Weight gain supplements have come a long way from the original sugary, bloating supplements of the old days. Most Modern mass gainers like Maximuscle Progain, PHD Pharma Gain, Optimum Nutrition Serious Mass, AST Sports Science Muscle XGF and BSN True Mass offer the highest quality proteins, the right amount of slow digesting carbohydrates and the right amount of calories and nutrients to help you gain lean muscle whilst minimising the chances of adding bodyfat. Weight gain supplements are what are known as ‘nutrient dense’, meaning that every calorie you are ingesting is worthwhile and not ‘empty calories’