Protein Your body uses proteins--the muscle maker--to also build and repair bone, tissue and skin. Fiber Roughage keeps you running smoothly and has other health benefits. Minerals Minerals play a unique role in our bodies. Phytochemicals Plants have special chemicals that may fight disease. Carbohydrates Carbohydrates provide high-octane fuel for energy. Vitamins These 13 nutrients are vital for vim and vigor. High Cholesterol The buildup of plaque that can bring you down. Caffeine Learn about the world's most popular stimulant. Food Additives What's in that stuff? Water Make a splash with this silent nutrient.