Weight gainers are high-calorie products that contain large amounts of carbohydrates and protein. These products can help you gain weight if added to your normal diet. Rich In Fiber.  Weight-gain powders are helpful for increasing calories when you can't increase your calories from food alone. But keep in mind that these products are often quite high in calories (500 to 1,000 calories). Sure, those calories can help you gain weight, but that weight might wind up as fat. It is far easier to control your body composition by controlling your protein, carbohydrate, and fat ratios yourself.Mass Gainers contain a rich amount of carbohydrates. ...Contains High-Quality Whey Protein. Mass Gainers contain high quality of Protein, which is an amazing supplement for bodybuilding. ...Aids In Muscle Recovery & Growth. ...Blend Of Minerals & Vitamins. ...Rich In Fiber. Weight-gain powders are helpful for increasing calories when you can't increase your calories from food alone. But keep in mind that these products are often quite high in calories (500 to 1,000 calories). Sure, those calories can help you gain weight, but that weight might wind up as fat. It is far easier to control your body composition by controlling your protein, carbohydrate, and fat ratios yourself.