The nutrients known to be essential for human beings are proteins, carbohydrates, fats and oils, minerals, vitamins, and water. To function, the human body must have nutrients. The nutrients known to be essential for human beings are proteins, carbohydrates, fats and oils, minerals, vitamins, and water. Proteins Proteins are made of amino acids, small units necessary for growth and tissue repair.
Protein is the body's most plentiful substance except for water and, possibly, fat.
Animal foods such as meat, fish, poultry, milk, and eggs are rich in protein. Good plant sources of protein are beans, peas, nuts, bread, and cereals. Combining plant sources, such as peanut butter with whole-grain bread or rice with beans, provides excellent protein. So does combining plant and animal sources such as cereal and milk or macaroni and cheese. Carbohydrates Starches and sugars are carbohydrates, the main source of the body's energy.