Recently I haven’t been able to stop worrying about the dreaded “starvation mode”, and that I wasn’t doing enough to speed my metabolism up… So I looked into it, and I learned a lot of very interesting things! Mainly that a lot of the things I thought I knew about my metabolism was completely backwards, so let’s talk about it! :)
NOTE: I AM NOT AN EXPERT! I just did some basic research and want to share what I found.
As always, all sources used are at the bottom of the post.
So,, what even IS my metabolism?
The word metabolism refers to the chemical processes that go on continuously inside the body in order to to keep you alive and maintain homeostasis. This takes energy to do, which is measured in kilojoules (kJ)
These chemical processes can broadly be divided into 2 groups: catabolism (breaking down food), and anabolism (building repairing our body).
So again: “metabolism” is not a SPECIFIC chemical process, but rather the term we use when talking about ALL of the chemical processes your body uses to keep you alive.
Wait but now I’m confused… I thought my metabolism is what controlled how fast I burn what I eat??
It is! It’s just a bit more complicated. Your body turns food into energy, and uses that energy to function. Any extra energy the body takes in is stored (mostly as fat). Your body’s metabolic rate (or total energy expenditure) is divided into 3 parts:
Basal Metabolic Rate (BMR)
This is the energy you use to keep all the body’s systems functioning correctly (including breathing, keeping your heart beating, adjusting hormone levels, and growing/repairing cells)
Your BMR accounts for 50-80% of your body’s daily energy usage, and seems to be what people are usually referring to when they talk about “speeding up” or “slowing down your metabolism”
Thermogenesis (Thermic effect of food)
This is the energy your body uses to digest food and drink, and to absorb, transport, and store nutrients.
Thermogenesis accounts for 5-10% of your body’s daily energy expenditure.
Energy used during physical activity
This refers to energy used by physical activity. this includes planned exercise like biking, running, walking, swimming, etc; and all incidental activity like moving from room to room and even fidgeting!
This one really varies from person to person, but for a person who has about 30 minutes of moderate-intensity physical activity a day, physical activity accounts for about 20% of daily energy use.
So basically, a lot of people use the term “metabolism” when they are talking about how many calories their body burns just living when they should really be using the term “BMR”.
And when people say things like “the daily recommended calories for an average adult is 2,000” they are saying that the average person’s metabolic rate uses about 2,000 calories worth of energy a day! that’s kinda crazy, right?
Ok cool, so can the “speed” of my Metabolic Rate change?
Yes! Kinda.
You see, Thermogenesis is out of your control, and your BMR can kinda be affected by different things you can do, but as far as I know the changes are not significant. And you can increase your physical activity to burn up more calories to, but I get the feeling you guys know that ;)
Your BMR is the only one of these that is both in your control, and not. It’s calculated using your sex, age, hight, and weight; but is affected by things like starving (decrease in up to 15%), caffeine (small increase), and even the temp of your environment.
Unfortunately, there is no magic thing we can do to just make our bodies use significantly more calories for our BMR. We CAN try to maximise our BMR by doing strength training (muscle requires way more energy to maintain than fat), and by “high restricting” or planning some high calorie days to help prevent your BMR from slowing due to lack of food!
A quick note for my fellow nonbinary and trans peeps: There is plenty of research out there that shows that your “biological sex” matters less than your “hormonal sex” when calculating your BMR. this is because most BMR calculations look for lean body mass vs fat cause they require different amounts of energy to maintain, and women are more likely to have more body fat (there are many reasons for this, but I won’t be going into it today).
So you can do a couple of things:
1) If you have not taking hormones, then you can calculate using your AGAB (assigned gender at birth)
2) If you ARE taking hormones, or are “fully transitioned” then you could calculate using “male” if your taking T, and “female” if you are taking E. If your microdosing or your transition is incomplete then you could calculate twice (once with male, and once with female) and average the 2 numbers
3) You could look for calculators that DONT include the gender question! they exist! The Katch-McArdle Formula for calculating your BMR does not have the gender question.
That was a lot, can you summarize it?
Absolutely!
TLDR: “metabolism” is an umbrella term for “everything your body does that requires energy.
Your metabolic rate (aka how much energy your body uses) is determined by 3 parts: thermogenesis, BMR, and physical activity.
Thermogenesis is out of your control
BMR is affected by your actions to an extent, but you can’t "speed it up” to use more calories. It can be slowed down if your body feels it needs to conserve energy because you aren’t eating enough, an it can slow down by 15%
Physical activity is totally in your control (for abled body people anyway, I know physical activity is different for everyone). The more you move, the more energy your body uses, and the more calories your burn
As always, I love you all, drink some water, and stay safe <3
-dismal
Sources (I encourage you all to read as they go more in-depth and are easy reads)
this is gonna be a long one but if the title applies to you, i IMPLORE you to read the whole thing. if it doesn’t, please reblog. you might save someone from this fucking nightmare.
i found a diary entry on the day that i decided to go on tumblr and search up “thinspo”. i was feeling awful about my body for some time but never really thought about calories or eating less or anything.
i wrote (verbatim): “i don’t want to have an eating disorder or anything, i just want to lose 10lbs”
not even a month later, it was like nothing could stop me from reaching my goal. i kept telling myself i wasn’t in too deep. i ate 500 cals a day and no more. i exercised 300 cals away.
now, the only thing i want is that blissful ignorance. not even thinking twice about my body. not caring what i ate. understanding the boundaries of healthy eating. not feeling faint and dizzy when standing up.
I WISH THAT I HAD SEEN A POST TELLING ME THAT IF YOURE LOOKING AT THINSPO “just to motivate you,” THIS IS THE BEGINNING OF A PROBLEM AND THE START OF A CYCLE YOU WILL REGRET EVER BEGINNING AS SOON AS YOU REALIZE YOU HAVE NO CONTROL OVER YOUR ADDICTION TO STARVING. at this time in my life i would listen to NOBODY and NO POST could stop me from slowly crawling into the arms of my developing eating disorder. BUT IM BEGGING YOU, IF YOU ARE BEGINNING THIS STRUGGLE, GET OUT WHILE YOU STILL HAVE CONTROL. you see all these posts telling you that over 1,000 calories is disgusting and so on, DO NOT LISTEN. PLEASE! you have no idea how quickly this shit can get in your head. no matter what your intentions for going on the ana tags are, LEAVE THEM NOW IF YOU STILL CAN. LEAVE AND DONT LOOK BACK. OR ELSE YOU WILL END UP DISORDER RIDDEN AND HATING YOURSELF LIKE ME, because once you’ve been here long enough, it doesn’t matter if you hit your UGW or you’re still at your sw; you will always always always see yourself as fat. that is a promise. and it’s disgusting.
this is a dirty, horrible disease that teaches you to hate yourself. it perpetuates symptoms of anxiety and depression and causes thoughts and feelings that you never believed possible in yourself. it destroys your identity, your relationships, you family life, your grades, your ambitions, and your health. if you have a choice not to fall into it, DONT FUCKING DO IT. don’t fucking do it for the love of god.
there’s not a person in this world who hasn’t embarrassed themselves or hurt someone or made a mistake. learn and grow from these things, rectify them if you can, but don’t dwell on them. we are all human; we are all imperfect.
