The Biggest Myth About Your Metabolism Debunked

by Moin Uddin Ahmed Tipu

You’ve probably heard that your metabolism slows down as your age. Turns out, that isn’t entirely true. A new study revealed that your metabolism actually remains steady throughout most of your adult life.
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Every minute of every day, your body is converting food or stored fat into energy to keep itself going—pumping blood, expanding and contracting your lungs, plus all kinds of stuff on a cellular level, like making new cells and getting rid of old ones. That’s your basal metabolic rate. On top of that, there’s the energy you expend to move around and do the physical activity of your day… plus the energy it takes to process your food into energy in the first place. The exact amount of energy it takes to do all this varies from person to person. If someone burns through a lot of energy in a given amount of time, we say they have a fast metabolism. Those who burn less energy in the same amount of time have a ‘slow’ metabolism.

There are so many crash diets and ‘quick fixes’ that promise to speed up your metabolism to help you achieve weight loss, but the truth is that the speed of your metabolism is determined almost entirely by your genes. And research is telling us that metabolism actually plays a relatively small role in weight management anyway—the biggest factors for this are good ol’ diet and activity levels.

So how about that “our metabolism gets slower as we age?” factoid? Well, for years it was widely accepted by the scientific community, but a 2021 study has given us a much-needed update. A team of 80 co-authors analyzed metabolic rate data collected by different labs over the course of 40 years. This data comes from more than 6,400 people ranging from 8 days old to 95 years old. Turns out, there are metabolic shifts in our lives, but probably not when you think. Our calorie-burning peak is actually when we’re infants, when from birth to 15 months we’re using crazy amounts of energy to grow our brains and our bodies. Infants actually burn calories 50% faster than adults! After these early days, our metabolism slows down throughout childhood and adolescence before it settles around age 20 into our adult rate. Then at 60 years old, our metabolic rate drops again, and keeps declining until the end of our lives. But between 20 and 60, that biiiiig span of time in the middle? Our metabolism stays pretty much the same, even through big changes like pregnancy or menopause.

#seeker #science #metabolism #health #fatburning

Read More:
Daily energy expenditure through the human life course

Pontzer et al. report that energy expenditure (adjusted for weight) in neonates was like that of adults but increased substantially in the first year of life (see the Perspective by Rhoads and Anderson). It then gradually declined until young individuals reached adult characteristics, which were maintained from age 20 to 60 years.

What We Think We Know About Metabolism May Be Wrong

There are more than 80 co-authors on the study. By combining efforts from a half dozen labs collected over 40 years, they had sufficient information to ask general questions about changes in metabolism over a lifetime.

What I learned about weight loss from spending a day inside a metabolic chamber

There are only about 30 metabolic chambers in the world, and the NIH is home to three. These highly sensitive, multimillion-dollar scientific instruments are considered the gold standard for measuring metabolism.

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Rey Luna January 12, 2022 - 11:38 PM

As a reclusive gamer, I've been the in the same shape for a few years, I gain some weight and I loose some but I've stayed close to 250 to 270lbs most of my late teens early adulthood

Rob Enhoud January 12, 2022 - 11:42 PM

0:05 I like running on an empty stomach simply because thinking about what I'm going to eat when I'm done gives me motivation to run harder.

zukodude487987 January 12, 2022 - 11:44 PM

What i hate is when skinny people tell the fat person that they have a fast metabolism. Like no, just no. The fat person has a higher metabolism, because they have more mass to carry and maintain. Skinny people usually just eat very little and justify their low appetite on the lowest forms of evidence aka anecdotes. Take them in a controlled scientific conditions and their reasoning starts to decline.

People dont have a fast metabolism based on if you are skinny or not, but rather on your body mass and activity level. You can have a high metabolism if you are fat and active, but you just eat so many calories that you increase in weight. You can also be skinny and have a low metabolism, because your body mass is low and you eat miniscule amount of food. Peoples size isnt determined by their metabolism, but rather if they are in a caloric surplus. I at one point burnt 4500kcal each day, but i was bulking so i ate 5000kcal to gain weight, just because my metabolism was high does not mean i cant gain weight.

trckojr January 12, 2022 - 11:45 PM

0:28 Belgrade marathon

Alparslan Korkmaz January 12, 2022 - 11:47 PM

Nice video.

Pierice 1o1 January 13, 2022 - 12:07 AM


Chris January 13, 2022 - 12:28 AM

I still think dieting slows metabolism. When you decrease the amount of energy that you put into your body it counteracts this by slowing the metabolism to extract more energy. Which is why you want to modify your food intake to be more steady throughout the day rather than eating big meals in one sitting. Athletes live by this rule.

IT Tips and Tricks January 13, 2022 - 1:05 AM

Hey You loss some weight >>>>???

