Skinny people have a fast metabolism, and fat people have a slow metabolism, isn’t that how it is? Well, if we take a look at our diet culture it seems like the metabolism is the secret sauce to maintaining a naturally lean body. But what does it mean to “have a fast metabolism?”. Is it really true that some people can eat whatever and how much they want, not exercising, and still stay lean?
What is metabolism?
You might have this illusion that our metabolism pretty much just burns fat and keeps people skinny. But, my friends, our metabolism deserves way more credit than that! Our metabolism doesn’t only work around the clock, but it’s actually the thing responsible for keeping us alive. I mean, yes, of course our heart is pretty important as well, but our metabolism keeps our bodies alive on the cellular level. The part where it burns calories is just a small part of its functions, and we call that our energy expenditure. So, besides being a word that gets thrown around like a football between American men during Superbowl, it’s actually a very complex chemical process that takes place in our bodies at all times.

Can you speed up your metabolism?
Eat spicy food, drink green tea and coffee, the list of things that claim to speed up your metabolism is endless! Are the extra cups of coffee, and sweaty dinners actually worth it? To keep it simple, yes you can “speed” up your metabolism, but it has nothing to do with the additional chilies your sprinkle on top of you dinner. To really understand the science for slower or faster metabolisms, we need to put our learning glasses on and dig a little deeper than the surface.
How does the metabolism work?
First or all we need to get down and detailed about our metabolism, and more specifically our energy expenditure. We can split up this process into three parts:
Resting metabolic rate (RMR)
This is the energy you burn simply by being alive. You could lay still in bed all day and your body would still burn these set amount of calories. Genetics do play a small role here, we can’t deny that, but besides this the simple fact that we are breathing adn our heart is beating, burns calories. Believe it or not, but our resting metabolic rate stands for 50-80% of our total energy expenditure. Muscles love to burn energy, so if you have more lean muscle mass, your RMR goes up. Men also tends to burn more energy during RMR. Yup, it’s actuallyy true that men needs more energy than woman (depending on the activity level of course!!!!).

Energy burned during physical activity
This should be pretty self explanatory. During exercise we use energy and burn calories, pretty straight forward. Our gym sessions stands for about 20% or our total energy expenditure. This is based on moderate exercise, so if you’re a pro athlete or workout a lot, this percentage would obviously be higher (and your RMR, since you probably have more lean muscle mass).
Thermic effect of feeding
Every time you eat and drink your body has to burn energy to digest and absorb the food. What you eat has the power to determine how effectively the food is broken down and how much energy you’ll burn in the process. By focusing on more fibers and protein out body needs more energy to digest the food. This is why the food you eat is so important. And even though 100 calories of candy vs 100 calories of carrots has the same energy amount, they are processed very differently in our body. By eating the right type of foods you could technically burn more calories by simply eating. Take celery for example. For the body to break down celery, it requires more energy than the celery contains, meaning, you’re actually burning more than you consumed. Pretty wild, right!?

NEAT or non exercise activity thermogenesis
This little guy is a key component in our metabolisms energy expenditure which has a larger impact on our daily energy expenditure than we might think. What is this neat thing you might wonder? Besides being a pretty neat word, it’s basically all the other “non purpose exercise” activities that you do during a day. This includes everything from walking, to fidgeting, to moving your hands when you talk or text. All these other movements that we do all goes into our overall energy expenditure. So when people say that they workout all the time but still don’t feel like they’re seeing results, it might be because the other time of the day is spent on their ass, Netflixing, with minimal movement.
Of course exercise st really healthy for us, and the increased muscle mass increases our BMR, but the NEAT activity we do during a day can result in way more energy burned than a 30 minute gym session. The amazing part about NEAT is that it’s easily added into our daily routine without much extra effort.
Increase our NEAT
Let’s talk about how NEAT will equal out during let’s say, a week. Let’s say you run an hour a day on the treadmill and burn around 400 calories during that hour. If you also during the day, stand up at your desk, take breaks and walk around the office a little, vacuum clean, walk to get your groceries, or take the stairs instead of the elevator, you could all of a sudden be burning an extra 500-1000 calories a day. And it’s easy!
If you think about it, most “naturally skinny” people hive around a lot. They might be running around the house doing small chores, have high energy, fidget a lot, or walk around more. Of course, we can’t oversee the fact that genetics do play a small roll in our energy expenditure, but we aren’t doomed to be slaves under a “slow metabolism”.

Don’t obsess
To finish up this post I have to stress the importance of not getting to obsessed over these daily NEAT movements. While it’s healthy and natural to move around more during the day, too much of a good thing will end in an unhealthy obsession. With this in mind, I hope to see you in the stairways!
Sources
https://www.ncbi.nlm.nih.gov/m/pubmed/2691813/
https://www.news-medical.net/life-sciences/What-is-Metabolism.aspx
https://www.precisionnutrition.com/digesting-whole-vs-processed-foods