Some of us complain that our metabolism is too fast, and we can’t gain weight while others of us complain that our metabolism is too slow, and we can’t lose weight. No matter what, it seems like we will always end up complaining. I can’t solve that, but I can tell you a bit about what metabolism is and what it has to do with weight loss or gain, as well as whether or not you can do anything about it.
Simply put, your metabolism is the sum of all the chemical reactions happening inside your body. Your body, just like a car engine, is a machine, and it is working 24/7 completing various chemical reactions to make the substances your body needs or to get rid of the substances your body does not need. And, like any good machine, your body needs fuel in order to run those chemical reactions. Food is that Fuel.
Therefore, when we refer to our metabolisms in terms of weight loss or gain, we are usually referring to the use of this fuel or the burning of calories and not so much about the specific chemical reactions taking place. Furthermore, the number of calories your body burns at a given time is referred to as your metabolic rate (Arnarson, 2018).
Take a moment and think of some of the times when you used energy and therefore burnt calories…
…you probably thought of the time you had to run 3 blocks because your neighbors’ Chihuahua was chasing you, or the time the elevator broke in your dorm, so you had to carry your Mini-Fridge up 4 flights of stairs, or maybe even the time your significant other convinced you to go to their Pilates class with them.
Well, did you also think about right now? While you are sitting here reading this, the muscles in your eyes are moving, your heart is beating, your lungs are breathing, your brain is thinking about what a great blog post this is. All of this takes energy whether you think about it or not and all of this plays a role in your metabolic rate.
A person’s Basal Metabolic Rate is the number of calories that are burnt or used up in order to complete all of those basic life functions while at rest.
Believe it or not, while you are actually eating food, you are not only consuming calories, but you are burning them as well. Your mouth, your stomach, and all your intestines are working after all. The number of calories you burn while consuming and digesting food is referred to as the thermic effect of food.
Maybe the most obvious way to burn calories is through exercise and that number of calories is referred to as the thermic effect of exercise.
Finally, as you are sitting here, reading this, you may be adjusting your posture, bouncing your leg or fidgeting with your hair. All of these tasks…REQUIRE ENERGY! The number of calories burnt while doing these things is referred to as one’s non-exercise activity thermogenesis. (Arnarson, 2018)
I have touched on Basal Metabolic Rate (BMR) in past blog posts and how it is a good number to know if you are trying to change your weight. Simply put, eating more calories than you burn will cause you to gain weight and eating less calories than you burn will cause you to lose weight. Therefore, having a faster metabolism (higher BMR) will help you burn more calories quickly and therefore make it easier to lose weight. And, vice versa, having a slower metabolism (lower BMR) will burn less calories and make it easier to keep on or gain weight. So now the obvious question is how can I manipulate my metabolism to meet my goals? Well, it's not that simple...
Metabolism is affected by many variables, and most of them you can’t control, and are also not well understood by science. These include genetics, age, and sex. However, interestingly enough, a recent study analyzed the total daily energy expenditure (number of calories burnt each day, including exercise) of 2,000 participants aged 8 days to 95 years old and found that energy expenditure remains stable in adulthood (20-60 years old), even during pregnancy. The energy expenditure did decline from children ages 1-20 and with older adults after the age of 60, meaning these participants had slower metabolisms (Pontzer et al., 2021). So, while age does play a role on your energy expenditure and therefore your ease at changing your weight, it is only during the beginning and end of our lives and most of us cannot blame our struggles on age.
Something that affects metabolism that you can change, however, is your body composition. Muscle takes a lot more energy to function than fat and therefore having a higher ratio of lean muscle in your body will cause you to have a higher resting metabolic rate (Frey, 2021 and Belluz, 2018). Also, believe it or not, actually eating food will help you have a faster metabolic rate. Diets that have you starve yourself for multiple days in a row are actually doing more harm than good. When you starve your body, your body notices and goes into “starvation mode.” In order to prevent your body from completely starving and dying, it begins to slow down your metabolism and burn less calories (Arnarson, 2018). Research has shown that this slowdown in metabolic rate sticks around even when you stop dieting (Belluz, 2018).
So, the moral of the story is, if you are trying to lose weight and therefore would benefit from a faster metabolism, one thing you could do is lift weights to put on some muscle and also eat in a calorie deficit but NOT starving yourself.
If you are trying to put on weight and would therefore benefit from a slower metabolism, one idea is simply eating in a calorie surplus as this will not only cause you to gain weight, but it will also help slow down your metabolism, and lead you to gain even more weight (Swick, 2017).
Well, there you have it, a basic overview of what metabolism is, how it impacts your weight, and how you can control it to an extent. I personally think we are all better off when we have a better idea of what is happening inside our bodies and how the foods, we eat effect us. This knowledge only makes us more powerful and more successful at reaching our goals!
Arnarson, Atli. “Fast Metabolism 101: What It Is and How to Get It.” Healthline, Healthline Media, 17 Dec. 2018, www.healthline.com/nutrition/get-a-fast-metabolism.
Belluz, Julia. “Most of Us Misunderstand Metabolism. Here Are 9 Facts to Clear That Up.” Vox, Vox, 4 Sept. 2018, www.vox.com/2016/5/18/11685254/ metabolism-definition-booster-weight-loss.
Frey, Malia. “Calculate Your Basal Metabolic Rate to Lose Weight.” Edited by Anisha Shah, Very well Fit, 28 Feb. 2021, www.verywellfit.com/what-is-bmr-or-basal-metabolic-rate-3495380.
Pontzer, Herman, et al. “Daily Energy Expenditure through the Human Life Course.” Science, vol. 373, no. 6556, 12 Aug. 2021, pp. 808–812., doi:10.1126/science.abe5017.
Swick, Raiselle UNC Chapel.“How to Slow down Your Metabolism to Maintain or Gain Weight.” Spoon University, 28 Apr. 2017, spoonuniversity.com/how-to/how-to-slow-down-your-metabolism-to-maintain-or-gain-weight.
A special thank you to all my friends and family who have not only supported me on my journey but have helped along the way. None of this would be possible without them. Remember to take time to appreciate those in your lives!
Copyright © 2020, 2021 Nick Siegel, all rights reserved