8 metabolism myths debunked

8 metabolism myths debunked

Most of us who are concerned about our health and weight are familiar with the term metabolism. Learning more about this complicated process can help you understand the steps to better weight management.

What is metabolism?

Metabolism can generally be broken down into two processes: catabolism and anabolism.

  • Catabolism is the process that breaks down compounds or molecules (typically from food) to release energy. This energy is used to fuel body processes such as movement.
  • Anabolism is the building of complex compounds or molecules from simpler compounds. This process usually requires energy. Anabolism allows your body to maintain cells and build new ones.

What you weigh is mostly the result of your catabolism minus your anabolism — the amount of energy (food) you put into your body minus the amount of energy your body uses.

Now that we understand metabolism a bit better, let’s separate some metabolism myths from the facts.

  1. Slender people have higher metabolism rates than overweight people. This is a pretty big myth. In fact, the bodies of larger people require more energy than smaller people. That means, as you lose weight, you’ll need less food to fuel your body. And after you lose weight, if you return to old eating and exercise habits, the weight will come back because you’re providing more fuel (food) than your body needs. So, keep active to keep those pounds at bay.
  2. Eating a lot less food slows your metabolism. This is true and not a good idea. Eating a lot less food can kick your body into what’s commonly known as starvation mode — your metabolism slows so you use less energy and burn fewer calories. Your body may also drop muscle mass to conserve energy. Starvation mode tends to leave you feeling hungrier and sluggish. Food cravings can lead you to eat more and undo weight loss efforts. So, starvation is a bad way to lose weight.
  3. Your metabolism slows as you age. This is a myth. In reality, your metabolism only slows if you become less active. Your best metabolism boosting plan is to stay active!
  4. Exercise boosts your metabolism. The calories you burn while exercising vary depending on the intensity, but it’s true – exercise does burn calories! When it comes to boosting metabolism, the key is to choose fitness activities that build muscle.You don’t have to be a body builder to reap the benefits of a higher metabolism. Strength training can boost your metabolism as added muscle boosts your resting metabolism. High-intensity interval training has a double benefit. It burns calories during your activity and also boosts your calorie burn after your workout.Actually, most any physical activity, even a housekeeping chore, is better than sitting on the couch. A word of caution: Don’t overestimate how many calories you burn during your physical activities. If you reward yourself for a two-mile walk with a cookie, you can negate the benefits.That cookie we mentioned? You have to walk for more than a half hour to burn those calories!
  5. Multiple small meals during the day are better for metabolism than three square meals. Studies show multiple small meals do not boost metabolism, so this is a myth. That said, this approach can stave off between-meal hunger, so some people have success losing weight this way. However, without good portion control, you can end up eating more.
  6. Turning down the thermostat can turn up your metabolism. This is a fact! When it’s cool, your body turns up your internal thermostat and burns extra calories to warm you up. A temperature around 66 degrees for a couple of hours can boost your metabolism. If you, and those with you, are comfortable, add more cool time for more impact on your metabolism. Keep in mind, eating more food can undo your metabolism boost.
  7. Eating spicy food boosts your metabolism. If you like spicy foods, we have a bit of good news: Spicy foods such as chili peppers do boost your metabolism…a little. Spicy foods can spike a person’s body heat, which takes energy to produce. This process can also enhance fat breakdown. You’ll need to eat at least a tenth of a chili pepper regularly to get the effect.
  8. Drinking green tea boosts your metabolism. This one is true. Green tea’s antioxidants and caffeine can increase the calories your body burns. When choosing your green tea, look for higher antioxidant and caffeine levels.

If you already consume lots of caffeine, green tea’s effect will likely be limited.

Bonus metabolism tips

Now that we’ve clarified some myths and facts about metabolism, here are some additional effective steps you can take to increase your metabolism.

  • Get an appropriate amount of sleep. For most adults, about 7 to 8 hours is recommended. Children usually need more.
  • Drink plenty of water throughout the day.
  • Cut heavily processed foods from your regular diet.
  • Limit alcoholic beverages. Your body will metabolize the alcohol first. The food will sit and wait.

Are you watching your weight? Learn more about your idea. weight by taking a free online quiz.

Dr. Nick Pryomski is a family medicine physician at Aurora Health Center in Racine, WI. 

Read more:

Related Posts



  1. I have to disagree with your over all message for #”5. Multiple small meals during the day are better for metabolism than three square meals.” “Studies show multiple small meals do not boost metabolism, so this is a myth.”

    From other medical lectures I’ve attended they have explained. Eating several smaller meals helps keep your blood sugar stabilized, and decreases insulin spikes reducing the chance of a fatty liver and heart disease. Which in turn keeps weight off. It may not directly increase you metabolism but is essential with regard to keeping low body fat.

  2. My only concern is that the headline says “8 metabolism myths debunked,” but five of the eight theories presented are said to be true, so five are confirmed, three are debunked.

Subscribe to health enews newsletter

About the Author

Dr. Nicholas Pryomski
Dr. Nicholas Pryomski

Nick Pryomski, MD, is a family medicine physician at Aurora Health Center in Racine, WI.