It might sound surprising, but some foods, estrogenics, change hormone balances in men and can cause men to gain weight in surprising places (like their boobs).
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Weight loss: I was taunted by my close friend for having man boobs - Times of India
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How to Lose Man Boobs Fast and Naturally: Get Rid of Man Boobs Once and for All: L.David, Kenneth: 9781304279811: : Books
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