fat and very little muscle, and is hormonally driven. Women who lose weight for example will lose fat on the stomach and bottom before they lose fat in the breasts, because their ovaries are producing oestrogen, telling the body to keep the breast tissue at all costs. It is only when they become anorexic that the body at last gives up breast tissue.

Men however have a very low level of oestrogen and a normal healthy male should have a flat chest. So why do some men develop man boobs?

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It is down to oestrogen - but where is the oestrogen coming from?

You would think that with no ovaries, men cannot produce oestrogen, but there is one part of the body that does produce some of it. Your fat cells.

There are three types of oestrogen, and body fat, (also known as adipose tissue), produces oestrone (E1). You need some of this because it regulates the retention of salt and water in your body, hence the reason men have a tiny amount of oestrogen in their system. But as you put on weight, your fat cells have multiplied so much that the oestrogen is starting to stimulate breast tissue.

The reason you hardly ever see a slim male with man boobs is, you guessed it, because they have very little fat. But guzzle those beers and burgers and along with your love handles will come some not so lovely man boobs.

The good news is that they are simple to deal with - just lose weight and as the fat cells shrink, so too will the amount of oestrogen circulating in your body. Less oestrogen = fewer signals to your brain to grow breast tissue.