Lean mass gainer is a supplement that includes a lot of protein but very little carbohydrates when compared to other mass gainers. Lean mass gainer is advantageous because it increases muscle mass without adding excess or unnecessary fat. Compared to mass gainers, it supports body fat loss at a higher pace. In other words, lean gainers enable you to increase your body mass without consuming extra fat. High-quality proteins from a range of sources make up the majority of lean gainers. There are about 30–35% proteins, 60–65% carbs, and just 4% fat in it.