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1st, understand that if being slim runs in the family, there's not much to be done since you're already predisposed to have a high metabolism to burn calories quick.

2nd, increase carbohydrate diet and a sedentary lifestyle. You accumulate more fats this way. It's unhealthy because you're just setting yourself up to be sick and fat.

The healthy route is eating more protein to bulk up while exercising.

Alright, sedentary lifestyle is not for me no matter how hard I try. So I will stick with the protein and exercise. Thank you