BFBF Rob January 13, 2022 - 1:17 AM

Not a single mention of the largest determining factor muscle mass. Muscle requires more calories. If you don’t use the muscles or don’t feed them enough calories they will deteriorate. As we get older we generally get more sedentary and our muscles deteriorate requiring less calories to maintain which some people would say is slowing our metabolism.

Hamstercat14 January 13, 2022 - 1:27 AM

3:41 to what.. to what! to whaaaaaat!!

David Furor Curser January 13, 2022 - 1:27 AM

does she become more beautiful everyday? how does she do it?

Donny Tee January 13, 2022 - 1:36 AM

Question: Why do tears cause red eyes?

pyronac1 January 13, 2022 - 1:49 AM

dont eat after 7pm???? i feel bad for nightshift workers.

Mark Shiman January 13, 2022 - 2:03 AM

Your genes are everything. Except personality??

zsmb25 January 13, 2022 - 2:11 AM

How does the microbiome affect metabolism?

Stitches January 13, 2022 - 2:13 AM

Talking about weight, missy, did you lose a load of lockdown weight?

Mark Whittum January 13, 2022 - 2:14 AM

What about the thyroid?

MrMysteryman00 January 13, 2022 - 2:50 AM

What is the minimum energy needed to metabolize food? Like at what point would you be unable to process food?

VAGABOND111 January 13, 2022 - 3:53 AM

Maren's looking the best I'v ever seen <3 great episode too!

Mirror Space January 13, 2022 - 4:05 AM

Unthink the topic. Eat and move and rest according to the needs of your body. [ in at 17757 views = 27 FNORD ]

Gustavo Marques January 13, 2022 - 4:31 AM

People think in terms of physics and chemistry to explain the world around them. But, when it comes to nutrition (even people with a scientific or a higher education background), they think about nutrition in terms of alchemy and magic and loose their reasoning. As a final year nutrition and dietetics student and soon to be dietitian I've never heard, EVER, the expressions "slow metabolism" or "fast metabolism" in the ENTIRETY of my college degree. Why? Because there's no such thing as fast or slow metabolism. The speed of a biochemical reaction also doesn't dictate if you store more or less fat, that's just a popular expression. Your body follows the laws of thermodynamics, organic matter that isn't used to produce energy is just transformed into something else. Most people don't even know that the lungs are the organs that excrete the majority of the fat they use to produce energy (organic matter oxidized by the body turns into H2O and CO2 and gets breathed out). There's only people who need more energy to maintain their bodies and/or spend more energy in their daily activities or people who need less energy to sustain their bodies and/or spend less energy in their daily lives. Someone with a lot of muscle doesn't have a "fast metabolism" they just need more energy to sustain their bodies because muscle is a very metabolically active tissue. In the opposite side, older folks do not have a "slow metabolism" they just have lower muscle mass and are more sedentary, lowering the amount of energy they consume. Hormones, genetics, medicine and environment are superfluous when it comes to increasing or or decreasing the amount of energy burned by an individual, although some clinical changes can make you spend more energy, "not speed up your metabolism" (for example, having a fever makes you produce more heat, therefore you burn more calories, the same happens when you have an infection because your immune cells need more energy to move because they're more active). The person you think as a "slow metabolism" probably doesn't move much, is small, as low muscle mass, is hungry all the time or makes food choices that can be healthy but are calorie dense (like adding olive oil to every meal, even though it seems that their just eating salads, those salads can be very high calorie). The opposite goes for people you think have a "high metabolism".

Bryan McCaffrey January 13, 2022 - 4:40 AM

Exercising can increase your BMR. Increasing the amount of muscle mass you have will increase your BMR

MLG klipz January 13, 2022 - 5:18 AM

Burn y’all always talk about slow metabolism but never fast metabolism 😭 I just want to get fat I literally eat a whole pizza and some whole get skinnier 😭

CPU January 13, 2022 - 5:18 AM

Causal explanation is a sophism against phenomenology. I hate the idea idea that myths are unreal. They are everything but unreal.
They shape the way we are, our reason to exists, our relationship to the world, how scientists became scientists. DO NOT CONFUSE MYTH WITH LIE.

Shiva Venuturumilli January 13, 2022 - 6:00 AM

Maren is back 🙂

Marantz 5006 January 13, 2022 - 9:34 AM

Mam, the background music is annoying as fuk

uabir January 13, 2022 - 9:37 AM

I just noticed that you've lost a lot of weight girl!

no body January 13, 2022 - 10:07 AM

I just started watching your videos but I want to thank you for putting in the effort to include humans of all backgrounds in your visuals.

3800Tech January 13, 2022 - 10:37 AM

I was always overweight as a kind and teen and even obese by the time I was 18. Then I got very ill due to endocrine/pituitary dysfunction and lost about 50% of my weight, dangerously underweight. 48Kg was my worst point. I got treatment and then eventually recovered and no longer needed treatment and I regained my weight but mostly muscle and minimal/healthy amount of fat and stayed like that til now in my mid 30s. I also eat way more and often compared to when I was obese in my late teens. Funny how something like that could turn things around the opposite to the norm.

