The six essential nutrients are carbohydrates, fats, proteins, vitamins, minerals and water. These nutrients are necessary for the normal growth and development of a healthy body. The body cannot synthesize these nutrients on its own, so they need to be included as part of a diet.
Carbohydrates are the major source of energy in the body. They form the major part of food stored in the body to produce energy. They are also important in fat oxidation and can be converted into proteins. Sources of carbohydrates include starchy vegetables, sugars, grains and fruits.
Proteins are the primary structural components of cells. They are responsible for repairing and building body cells. Sources of proteins include beans, eggs, meat and dairy. All the enzymes involved catalyzing metabolic reactions in the body are protein in nature.
Fats are essential in making hormones and steroids. They also serve as solvents for fat-soluble vitamins and hormones. Foods that contain omega-3 fatty acids, such as fish and walnuts, are healthy for the body because they promote growth and development. A person should limit the intake of saturated fats, because they can lead to health problems.
Vitamins are mostly co-enzymes that enhance the normal functioning of enzymes. Vitamin K enhances blood clotting, Vitamin C and E act as antioxidants, and vitamin D maintains calcium homeostasis.
Minerals are inorganic ions needed for enzyme activation. Sodium plays a crucial role in maintaining fluid volume inside and outside the cells and helps the cells to function normally. Potassium prevents excess rise of blood pressure, which may result from excess sodium intake. Calcium helps to maintain and build strong bones and teeth.
Water transports nutrients to cells and maintains homeostasis in the human body. It also plays an important role in removing wastes from the body through urine. Adults should drink six to eight glasses of water a day to stay healthy. Those who wish to lose weight can drink a glass of water before meals to feel fuller.