Metabolism is all the rage in nutrition and fitness these days.
How to boost it
How to prevent aging from slowing it down
Maybe you’ve heard of any, some, or all of these phrases.
There’s a lot of information out there on “metabolism”, some good and some not so good.
There are supplements that claim they can help give you the metabolism of a 20 year-old. There are some that increase your “fat metabolism” so you can lose weight.
This plug word has become such a key factor in popular marketing.
But do any of them work? CAN you increase your metabolism? Does it slow down with age? Heck...what even is “metabolism”? How do you burn calories?
All of this we hope to teach to you today in this blog. Not only will we tell you a bit more about your metabolism, but also hopefully give you some clar-e-ty on how you can enhance your metabolism and improve your metabolic health.
A spoiler alert...you’re not broken...and neither is your metabolism.
So without further ado, let’s get into it!
What is “metabolism”?
To be honest, “metabolism” is very context dependent. It’s way more than just burning calories or utilizing fuel from some carbs. Below are the three main contexts in which your body utilizes “metabolism”.
Clinical: physical and chemical processes that convert and use energy
Biochemical: chemical reactions involved in maintaining the living state of cells
Nutritional: burning of calories
Yes, while they all seem closely related...i.e. utilization of energy to maintain homeostasis, it’s important to remember primarily that your metabolism involves way more than eating protein, carbs, and fats to get you through a workout or help you lose weight.
In the biochemical world, carbs, fats and protein are metabolized in different ways. They are metabolized to use and store fuel (via carb metabolism to glucose and glycogen in muscles and your liver and fat metabolism to fatty acids and triacylglycerides in fat cells). They are also metabolized to form essential compounds needed for cell survival or muscle protein synthesis (via protein metabolism to amino acids).
Glycolysis, the Citric Acid Cycle, Electron Transport Chain, Cori Cycle, Pentose Phosphate Pathway, etc. are your body’s biochemical metabolic machinery that break down food to store or use as energy...or to produce ATP.
Because energy is needed for survival.
Cells in your body need to survive. They do this through fuel, nutrients, and energy (metabolism), waste removal, and maintaining an appropriate environment (i.e. low stress).
In the context of biochemical metabolism, it’s important to remember what your food gets “turned into” or metabolized into.
Carbs to glucose
Fats to fatty acids
Protein to amino acids
SO...in the context of “metabolism” in the biochemical sense, it’s the process of breaking down macromolecules found in food into not only their functional part but also they’re building block form. For example, a complex carbohydrate is a combination of glucose molecules) and a protein is a code of amino acids grouped & folded together in a specific manner.
Why is this portion of metabolism important to discuss? MAINLY because tow of our macros that we consume—fats and protein—are what we call essential, our bodies can’t make any of them on its own. While your body can synthesize glucose on it’s own, it’s still pretty important to consume.
ALSO, it’s another reminder that metabolism is more than losing weight. When we hear from fitspo coaches “your metabolism is broken,” you need to think critically here. IF your metabolism IS indeed broken...you’re dead because you can’t break down any food group into it’s functional pieces needed for fuel and survival. You may have some processes within your metabolism altered and slowed down, but that’s not “damage” nor is it “broken”.
This is a subject that is VERY complex and very much beyond the scope of nutrition coaching. This is information that Biochemistry PhDs are expected to know and understand, so if this went over your head, that’s okay!! We don’t expect you to know this. We only hope you see that this is a complex system that’s WAY more resilient...and finetuned...than we usually give it credit for.
These nuances will become important as you keep reading!
What burns calories?
Now let’s get into the world of nutritional metabolism...because let’s be honest, that’s why you’re here.
There are four main categories that make up how you burn calories.
Resting/Basal Metabolic Rate (RMR/BMR)
Thermic Effect of Food (TEF)
Non-exercise Activity Thermogenesis (NEAT)
Exercise Activity Thermogenesis (EAT)
If you’ve followed us for a while, we talk about this a lot so you might know the answer here.
If you had to guess, what accounts for the largest portion of calorie expenditure out of the four groups above? What about the smallest? Specifically, where does exercise (EAT) fall?
If you said that EAT is the smallest category that makes up calories expended, then you would be correct.
As you can see above, your BMR, also we'll refer to as RMR, (they’re slightly different but used interchangeably here) makes up the LARGEST portion of calories burned in a day.
Exercise is the smallest at just a whopping 5%! Does this surprise you? It should!
It requires a TON of energy to keep you alive. Your RMR/BMR is the bare number of calories to exist if you never got up off your couch. For MOST people, this is 10x your bodyweight.
Your RMR keeps you alive. It’s responsible for the energy required for organ/tissue function. Below is the energy breakdown for essential organs and tissues that are included in your RMR:
6cal/lb skeletal muscle
200cal/lb heart tissue
That's a LOT of calories!!
A couple of factors determine your BMR/RMR:
Weight/Lean Body Mass
Genetics (doesn’t determine but sure does affect significantly)
Now as you start to think of the theme of the blog article today, it's all about boosting your metabolism.
Start to think from the categories listed above...what do you really have control over?? (hint there's two factors, but really only one).
TEF – Thermic Effect of Food
It requires energy to break down food, some food groups more than others.
Protein requires about 20% of calories consumed to break down.
Starchy/fibrous carbs require about 10-15%.
Fats & simple carbs require 0-5%.
SO...when we think about getting the most bang for our buck, we’re looking at a whole foods, protein-rich diet.
Take a 2,000-calorie typical Western Diet. It’s low in protein and high in hyperpalatable, processed foods. Your TEF in this diet is roughly 10%. That means you’re likely expending roughly 200 calories breaking down and digesting food that day.
Take, now, a 2,000-calorie NON-Western Diet. It’s one that’s high in protein and whole foods, so lots of nutrients and fiber as well. You’re looking at a TEF of 20-25%. You’re roughly expending 400-500 calories breaking down and digesting food that day.
While we DO encourage flexibility and not shaming any food groups, there is a difference in the foods you’re feeding yourself.
When we think of areas to boost your metabolism, do you think the thermic effect of food will play any role?? (hint, probably!)
You burn calories by doing things OTHER than hitting the gym. In fact, you do a LOT more in your 23 hours of the day outside of the 1 hour you spend in the gym.
NEAT ranges from walks to laughing and even all the way to fidgeting. Crazy, right??
A person with a physically demanding job will likely have a higher metabolism than someone who is sedentary all day and maybe hits the gym for an hour long CrossFit class a couple times per week.
Over an 8 hour period, these activities--related to your work--burn the following calories:
Sitting in a chair - 280 calories
Seated but frequent standing and moving - 650 calories
Standing (like a standing desk or a job that requires you to be on your feet) - 860 calories
Strenuous work - 2250 calories
What you do for work and how you break up your day MATTERS...and maybe even more than that one hour you spend at the gym.
If you walk 1 mile in an hour, you double your energy over pure rest.
This is why Clar-e-ty coaches encourage daily movement first over getting to the gym and crushing a workout. YES it matters, but the other hours outside of that matter more.
Finally, to our last and smallest category and likely the one you put all your energy into.
Not that that's WRONG per say. There are a NUMBER of benefits to exercising beyond your metabolism. Injury prevention, immune health, inflammation, aging, insulin sensitivity, etc. are all other reasons to exercise.
But when it comes to your metabolism, this is a 5% category. MAYBE you exercise 2hrs in a day, but likely not 7 days a week. There are OTHER factors to consider that have more bang for their buck, if you will.