Yam is full of vitamins and minerals, making it highly nutritious. This fruit also contains a compound called diosgenin, which enhances brain function and improves learning ability. Yams are rich in antioxidants, which are known to rebuild skin cells and may reduce oxidative damage caused by free radicals. yam contains vitamin C, which helps promote collagen production in the body. Collagen is a protein that is effective in maintaining the skin's elasticity.