Something of a dilemma has emerged recently regarding metabolism in the healthy living community. Most people want to speed up their metabolism. Those of us who have always had a weight problem will no doubt remember watching skinny kids devouring biscuits and chocolate at break time at school, knowing that if we were to do the same we would be enormous, and subject to even more taunting. The medical community have always told us that it’s not about metabolism, but about our food and beverage intake and our physical activity, but anyone with a weight problem knows this is simply not true. There clearly are people who eat much more than plump people and never gain weight, and there are people who run every day or hit the gym several times a week and still can’t lose the beer gut. Some people just seem to have slim genes. But of course, if we diet, our body doesn’t set about losing the fat as we want it to; instead something even worse happens – it starts stocking even more fat because it thinks it’s in starvation mode, and when we come off the diet, we end up fatter than ever.
But now…things are changing. Is a fast metabolism really such great news, or are those of us heaving around a sluggish metabolism actually secretly blessed with the greatest gift nature could bestow?
What happens when we burn food fast? Our body says, I need more, so we feed it regularly. Every time we eat toxins are produced. If we have a fast metabolism and have to refuel constantly, evidence is emerging it will wear out faster. In animals, daily energy expenditure is indeed inversely related to lifespan. By reducing calorie intake while continuing to meet the body’s needs for nutrients, daily energy demands are reduced. Oxidative damage goes down (the by-product of metabolism). So the less we eat, the healthier we are. Those of us who have learnt to eat less so as not to gain weight, especially if we have been doing this from childhood, are in the running for a longer, healthier life.
So what of exercise, which causes our metabolism to work faster? How come exercise is also linked to longevity? The point here is the free radicals produced during exercise are quickly eliminated by the body, with the added bonus that the body produces antioxidant enzymes right afterwards, which means the body is better at protecting itself all day long.
Calorie restriction diets make us lose weight at first but – as all dieters know – over time, our body adjusts its metabolism to fit the lower calorie intake, and we stop losing weight. Contrary to what the yo-yo dieters have always thought, this is good! Keep calorie intake low permanently and avoid chronic illness and accelerated aging.
So managed correctly, a slow metabolism is a fabulous gift. And those of us who were born with a fast one can adjust our metabolism to slow down, so that life itself slows down, giving us more years in better health.
Obesity is to be avoided at all costs; instead let us use nature’s gift of a slow metabolism to train our body to function with less. Exercise-induced rises in energy expenditure are still associated with increased, not decreased, longevity. Although exercise increases free radical production in the short-term, the body adapts to these free radicals. When it does, it becomes even better at protecting itself against their damaging effects by producing more cell-protective antioxidant enzymes.