The human body is really a living machine and like every other machine. The living machine obliges fuel to supply with vitality. The fuel gave by the nourishment we eat. Yet, we know the amount we have to remain sound? The vitality estimation of the nourishment is generally measured in calories. Calorie is the measure of warmth required to raise the temperature of 1 kg of water by 1 degree c. the quantity of calories that individuals require every day changes. This relies on upon the exercises of the individuals who take part in for instance, individuals will require a greater number of calories to stand as opposed to sit, individuals oblige more to keep running than to walk, and so on gave by nourishment vitality as three sorts of synthetic substances. They are sugars, proteins and fats. Starches give 8.8 calories for every gram (CAL/gm) vitality, protein 4.0 CAL/gram and fat 8.0 CAL/gm. every nourishment contains distinctive extents of substances.These three concoction substance is exceptionally essential for the body remain sound.