Metabolism is similar to the engine of a car. It's the energy process that burns the fuel and converts it into energy. This is necessary for the car and the body. So naturally when the metabolism begins to slow down, some kinks in the system are bound to occur -- weight gain, for instance. But the good news is that if you can regulate the factors that control metabolism -- muscle mass, for example -- then you can regulate your metabolism.
Hormones do more than make you a little crazy around that time of the month. They also influence metabolism. The thyroid gland is specifically responsible for producing the hormones that can increase or decrease your metabolism. According to the American College of Sports Medicine, these hormones regulate how much oxygen your body uses and how many calories will be burned. With age, however, the thyroid’s hormone production rate begins to diminish, which slows down the metabolism. According to the ACSM, this begins around age 40 for most women.
Although it may seem like you’re doing yourself a favor by reducing your caloric intake, in some respects you’re not. Sure, you may be able to lose weight by reducing your calories, but this can also slow down your metabolism. Why is this? According to the ACSM, reducing your caloric intake signals the body to save calories, not burn them. In other words, your body thinks you’re starving, and it’s attempting to save every bit of energy that it can. To compensate, your metabolism slows down. So how much should you be eating? The ACSM suggests that women eat about 1,200 calories a day, even if you're attempting to lose weight.
Certain foods can influence your metabolic rate by speeding it up or slowing it down. Carbohydrates such as white bread and pasta are mainly composed of simple sugars. Since most of the complex carbs have been removed from these foods, they’re much easier to break down. The consequence, however, is that they don’t require much energy for digestion. So they don’t challenge the body. As a result of eating these types of foods -- simple-sugar carbs -- the metabolism slows down. Fatty foods have a similar affect, according to Fitday. The body tends to store the fat, instead of breaking it down right away, which also slows the metabolism.
You may want to reconsider removing those strength training exercises from your exercise routine. Your body composition -- particularly how much muscle you have-- plays a large part in your metabolism. Generally, the more muscle you have, the higher your metabolism. The lower your muscle mass, the lower your metabolism. Why is this? Muscles require a great deal of energy to work properly, so they burn a lot of calories. So, if you have fewer muscles, you'll burn fewer calories. With age, muscle loss tends to increase. The ACSM states that people's metabolic rate tends to drop 2 percent to 3 percent each year after age 20. Typically, this decrease is because of muscle loss. So, maintain your muscle mass, ladies.
Based in Atlanta, Mya Passmore has been writing since 2010, covering health and business topics. She holds a Bachelor of Science in exercise science from George Washington University.