Why is Akshay Kumar totally against protein shakes and supplements where these are good for health?

He follows the approach of you being a product of your mother(Which is the nutrietns and food that your mother fed you from your childhood to you become an adult, as obvious the food which you are fed into from the childhood mostly describes the kind of body and immune system you will have.

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Thus he is a good believer of the old school theory of Dara Singh time which belief in the old school theory of nutrition and workout, he does not indulge in any weight training but goes for bodyweight exercises like pullups, pushup swimming and many of the core exercises.