Amazingly, given enough calories, the human body is capable of production the most of the thousands of the chemical nutrients that it needs to sustain life. Several nutrients, however, aren’t made by the body and are therefore called essential. The essential nutrients are divided into six general categories: water, proteins, carbohydrates, fats, vitamins, and minerals. Adequate intake of fiber is also important in the normal functioning of the intestines and prevention of disease. This article examines the essential nutrients, their sources, and their role in health and disease. Background – The human body is made up of thousands of different chemicals.
Amazingly, provided with enough calories, the body is capable of production nearly all its needed nutrients. There are, however, some 45 or so nutrients that the human body is incapable of production. These nutritional elements are called essential because it’s vital for humans to incorporate them in their diets. The essential nutrients can be divided into six general categories: water, proteins, carbohydrates, fats, vitamins, and minerals. Strictly speaking, fiber isn’t an essential nutrient, but it’s also extremely important in prevention of certain diseases. Water – Approximately 60% of the adult human body is made up of water. Almost all the life sustaining chemical reactions require an aqueous environment.
Water also functions as the environment wherein water soluble foodstuff is absorbed in the intestines and the waste products are eliminated in urine. Another essential role of water is to maintain temperature of the body through evaporation, as in sweating. Severe dehydration will result in cardiovascular collapse and death. And on the other hand, water toxicity is also possible, leading to dilution of important electrolytes that can lead to erratic heart rhythm and death. The estimated water requirement of an average adult is two litre per day. Calorie Sources – There are 3 sources of caloric energy: proteins, carbohydrates, and fats.
Proteins make up the structural foundation of the cells, tissues, and organs. As a source of calories, proteins provide four Calories per gram. Proteins are made up of smaller building blocks called amino acids. Twenty amino acids make up all the human proteins. Of those twenty amino acids, the body can produce only 12, but 8 must be incorporated into the diet. These amino acids are lysine, leucine, isoleucine, methionine, phenylalanine, threonine, tryptophan, and valine. Any source of protein is sufficient to provide the body with the required amino acids, although animal proteins are richer in essential amino acids than cereal or vegetable sources. Protein deficiency is most likely more common than many people would believe, even in the developed country. Severe protein deficiency, rare in the developed country, results in growth retardation, anemia, and swelling of the body in small children and muscle wasting and weakened immunity in adults.