For throughout a day for example if I overeat by 50 calories or whatever ?

I wouldn't say formula as much as simple math. If you consume more calories than you burn off, you gain weight. If you consume less calories than you burn off, you lose weight. It's as simple as that...really. Now what you do with the extra calories is up to you. If you weight train, the extra calories will not make you fat as much as help your muscles to grow. No activity....means it turns to fat. Overeating by 50 calories probably wouldn't have that much of an effect on your weight. There are websites that can give you the right amount of calories you need depending on your age, sex, wieght, etc. Whatever it is, consume less to lose weight.

CALORIES CONSUMED <<<<< CALORIES BURNED

e - f = s

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