Metabolism 101
As a teenager and young adult who was a little too concerned with my weight, I remember being envious of people who seemed to be able to eat anything they wanted and remain thin. We referred to those lucky people as having a high metabolism.

But what exactly is metabolism? Can it be too high or too low? And if so, is there anything you can do about it if yours is out of whack?
First a reminder, while I am a certified health and wellness coach, I am not a healthcare professional. If you need medical advice, please see your healthcare provider.
What is metabolism?
In a nutshell, metabolism is the total set of chemical reactions in your body that change food into energy and build body tissues.
The nutrients present in the foods that we eat and drink provide us with carbohydrates, fats, and proteins that act as helpers for every single reaction that takes place within the body.
Metabolism is made up of two parts: catabolism and anabolism. Catabolism refers to the breakdown of molecules to obtain energy, and anabolism refers to the building up or synthesis of larger molecules from smaller ones. Anabolism is responsible for growing, healing, and making new cell structures in living things.
Catabolism and anabolism require a precise balance. Imbalances of the two result in breakdown and usage of stores or a buildup of stores. Both can have negative effects on body tissues.
Factors influencing metabolism
As we move through life, our bodies have different energy requirements and metabolic rates based on a number of factors:
- Lean body mass/muscle mass — muscle has much greater metabolic activity than fat tissue.
- Age — as we age, fat mass tends to increase.
- Body size or composition — people with larger bodies generally have higher metabolic rates because their organs are generally larger and they have more fluid volume to maintain.
- Physical activity — exercise increases the rate of energy breakdown.
- Hormones — for example, hyper or hypothyroidism can contribute to a metabolism overdrive or one that is sluggish.
- Drugs — nicotine and other drugs can increase the metabolic rate, while other drugs such as antidepressants and steroids can increase weight gain.
What is hypermetabolism?
Hypermetabolism means you have a very high metabolic rate and your body burns more calories than it should.
Symptoms of hypermetabolism
According to Cleveland Clinic, the most common symptoms of hypermetabolism are as follows:
- Unexplained weight loss
- Increased appetite
- Sweating excessively
- Fatigue
- Quick and/or irregular heart rate
- Anemia
Managing hypermetabolism
For many of us living in a weight-obsessed society, a fast metabolism might sound like a good thing. However, hypermetabolism can lead to muscle weakness, bone density loss, heart problems, kidney damage, and a weak immune system.
So what can you do to manage or treat hypermetabolism? First of all, seek the advice of a healthcare provider. They may suggest a custom diet, medication, fluids, or restricted physical activity.
If you don’t yet have hypermetabolism, you can reduce your risk of developing it by doing the following:
- Maintaining a healthy weight
- Eating a healthy, well-balanced diet
- Getting regular exercise
- Having regular medical checkups
What is hypometabolism?
Hypometabolism means you have a very low metabolic rate, and your body burns fewer calories than it should.
Symptoms of hypometabolism
According to health experts, there is a long list of hypometabolism symptoms. Some of the most common are as follows:
- Chronic fatigue
- Abnormal coldness
- Abnormal weight gain
- Dry hair, skin, or nails
- Slow digestion
- Brain fog
- Nervousness and irritability
Managing hypometabolism
True hypometabolism is often a result of other contributing diagnoses, so it is important that you see a medical professional to determine the underlying cause of your hypometabolism.
If you simply wish to optimize your metabolism, the following things may help:
- Eating a healthy, well-balanced diet
- Regularly performing strength training exercises to increase muscle mass
- Participating in regular physical activity
- Having regular medical checkups
In summary
As with so many aspects of health and wellness, optimizing metabolism in an otherwise healthy person boils down to living a healthy lifestyle, paying particular attention to nutrition and physical activity.
Your turn
- Have you ever done anything to try to change your metabolism, or did you grow up believing one is either blessed with a “good” metabolism or not?
- Do you know your lean body mass percentage? Yes or no is okay; you don’t have to share the number with us!
- What else is on your mind? Anything at all; I just love hearing from you.
Image by Silviu on the street from Pixabay

Hi Christie, I’m sure our metabolism slows more with each decade. I definitely ate more and exercised less in my 20’s and never had issues with watching my weight. Menopause adds another layer to it all. That being said, being aware and eating healthily, exercising regularly, and just being grateful to be alive and well, seems to work for me. 🙂
Yes, Leanne, I think you are right that there are many things that play into making it more difficult to maintain a healthy weight as we age. I have found that I am in a better position at this point in my life to focus on healthy eating and regular physical activity. For me, that has helped offset the typical weight gain in midlife. I too am grateful to be alive and well.
I was just like you, Christie! I wanted to be that tall (anything over 5’3″ is tall to me) girl with the good metabolism! Now, I’m just happy to be healthy. I do have hypothyroidism and had an endocrinologist tell me I had Hashimoto’s. When he ordered about 10 pages of blood tests, I went to my PCP and asked him if he could manage my thyroid. He looked at the tests and said they’d cost $1000s. He also assured me he could manage my thyroid so I’ve never looked back. I would love to be the person who can eat anything and everything and never gain an ounce, but I’m not going to be. So, I just eat as healthily as I can and live my life! Thanks for all the information!
https://marshainthemiddle.com/
I too have hypothyroidism, Marsha. I started treatment with a specialist. Now that my levels are in a good place, that specialist happily handed the care off to my primary care physician. I don’t want to brag, but I am tall at 5’7″. Of course, in junior high and high school, I hated being one of the tallest students, especially being taller than many of the boys. Now I am content with my height.
I always thought of your Metabolism as something you were blessed or burdened with and that you had no control over it. I thought if you had a high metabolism, you were lucky because you would burn more calories and naturally be thinner. After reading this blog I realize it can have negative effects as well. I have symptoms for both hypo and hypermetabolism, but I also do the things you listed for maximum metabolism health, so hopefully that helps balance it all out.
We grew up with the same idea about metabolism, Cindy. And, yes, it sounds like you are doing all the right things for metabolic health. The rest is to nature…or genes…or something.