What's the best supplement to add protein in my diet for body building?i don't want steroids or any product that has side effects associated.iam a veg

Soy protein: A vegetarian lifestyle can be a healthy one if you know exactly what you are doing and supplement as you must. It makes folks feel good morally, whether or not it really benefits health. I'm very glad you are shunning steroids. Most bodybuilders for some reason strongly prefer whey to soy, if this could be acceptable to you, this might be helpful. Creatine's also worth considering.

Depends: If you eat dairy products you can try greek yogurt or cottage cheese (otherwise soy/almond/coconut yogurt). Non dairy sources include chia seeds, beans, lentils, quinoa, eggs, artichokes, broccoli, avocado, asparagus, tofu, peas, spinach, beet greens, peanuts, pistachios, sesame seeds, garbanzo beans.