Protein often gets all the credit when it comes to making gains, but fat is an important part of muscle growth, too. While dietary fat (i.e. the fat found in foods such as nuts, avocado and oily fish) can’t directly build muscle, it does play a significant role: Eating healthy fats is important for absorbing essential vitamins and producing energy and hormones necessary for muscle growth. Dietary fat protects cell membranes, the vital exterior of every cell, and sheaths surrounding nerves. It’s also essential for muscle movement, blood clotting and inflammatory response, which helps the body repair from injury after training. If gaining muscle is your goal, getting around 15 to 20 percent of your calories from fat is ideal,