Metabolism is a hot-button word in aging and weight management. I’m sure you’ve heard that people either have a fast or a slow metabolism, or so that’s what we’ve been taught. However, metabolism is more complex than just being fast or slow.
Metabolism is the process of breaking down food into energy. Our body’s metabolism fuels its every function. It keeps our heart pumping, our lungs breathing, our digestion flowing, and many other processes. Metabolism is the body’s way of “keeping the lights on” and keeping us alive. There are many biological cascades involved in metabolism and if you’re interested in learning more about them, check out this video.
Slow vs. Fast
The difference between a “slow” metabolism and a “fast” metabolism is how many nutrients our bodies need to burn to keep us alive. A “slow” metabolism needs less nutrients to produce the same amount of energy than someone with a “fast” metabolism. This explains why some people appear to be able to eat whatever they want and never gain weight, and others seem to easily gain weight. But just because you may have a “slower” metabolism than someone else, doesn’t mean your natural metabolic rate can’t improve. Ways to speed up your metabolism include building muscle mass and increasing your physical activity. Certain foods, like spicy foods or green tea, only increase metabolism to a very minor extent (maybe a few calories).
Genetics are the main determinant of our metabolic rates, but we can boost metabolism by increasing lean muscle mass. Muscle tissue takes more energy to maintain than fat, or adipose, tissue. Having more muscle tissue naturally makes your body burn more energy or have a faster metabolism. Our muscle mass decreases as we age, and this contributes to a slower metabolic rate. You can counteract this process by picking up the weights to help lessen this decline.
It’s true that you burn more calories during vigorous exercise, but you can continue to burn extra calories after you’re done exercising as well. This effect can last an hour or so after exercising, but eventually our metabolism will go back to its resting rate. While it’s true that our metabolism is slower than when we were younger, a lot of mid-life weight gain happens because we become less active.
Throughout the aging process our natural metabolism slows down, and our bodies become less efficient. Maintaining a lean, muscular body will burn more calories to function than someone of the same weight with a higher percentage of body fat. Besides building muscle, increasing your daily activity can boost your metabolism during exercise and for about an hour afterwards.