Protein is vital for numerous body functions, including the development of cells, and the health of muscles, skin, hair, and nails. Lack of protein can lead to symptoms like fatigue, weak hair, skin, and nails, slow wound healing, mood swings, cravings, and reduced muscle mass. Protein is vital for numerous body functions, including the development of cells, and the health of muscles, skin, hair, and nails. Lack of protein can lead to symptoms like fatigue, weak hair, skin, and nails, slow wound healing, mood swings, cravings, and reduced muscle mass. Health and Fitness, Health Tips, Exercises & Workout Tips, Diet & Wellness | Times of India Lifestyle