Food

Food

Foods are those chemical substances which an individual takes, digests, assimilates and provides the nutritive requirements of an individual to maintain growth and physical well being. Food supply energy for production of heat and for all types of activities. It essential for growth of human body. It essential for the repair of the daily wear and tear. Protects the body from various types of diseases. In general way, it is involved in the functioning of the body processes.

Caloric intake and distribution

The calotic value of the dietary intake must be approximately equal to the energy expended if body weight is to be maintained. In addition to the 2000 k cal/d necessary to meet basal needs, 500-2500 kcal/d are required to meet the energy demands of daily activities. The distribution of teh calories among carbohydrate, protein,and fat is determined partly by physiologic factors and partly by teste and economic considerations.

Protein :A daily protein intake of 1 g/kg body weight to supply the eight nutritionally essential amino acids and other amino acids is desirable. The source  of the protein is also impotent. The animal proteins of meat, fish, diary products, and eggs, contain amino acids in approximately the proportions required for protein synthesis and other uses.20 to 30 grams of the body proteins are degraded and used to produce other body chemicals daily. Therefore all cells must continue to from new proteins to take the place of those that are being destroyed, and a supply of protein is needed in the diet for this purpose.An average person of protein is needed in the diet for this purpose. An average person can maintain normal stores of protein, provide the daily intake is above 30-50 grams. Therefore, individuals in economically disadvantaged countries who consume cornmeal as the principal source of protein sometimes develop the protein-deficiency syndrome called workmanship which consists of failure to grow, lethargy, depressed mentality, and edema caused by low plasma protein concentration.        
   
Fat : Fat is the most compact form of food, since it supplies 9.3 kcal/gm. However, often it is also the most expensive.Indeed,internationally there is a reasonably good positive correlation between fat intake and standard of living. In the past, Western diets have contained large amounts.The evidence indicating that a high unsaturated/saturated fat ratio in the diet is of value in the prevention of atherosclerosis and the current interest in preventing obesity may change this. In central and south American Indian communities where corn is the dietary staple, adults live without ill effects for years on a very low fat intake. Therefore, provided that the needs for essential fatty acids are met, a low-fat intake does not seem to be harmful, and a diet low in saturated fats is desirable.

Milk

Milk is an ideal food. It is unique in nutritive  value and contains all the food factors of a well balanced diet required for human body.It is easily digestible, absorb able and assimilable. Skimmed milk powder is devoid of fat and fat soluble vitamins but a good source of  protein, calcium and water soluble vitamins. Cow's milk is to be suitably changed to make it comparable to mothers milk and to make a substitute drink for young baby, even a new one. The insoluble carcinogen of cow's milk must be reduced to the level as  present in human milk, the amount of lactose must be increased to the right proportion and the resulting mixture must be pasteurized.

Energy balance

The endocrine system, like the nervous system, adjust and correlates the activities of the various body system, making them appropriate to the changing demands of the external and internal environment. Endocrine integration is brought about by chemical signals secreted by ductless glands and transported in the circulation to target cells. Some of the hormones are amines, and other are amino acids, polypeptides, proteins, or steroids. Only about 27 per cent of the energy ingested normally reaches the functional sys-
tens of the cells, and much of this is eventually converted to heat, Which is generated as a result of protein metabolism, muscle activity, and activities of the various organs and tissues of the body. Excess energy intake is stored mainly as fat where as a deficit energy expenditure eventually equals energy intake or death occurs. In athletes and laborers, energy expenditure for the high level of muscle activity may be as high as 6000 to 7000 calories per day, compared with only about 2000 calories per day for sedentary
individuals.