Thomas Coolidge January 13, 2022 - 12:00 PM

Yay so happy to see ya again Maren!

Geoffry Gifari January 13, 2022 - 12:11 PM

hmm… but what is actually happening when one's metabolism is fast or slow? what determines just how fast cells eat up energy? does low metabolism equal low rate of processes (breathing? heart rate? digestion? slow rate of neurons firing?)

Kiran January 13, 2022 - 2:50 PM

Were you always this pretty ? 🤔

Nootka January 13, 2022 - 3:49 PM

What's the song name in the background?

Hans K January 13, 2022 - 4:32 PM

Start weight lifting/running and you’ll love food again

frosted1030 January 13, 2022 - 5:28 PM

The biggest influencer in weight change is hormones. Diet all you like, work out all you like, this will not affect your weight enough to be of value.

Veee January 13, 2022 - 5:50 PM

Tbh I think one other factor young adults gain wait and blame it on metabolism is that we don't have mandatory PE classes anymore so amount of exercise decreases drastically. (Of course, apart from those who do actively work out.)

keith wilson January 13, 2022 - 7:49 PM

So I grew up with 6 Brothers in a small country town with no fast food outlets. We were poor and ate all the same meals. I played three more sports than any of my brothers. Tennis, Soccer, Rugby League, Cross Country running, Swimming. Through Hot Summers 40 deg C and cold winters. Some of my Brothers did no sport just studied but ALL of them were Skinny. I had a thick layer of baby Fat that continued on until Adulthood. When I was 22 I was playing high level Rugby, Rugby League, Aussie Rules and training all week I was 95 kg my best Adult weight. When i stopped training and just played casual sport the weight went back up and I have never lost weight since even under strict dietary control. 5 years ago I was diagnosed with low Metabolism.

Mariano Alippi January 14, 2022 - 12:04 AM

Maren your metabolism makes you have such a beautiful voice, and that you are curious when creating innovative videos, but you also have to look for time to be with nature and do a lot of trekking in national parks, maybe there you can make your videos The videos by Seeker could be even more interesting if they are filmed in the middle of nature, and if you can't, you have to go to the Gym to balance the anxieties of such a demanding job.

Antryg Revok January 14, 2022 - 2:23 AM

woman in the video, your metabolism looks like a kapha-metabolism.

Please read both Frawley's "Ayurvedic Healing" and Kozak & Frawley's "Yoga for Your TYPE", to understand it.

I have personally experienced all 3 of the fundamental metabolisms, and now am in a blended metabolism.

Kapha can be undone.

Metabolism-change also has personality-change happen with it, which I have experienced.

( it is caused by the unconscious-LifeMind:
unconscious-LifeMind feeling threatened by famine/dieting/etc induces the slower kapha metabolism, to hold-onto stored body reserves, fighting-off death's threat. No energies-sensitivity ( compared with vata ) or muscle/force/fire ( compared with pitta ).

Vata is caused by unconscious-LifeMind's assuming that sacrificing all ( fat, muscle ) for energies/nerves driving.

Pitta is caused by unconscious-LifeMind assuming that torching fat & sensitivity/nerves for muscle/heat/force is the answer.

Pitta-Vata is my favourite metabolism, but we have limited ability to choose which metabolism our next years are going to be in.

It took many years to break my ultra-vata metabolism, the 1st time.

Western medicine that pretends these are not real is harming people's lives, but its prejudice cannot permit evidence to contradict its established-assertions, of course.

Pinto beans & Great Northern beans are healthy for kapha, avocado is healthy for vata.

Each of those are harmful to the opposite ones.


Easily testable, IF one happens to be asking the correct questions, but if one insists on not asking those, one can "prove" that there is nothing in them, of course…

Depends on one's integrity-addiction, vs establishment-addiction, doesn't it?

I have found no ayurveda-ingredients-list as accurate as Frawley's.

Your health would improve if you were sticking to the foods that are healing for your metabolism.

Do the experiment, & see, for yourself…

.. if you are willing to hold to evidence-based knowing, that is…

in kapha roasted corn ( like fresh corn harina tortilla ) are amazing.

Dan SW January 14, 2022 - 2:24 AM

Jeans are closely related to weight loss

Tragoudistros.MPH January 14, 2022 - 3:12 PM

Basal Metabolic Rate vs Metabolism Speed (fast/slow)…

It almost feels like the term "metabolism" is used too interchangeably…

misty cloud January 14, 2022 - 8:47 PM

China will fix this through gene editing

Vasilis Moutzouridis January 14, 2022 - 10:38 PM


Conan Clarke January 15, 2022 - 4:39 AM

Trying to loose weight its such a 1st world problem.

Kyle Schaeffer January 15, 2022 - 12:12 PM

I haven't watched seeker in probably 6 years. I remember some of my teachers would show this YouTube channel in class. I remember when it used to be dnews.