Are calories necessary for health and fitness?

What a question to ask, in this day and age!! Of course, they are.

To answer this, do we need to know what are calories, how much do we need, what foods give us calories and how much? What are the changes during the life of an individual with respect to calories and food?

So, let us see how the knowledge of calories can be used to improve the health of  you and your family.

Here are the basics:

Calories give us energy

Physical activity requires energy and the body uses the energy available from the food consumed for all the internal and external activities. The internal activities are those that are happening in the body, involuntarily.

Calorie-free foods in the diet

The beating of the heart to pump blood for circulation, the activities related to digestion, metabolism and waste disposal, involving the other organs like liver, intestines, kidneys, pancreas and gall bladder, the skin and the nervous system, all these are in constant working condition, needing energy from food.

This is also called BMR (Basal Metabolic Rate). It is high at infancy, childhood and adolescence as these are rapid growth periods. It gradually, decreases with age and is lowest in the elderly especially when they become immobile.

What’s a kilo calorie?

It is the amount of heat required to raise the temperature of one Kg. of water by one degree centigrade. It is a measure   expressing the energy and heat potential of food.

Further all the physical activities need more energy. It goes without saying that as the physical activity increases, so does the need for extra calories from food.

When the energy needs of an individual are met completely, without excess or less calories, he should be well balanced and in good health.

Now that you know what is a calorie and why it is important, we’ll move on to how much you need.

Six diet rules you must follow to lose weight

The guideline is from ICMR (Indian Council of Medical Research). The RDA (Recommended Daily Allowances) for calories, for Indians is given below.

Source: The Nutritive Value of Indian Foods, Gopalan

Group Particulars Body weight

in kg

Net energy


Man Sedentary work 60 2425
Moderate work 2875
Heavy work 3800
Woman Sedentary work 50 1875
Moderate work 2225
Heavy work 2925
Pregnant woman 50 +300
Lactation 0 to 6 months +550
6 to 12 months +400
Infants 0 to 6 months 5.4 108/Kg
6 to 12 months 8.6 98/Kg
Children 1 to 3 years 12.2 1240
4 to 6 years 19 1690
7 to 9 years 26.9 1950
Boys 10 to 12 years 35.4 2190
Girls 31.5 1970
Boys 13 to 15 years 47.8 2450
Girls 46.7 2060
Boys 16 to 18 years 57.1 2640
Girls 49.9 2060

How to achieve your calorie requirement in terms of foods will be explained next. Till then, just eat in moderation. !

(To be continued)

Malathi Mohan

Ms. Malathi Mohan is Dean, Academy of Fitness Management, FitnessOne, Chennai.

This is the second of a five-part series on calories by nutrition expert Malathi Mohan.

Click here to read last week’s article: Why count calories