Introduction To Science Of Dietetics

While the subject of dietetics is meant for requirements of students and practitioners of medicine, it is also useful to all those who desire to acquire some knowledge about the foods we eat daily and the nutrition it provides. With number of patented and proprietary foods available in the market at considerably higher prices, the knowledge of the subject of dietetics will certainly enable readers to make the right choices and derive value for money spent on branded food items. Moreover, the incidences of cardiovascular diseases and diabetics are also in increase in the younger generation and from this point of view as well, the knowledge of dietetics will help to reduce the occurrences of these types diseases as they are lifestyle driven disorders.

We consume food or in scientific term diet to survive and get energy for carrying out our day to day activities. The principle constituents of diet are carbohydrate, fat and proteins. Apart from these, a well balanced diet also should contain vitamins, minerals and fibers. Our body produces required energy in the form of calories generated by the food that we eat. Each gram of protein or carbohydrate produces 4 calories, while one gram of fat produces 9 calories.
Proteins are the building blocks of our body and they repair the wear and tear in the body. Minimum daily requirement of protein is 0.5 gm of first class protein per Kg of body weight. First class protein has high biological value (source being animal such as meat, milk, eggs etc). For vegetarians this requirement is 1.0 gm of protein per Kg of body weight. Vegetarians should always eat variety foods in combination to ensure optimum supply of required protein. Requirement of protein for pregnant ladies, lactating mothers and growing children is double the requirement for normal persons.

Ideally 50 % of energy should come from carbohydrates, 20% from fats and 30% from proteins. Maintenance of this ideal ratio is imperative to spare protein for growth and or repairs of body due to wear and tear.
Requirement of calories for people with different stature and age groups are different, change from males to females and depend on the level of activity of the person. On average 1300-1500 calories are needed on resting basis. Very light physical activity requires 1.5 times the resting calories, light physical activity requires 2.5 times the resting calories, moderate physical activity requires 5.5 the resting calories, heavy physical activity needs 7 times the resting calories. On average young men require 1.6 times the resting calories and young women require 1.55 times the resting calories.

Foods rich in carbohydrates are cereals, grains, potatoes, fruits and vegetables etc. Protein rich foods are milk and dairy products, meat, eggs, fish and sea foods, legumes and beans etc. Foods rich in fats are dairy products (excluding fat free products or low fat products), dry fruits, cooking oils, butter, meat, fish and sea foods etc.
Apart from protein, fat and carbohydrate, our body also requires vitamins and minerals. Vitamins content of fruits and green vegetables, dairy products, dry fruits and sea foods are enough to take care of our daily requirements. Milk, vegetables, cereals, grains are also good sources of minerals that our body require.
A detailed knowledge in the science of dietetics enables to lead a healthy lifestyle by prevention of lifestyle related diseases from occurring.