No great chef is obese, but many are or have been a bit puffy. Den Blijker, Jonnie Boer, Escoffier, Robuchon, Hermé, Savoy, Schuhbeck. But I can name about twice as many that are not. None that are obese. Not while they were cooking and I looked them/their books/recipes up. If you can cook you know good food, and though you may overeat, I know I have, if you know your way around a kitchen, you will sort it out before you get too fat.