Could be he's depressed. People make very poor choices when they're depressed. If it's that or a food addiction the root of the problem needs to be discovered before headway can begin. Talk to other family and friends and see what you can learn from them.

 

A conversation starter like- "hey I'm concerned about John and his weight issue/eating habit/lifestyle choice (however you want to word it). Do you know of anything going on that may be causing this?" Sometimes people tell some friends/family things they won't tell other friends/family due to shame, fear of judgement, etc. Definitely try to connect and make a plan of action of some sort to approach him and get help.

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