Metabolism, How Does It Work?
When we think of metabolism we think of it as being
"how fast our we burn the calories we eat, but it’s far more than that. Metabolism is the sum of chemical processes that occur within our body by which our cells are created, maintained, and broken down, and by which energy is produced.
So, our metabolism is responsible for building and maintaining all the cells in our entire bodies (including muscle and bone tissue), for determining where and how much fat gets stored or burned, and for turning food into fuel for our cells.
We want our metabolism to be fast because when the cells of our body are created and able to turn over more efficiently, we’re healthier. Keeping our metabolism high allows us to maintain healthy levels of muscle mass, body fat, and bone density throughout our lives.
Your metabolism is under your control. Yes, you may be genetically predisposed to have a slightly slower metabolism than your skinny friend—but you can easily speed up your metabolism by working out regularly and making sure to eat enough. Your metabolism is far more dependent on your exercise and eating habits than on your genetics.
Wait, did I just say eating enough? Yes, when you eat too few calories or fast regularly, you send your body into starvation mode. Your metabolism will slow down to conserve energy, and your body will burn proteins within your muscle tissue as an energy source. This reduces your muscle mass, decreases your energy and strength, and slows your metabolism further.
Many older adults eat less because they feel that their caloric needs have changed, and their appetites have decreased. This is the direct effect of their decreased activity level resulting in slowed metabolism—not of the natural aging process. And unfortunately, not eating enough means these adults aren’t taking in the nutrients and calories their bodies need to maintain their metabolism, muscle mass, and bone tissue.