These eight essential amino acids must be present in sufficient quantities in our food for us to enjoy good health. Water makes up a large part of our foods. Although it yields no energy, for many reasons water is an essential element for life. Approximately 60 percent of body weight is water. Because the four nutrients discussed above - carbohydrates, fats, proteins, and water make up the largest portion of any foodstuff by weight, they are often referred to as macronutrients.
Vitamins are organic compounds that are synthesized for the most part only by plants and bacteria.
Thus, our supply of vitamins must come from plant foods and our own bowel bacteria. Vita means life, and, as the name indicates, vitamins are essential for our existence. Without adequate amounts, disease can develop. Minerals are also micronutrients, but they come from inorganic matter, primarily the earth. Their presence in adequate amounts in our foods is also essential for our good health.