On any given day I get at least one client who walks into my clinic and says he (or she) is 40 years old, has maintained the same levels of physical activity for the past 10 years but of late has been putting on some weight. They’re not eating more nor have they reduced their activity level so what is going on?
The answer to this complex sounding question is actually quite simple –
as we grow older, we need fewer calories.
The reason for this is that our muscle mass gradually decreases. Have you seen the upper arm of someone who is 60 or 70 years old? The muscles just hang on the bone – thin and weak. This happens because the internal mass has long been converted into energy and no new mass added to it. As we grow older, the mechanism that adds muscles slows down. It is actually a part of the slowing down process within our body. It is something that is genetically coded and pre-programmed to happen. To an extent you can combat it by undertaking body building exercises but even then, the amount of muscle mass your body will add will be on a diminishing scale. Also, as you get older, the bone density decreases as well. This makes any body building exercises quite dangerous.
Before we understand what happens within us as we grow older, you need to know that muscle tissue burns more calories than fat. So as you grow older, you have less muscle and therefore less calorie burning capacity i.e. you need lesser calories as you grow older.
If you keep eating the same amount of food as you did for the past ten years then those extra calories will turn into extra pounds.
For example, if you are say 5’4″, 130 pounds, and you engage in a 1 mile jog every day, other things remaining the same, you probably need around 1,900 calories at age 40. By age 60, to maintain the same weight of 130 pounds without any reduction in the 1 mile jog, you will need between 1,600 to 1,700 calories. Please note that these are just rough estimates. I haven’t taken into account individual differences in other activities that you might be doing, your race and genetic make-up and so on. Anyway, all that is beside the point.
The point is that you need less calories as you grow older – roughly 20 calories less per year after the age of 40.
So what should you be doing? Either you should eat less or exercise more. As you grow older, the latter not only becomes increasingly difficult, at some point in time, there is a danger that the bones might break (due to reduced bone density in old age). So the answer then is, eat less as you grow older. If you give up any particular exercise or activity you used to do, then you will need to make further adjustments in the quantity and type of food you eat.
Read more about healthy eating for older people.