The Importance of Metabolism

The Importance of Metabolism

By Julie Alvira, MD, MBA

The truth is, we never think about the importance of the term metabolism. We have heard it on various occasions. Everybody mentions that one needs to keep their metabolism going for weight loss and eat every three to four hours, right? But, do we actually know what it means?


What is Metabolism?

Metabolism is all the chemical reactions happening in the body all the time that make us exist. These reactions can be classified in two major groups:

Catabolism: involves the breaking of molecules for energy.

Anabolism: the synthesis of all the compounds that cells need.

During these types of reactions, the cells break down nutrients to produce energy that our bodies use in different ways. You might think that the body uses energy only when we are in movement. But, no. Even when we are at rest, the body uses this energy for different processes such as: breathing, circulating blood, adjusting hormone levels, and much more. Such processes use a number of calories (energy units) that are known as the basal metabolic rate (BMR) or what we commonly call metabolism.

Metabolism and Calories

There are several factors that affect metabolism such as:

  • Body Composition and Muscle Mass: People who have more muscle tissue in their bodies will burn more calories (even at rest) than those with higher fat content. It happens because the muscle requires more energy to function. Resistance exercises using weights are excellent for building muscle mass.
  • Gender: Men have more muscle mass than women compared to same age and weight.
  • Age: The older we get, the slower our metabolism becomes.
  • Genetics: It has been shown that genes contribute to the rapidity of metabolism.

Why metabolism slows as we age?

In a previous article I talked about anti-aging medicine, which explains some aspects of what happens as we age. Taking that into consideration, one aspect to mention is the slowing of BMR. Everything is joined together because as lean muscle mass begins to decrease in relation to total body mass, the BMR does as well. Having said that, it is very important to maintain a good exercise regimen of strength training in combination with cardiovascular exercise for the heart. Strength training helps us maintain or develop lean muscle mass. It’s good advice to also maintain a healthy eating program to help with the development and maintenance of such lean muscle and fight the accumulation of belly fat.

Metabolism and Weight Loss

Individuals who want to lose weight should not fast. This is more important as we age. If you did it when you were in your 20s, well this is not the time to start again. As I mentioned above, if you cut the amount of calories, nutrients and protein your body needs, your lean muscle starts to break down to compensate. The body uses the resources at hand, so keep those nutrients coming in every three to four hours. Also, you need to consider that the metabolic rate goes down 2% or more per decade.

Strategies to stimulate the metabolism

  • Regular exercise: Either endurance (helps to increase muscle and delay its loss with age and accumulation of fat) or aerobic (dancing, swimming, walking, etc…) help keep the person active and burn more calories.
  • Hydration: Studies have shown that ingesting about two glasses of water before each meal helps to stimulate metabolism.
  • Food and beverages: Green tea, caffeine, yogurt, spicy foods, whey protein, salmon, and add snacks during the day (eat every three to four hours).

Remember, a good combination to follow is to eat healthy, get regular exercise, practice stress releasing techniques, smile, and be grateful.

Julie Alvira, M.D., MBA Healthcare Management. Health & Wellness consulting. Coaching services only for women in the areas of wellness, nutrition, fitness, addictions recovery, and wellness in the workplace to reduce burnouts. “I like to focus on women and helping them get into a healthier lifestyle.” You can reach Julie via