Have you ever asked yourself why some people can eat whatever they want and be skinny while others gain weight? You’ve likely been told they have a “faster” metabolism that allows them to indulge. Let’s explore these concepts.

What is the Metabolism

In simple terms, our metabolism is the process by which we convert the food we eat into usable energy. It powers essential bodily functions like breathing and blinking. 

The way most people refer to a metabolism is actually incorrect. For instance if a person truly had a “slow” metabolism then the body wouldn’t be able to extract energy from the food and simply pass it through the body. This would result in you losing weight. 

What people are actually referring to in regards to metabolism is the basal metabolic rate or BMR. 

What is the Basal Metabolic Rate (BMR)

Your BMR is the minimum amount of energy your body needs to survive. For instance if you were to do nothing your body still needs to perform bodily functions like breathing, blinking, circulating blood, etc.

In general the bigger you are the more calories you’ll burn. This is because taller/broader people have larger surface areas and it requires more energy to maintain them. 

Differentiating Metabolism and Thermic Effect on Food

As we said, the Basal Metabolic Rate are the calories your body burns while you are idle. BMR plays a vital role in your Total Daily Energy Expenditure (TDEE) to help your metabolism work as it should.

The rise in obesity in the United States isn’t a result of millions of people with slow metabolisms. However, our environment is much different. High calorie, processed foods are in abundance and our bodies don’t have many stressors. Most people work office jobs that require them to be sitting for extended periods of time in heated/air conditioned rooms. 

Thermic Effect of Food (TEF)

Thermic Effect of Food is the calories your body needs for it to be able to digest food by energy conversion. Whenever we eat, our bodies burn calories to digest the food. And for us to utilize the calories from the foods we eat, it needs to undergo a digestion process to absorb nutrients.

Additionally, our bodies need to be at a stable temperature for it to produce heat, since different macronutrients in food also have different levels of thermic effect.

For example, protein has the highest thermic effect of them all with a total of 15 to 25 percent of the calories. Carbohydrates on the other hand, have a lower number that ranges from 5 to 10 percent. And then we have fats which has a total of 5 percent.

This is why high calorie processed foods like Fast Food isn’t good for you.

“Special Foods” that Cause the Thermic Effect

People are often misled to believe that you can get a thermic effect by eating a particular food. When in reality, all foods have a thermic effect.

It’s been shown that substances like caffeine and chilli do have a small effect, but not enough to be a shortcut for weight loss. 


When most folks are talking about metabolism they often confuse it with BMR which is the rate at which you use the calories you consume. Taller people tend to have a higher BMR due to the larger surface area for bodily functions.

With the exception of certain endocrine disorders like hypothyroidism and Cushing’s Syndrome, you shouldn’t blame a “slow” metabolism for your weight gain issues.

If you’re finding that it’s hard to lose weight, it’s likely because your diet is poor and you don’t have a high enough exercise level. There isn’t a magic pill to take or food to eat that will speed it up.