5 Factors Affecting Metabolism

Metabolism is the rate at which our bodies burn calories.  Basal Metabolic Rate, or BMR is the number of calories our body requires to live each day, just to carry out our bodily functions.  It does not include the 60 minute weight workout, or the ten mile run that you went on in the morning.

We’ve all looked at our thin co-workers or friends and wondered what they did to deserve such a good metabolism.  It’s no secret some can eat whatever they want and never gain an ounce, while some of us can merely glance at an item of food with lust in our eyes and we and gain weight.  Just as with risk factors for hypertension and cardiac conditions, some factors affecting metabolism are under our control while others are not. 

The goal is to speed up our metabolism when trying to lose weight so our body will burn more calories in a shorter time.

Body Size         This is sort of a no brainer; a bigger body has more cells to maintain therefore larger people have a faster metabolism. The extra weight that a large person carries around also increases metabolism due to the body’s increased effort in moving the body around. 

Body Composition        “Composition” refers to the amount of bodyweight that is fat and the amount that is muscle.  Fat takes up more space and uses less calories, while muscle uses up less space and uses more calories.  Therefore, the more muscle you have, the higher your metabolism. 

Sex (no not that kind of sex)     The BMR of males tends to be higher than females due to hormones such as testosterone.  Also, men tend to carry more muscle mass, causing increased caloric requirements. Note that BMR is based on other requirements as well, so this is just a generalization.

Age   Our metabolism slows as we age; some say as much as 2% for every decade after 20.  It is part of the natural process of aging and is true for men and women.  The fat percent increases while the amount of muscle decreases, possibly due to hormonal changes.  Another thing that happens as we age is that we have a tendency to become less active. This factor is one that we have control over.

Diet - Eating and digesting food requires a small amount of energy, so eating a little more often can help increase BMR.  For example, eating 5-6 times a day rather than the standard three meals help increase your metabolism by as much as 20%. 

This is neither a comprehensive list, nor an in depth study of each factor.  Other factors will be discussed at a later date. 

The three factors that we can control, based simply on this article, are our body composition, activity level, and how many times a day we eat.