10+ Foods You Can Eat Freely Without Weight Gain Concerns
Protein
Protein is essential for building muscles and should be part of everyone's diet. It helps signal fullness to your brain by increasing levels of peptides and amino acids in the stomach. Aim for protein to make up about 20 to 30 percent of your daily calorie intake.

Our bodies use protein to repair tissues, produce enzymes and hormones, and support growth in bones, skin, and blood. Since protein is a macronutrient, we need a significant amount of it daily because our bodies don't store excess protein.