Why does your metabolic rate slow down as you age?

To answer the question why metabolic rate drops as we grow older, we have to have a clear understanding as to what is meant by ‘metabolic rate’. Only then can we understand why it slackens with age. Metabolic rate is the number of calories (measure of energy) that our body burns or uses just to stay alive and perform simple body functions.

Interestingly, even when are resting, the metabolic rate is still at work. Traditional thinkers relate slowing down of metabolic rate as an after-effect of loss of muscles, which is a normal phenomenon of the aging process. The truth of the matter, however, is different. Loss of muscle mass due to aging is not the only thing that affects metabolic rate of the body.

Recent research has shown that metabolic rate can slow down irrespective of the fact that there is some muscle loss. Thus, a young man who is physically active can have a higher metabolic rate though he has the same muscle mass as an older individual.

There could be two reasons as to why metabolic rate slows down as we age. Firstly, there is a direct link between the amount of exercise and your own metabolic rate. That is, the more physical exercise you do, the higher your metabolic rate. As we age, we tend to spend less time in physical exercises and this could be attributed to resultant drop in metabolic rate.

Secondly, metabolic rate is also directly proportional to the amount of calories you take per day. This means that the more calories you have in your diet in the day, the higher your metabolic rate. A lower metabolic rate in older people, though they are physically active, could be due to the fact that they eat less than younger people.

This fact was brought to light by a team of researchers working in the University of Colorado who compared the metabolic rate of some physically active and inactive men, of the same age.

With regard to the relationship of muscle mass and metabolic rate, it was found that older people, irrespective of whether they are physically active or inactive, had lower metabolic rate than younger people. While older men burnt about 64 to 68 calories per hour, the younger men burnt anywhere between 72 to 77 calories per hour.

Interestingly, when younger men and older men were doing the same amount of physical exercises, or eating the same amount of calories, the basal metabolic rate remain unaltered.

Similar research has also been done with regard to women. It has been found that when pre- and postmenopausal women were compared, after adjusting for age-related muscle loss, metabolic rate was lower by approx. 10% in the postmenopausal group who are physically inactive. Yet, there was no difference in the metabolic rate between pre and postmenopausal women who were physically active.

In conclusion, it can be said that slowing or dropping of metabolic rate is not an inevitable result of aging. It has everything to do with your diet and the way of life which you lead. You can control the drop of metabolic rate by taking the proper nutritious diet and combining it with adequate physical exercise.

Bert Colijn
Internet Affiliate Marketer