Nutrition and Health

The relationship between nutrition and diseases has long been recognized. In more recent decades the possibility of reducing the incidence of cancer, hypertension, osteoporosis and atherosclerosis by emphasizing appropriate nutrition has continued to accumulate supportive evidence. Traditionally, health care has been concerned primarily with healing the stick and helping  them to maintain health. But nowadays, more emphasis is being given on prevention and public health. Adequate nutrition is the founding f good health.

Good nutrition is considered as a basic component of health. Nutrition affects human health from birth to death. If we want to make our people healthy, nutritional needs of vulnerable groups such as infants, children, pregnant and lactating women and elderly must be met. Promotion of breastfeeding and appropriate weaning practices contribute to normal growth and development. In developing countries like India, a fair section of population does not yet have enough food to eat. The children are malnourished, emaciated and stunted.

The incidence of protein  energy malnutrition, anemia and vitamin A deficiencies are quiet among infants and pre-school children. Studies carried out in India and other countries have revealed that extra cereals and green leafy vegetables and fortified with essential vitamins and minerals can help effectively to overcome malnutrition and improve the health status of the people. The relation of nitration to health may be seen from the following view points:

Growth and Development

Good nutrition is essential for attainment of normal growth and development during fetal life and childhood. Physical growth, intellectual development, learning and behavior, all are affected by malnutrition.

Adequate nutrition is also needed in adult life for the maintenance of optimum health and efficiency. Elder people need special nutrition due to their physiological changes. Pregnant and lactating mothers require more proteins, calories and some other nutrients abortion, growth retardation and low birth weight babies.

Nutritional Deficiency Diseases

Malnutrition is directly responsible for certain specific nutritional deficiency diseases. The commonly reported ones in India are protein energy malnutrition, blindness, goiter, anemia, beri beri etc.  There is increase incidence of abortion, permaturity, stillbirth and low birth weight in malnourished mothers.


Resistance to Infectionx

Nutrition rich in proteins, vitamins and minerals prevents infections like tuberculosis. Infections in turn may aggravate malnutrition by affecting the food intake, absorption and metabolism of nutrients. So we need well balanced diet  throughout life to protect ourselves from such opportunistic infections. Good nutrition also enhances wound healing in the patients with different types of surgical operations.


For designing a balanced diet it is essential to know the  daily requirement of energy and different nutrients which varies for different age group, occupation and health status, etc. Total energy metabolism is a measure of total amount of energy required during 24 hours whether the person is resting or working. There are certain factors which influence the energy metabolism in the normal human beings. So following factors be considered while estimating the calorie requirement:

  1. Basal Metabolic Rate

BMR is the main factor which influences our nutritional requirement. It is defined as the amount of energy required to carry- on the involuntary activities of the body. Generally for an approximate determination of BMR, simple method is used, i.e. one k cal per kilogram per hour, so BMR=1 k cal *24hours. Body surface area, age, sex, sleep, climate and secretions of ductless glands are some factors affecting BMR.

  1. Weight of the person

Total metabolism includes work done in moving one’s own weight from place to place. Therefore, the heavier the individual, the more energy is required for movements.

  1. Age

Young children need more energy and protein in their growing age and adolescents require more calories than the adults.

  1. Sex

Sex also makes variation in energy requirements. The BMR of women is 6 to 10 %  lower than the man. For example, a moderate man requires 2875 k cal whereas a moderate woman needs 2225k cal.

  1. Climate and Environment

Poor environment may lead to jnfections, especially  in children. Infection and hot temperature both increases BMR, which increases our nutritional requirement. Our body must have sufficient food to make-up for heat loss. The amount of heat loss depends on the amount to work done and the temperature. This is reason that in persons living in tropical climates, the BMR is about 10% less than those living in temperate zone.

  1. Physical Activities

Activity of any kind involves an expenditure of energy in addition to the total BMR. The type of activity and total time spent in each activity determines to a large extent of body’s need of total energy. So, energy requirement depends on the type of work or occupation, i.e. a sedentary worker (man of 60 kg ) needs 2425 k cal per day, moderate worker 2875 and a heavy worker requires 38 K cal. In the USA, it has been estimated that the energy used up under different conditions of muscular activities varies which is as follows:

  1. Specific Dynamic Action of Food (SDA)

It has been found that there is 8% increases in the production of energy in the form of heat after taking food. This is not due to arry work done but it is due to stimulating effect of food on the basal metabolism. This stimulating effect is known as Specific Dynamic Action of food . It varies according to different nutrients, e.g. SDA of Carbohydrate is 5 to 6 %, of protein is 30 %, of fat is 4 % and of mixed diet is 12 %.

  1. Physiological State

There is increased demand of food in certain physiological conditions because of increased BMR. The energy requirements of woman are increased in pregnancy by 300 k cal daily throughout pregnancy, and in loctation 550 k cal extra daily during the first six months and 400 k cal during the next 6 months.

  1. Socioeconomic Factors

Nutritional status is largely affected by some socioeconomic factors like income, level of education, sanitation, family size, knowledge regarding the nutritive values of foods. Theses factors bear most directly on the quality of life and are the true determinants of nutritional status of society.

  1. Cultural Factors

Cultural factors in health and nutrition have engaged the attention of medical scientists. And sociologists. Every culture has its own customs and beliefs regarding nutritional practices. It is now widely recognized that cultural factors are deeply involved in all affairs of man including health and nutrition. Not all cultural factors are bad , some are based on centuries of trial and error and have positive values while other may be useless. Cultural influences vary widely from country to country and from region to region.

  1. Religious

Religious has a powerful influence on the food habits of the people. Hindus do not eat beef and Muslims pork. Some orthodox Hindus do not eat certain vegetables like onion, and garlic is not by Jainies and Brahman Kumari’s. Vegeterianism is given a place of honor in Hindu Socity. These food habits are know as food taboos and have a religious sanction from early days.

  1. Traditional Factors

Food is a subject of widespread traditional beliefs and customs which vary country to country and from one region to another.

Eating and drinking from common utensils is considered as a sing of brotherhood among Muslims. Hindu woman often take food left over by their husbands. In some societies, men eat first and women last. Some people do not eat unless they have taken a bath.

Pica is a common practice among pregnant woman and children in many countries. Pica is the habit of eating dirt, clay, chalk, lime stone, ashes, starch, etc. which leads to serious health problems.

  1. Food Production And Distribution

The rate of food production and distribution is another important factor influencing the nutritional status of a country. Increases food production should lead increased food consumption. It is said that there will be very little malnutrition in India today is all foods available can be equally distributed in accordance with physiological needs.