If you can get all the nutrition you need from whole foods, that is the way to go. For many, however, this is not a realistic possibility. This is where weight gainers and meal replacements can really help - they can provide quick and nutritious meals. Another way to effectively use weight gainers is in your post-workout meal. A quality weight gainer can provide very desirable post workout nutrition by quickly providing the body with a good carb and protein mixture. The best weight gainer for you is the one that best helps you meet your daily caloric goals. If you need more protein, seek a weight gainer heavy on protein. If you are meeting your protein intake goals but having trouble getting to your total daily calorie goal, a product with lower protein content and higher complex carb content may work better for you.