How a person defines the word “metabolism” may depend on whether you ask a biologist or a dietician. From a biological standpoint, metabolism is a combination of biochemical processes your body uses to convert food into energy. These metabolic processes include breathing, eating and digesting food, the delivery of nutrients to your cells through the blood, the use of energy by your muscles, nerves and cells, and finally, the elimination of waste products from your body.
However, when most people refer to metabolism, they are referencing the rate at which our bodies convert food into energy (calories) and then use the energy to perform essential and non-essential daily functions. The rate at which we burn calories or energy is called metabolic rate. Whatever the definition used, metabolism is a vital process for all living things.
Your metabolic rate might change from day to day depending on your activity level, but your basal metabolic rate stays fairly steady. Your basal metabolic rate (BMR) is the number of calories needed to fuel your body’s essential functions, like breathing and circulating blood. Basal metabolic rate is the most significant component of your total metabolic rate. This value can actually be calculated using the following formula – the answer will be the number of calories your body needs for basic functioning:
Men: BMR = 88.362 + (13.397 x weight in kg) + (4.799 x height in cm) – (5.677 x age in years)
Women: BMR = 447.593 + (9.247 x weight in kg) + (3.098 x height in cm) – (4.330 x age in years)
When evaluating the concept of weight loss or weight gain, the basal metabolic rate is a relatively fixed value, so the only generally adjustable value is based on how much you eat and exercise. Once you have your BMR, you can find out your total metabolic rate. Your total metabolism or metabolic rate is a combination of your BMR and the calories used for processes like eating, exercise and other daily movements.
So, for example, you could use a fitness/diet tracker to track the number of calories you burn in a single day from exercise and non-exercise movement. Adding this number to your basal metabolic rate will give you your total metabolic rate – the number of calories your body used in the day. By comparing it to the number of calories you consumed, you can determine whether you are in a caloric excess or deficiency.
If you can learn how to manage and maintain a healthy metabolism on a regular basis, weight loss and weight maintenance will be easier.
While the basal metabolic rate is relatively fixed, there are some things that can affect it. Some medications can affect your metabolism, either dangerously speeding it up or slowing it down. Some health conditions such as thyroid disorders are known to affect the basal metabolic rate. Weight loss, especially when it’s rapid, actually slows your metabolism because it takes less energy for your body to function at a lower weight. So, as you lose weight, you need to take in fewer calories or get more physical activity to burn more calories and keep losing pounds. And finally, age can slow your metabolism. In general, as you age, you gain fat and lose muscle. Some people also become less active as they get older. However, you can do the opposite and take on more physical activity to make up for your slower metabolism.
There are some things that you can change about your total metabolic rate and some things that you can’t. For example, you can’t change your age or your gender. But there are some changes you can make that will boost your metabolism and help you lose weight. These include daily exercise, increasing your daily movement, adding muscle and eating the right amount of calories.
Your metabolism will change slightly from day to day. But if you can learn how to manage and maintain a healthy metabolism on a regular basis, weight loss and weight maintenance will be easier.