Where does lost weight ACTUALLY go?

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[blazer]

There should be a full long video on this topic, weight gain, fat, obesity can also be included.

[cynthiaahern]

You learn something new every day. Many many people including me don't understand how the body actually works. Now I am going to go down the rabbit hole on this topic

[chriscarver]

Registered dietitian with a background in exercise science (kinesiology), here.

People focus too much on the energy (kcal) being burned during exercise for weight loss, but in reality, the vast majority of extra energy burned from physical activity occurs AFTER engaging in physical activity, while the body is in recovery - specifically, this is referred to as EPOC - Excess Post-exercise Oxygen Consumption.

For up to a few hours after exercise - particularly more vigorous exercise, but to a lesser extent with more mild physical activity - most of the body's metabolic processes, as well as muscle recuperation, require a significant increase in oxygen consumed. (In this case, "significant increase" is at the cellular level and may not be noticeable for the person experiencing it; however, they may also notice that they're breathing a smidge deeper or faster for few hours afterwards, relative to baseline breathing.)

The increased oxygen consumption ALSO results in increased carbon dioxide released (exhaled), since the body requires two-directional gas exchange to remain balanced. As pointed out in the video, carbon dioxide is often sourced from metabolized fats (but also carbohydrates and proteins).

Additionally, we can't forget that MUSCLES MATTER. Pound for pound (or kilo for kilo), muscle burns FAR more energy that fat mass. Muscle mass requires a LOT of energy to maintain - even in a resting state. By having more muscle mass, the body naturally burns more energy (kcal) throughout the entire day.

[dominiklehn]

It should be noted that you ALSO lose water through breathing. It is a significant amount even, many people underestimate just how much water we can lose just by breathing out the hot, humid air our lungs need to function

[RRonco]

My middle school gym teacher (shout out Mr. L!) taught us that fitness starts with good sleep. He was absolutely correct!

Weight management and preservation of muscle mass is so much easier with great sleep. Being a natural night owl makes it tough, but I work hard to prioritize my sleep. Makes an enormous difference!

Mr. L was a real one. When one of us would fall asleep in some class or another, he'd let us take an emergency nap on the mats. We were growing, gangly, total goofballs, always behind on sleep, & Mr. L knew what we were going through. He was a great coach, too, as well as a teacher. They named the gym after him when he retired!

[carlosmohedano]

"Crying at the gym" got me rolling for real 😂😂😂

[Colorado-Coyote]

So you're telling me every time I have a panic attack I'm loosing wieght!!!

[kinexkid]

Using the chemical formula provided, the molecular weight that you lose in CO2 is 2.58 times heavier than the molecular weight of the amount of H2O lost, so you're literally exhaling most of your weight!

[thovo]

Exercising isn't the major factor that directly help you lose weight, it's the increase in metabolism through exercising that does it.

[agentp]

Trees take CO2 from the atmosphere and convert it into solid cellulose fibers. Which happens surprisingly fast if you consider the amount of CO2 available. The tree doesn’t extract mass from the soil and create a cavity. It’ll extract nutrients but it doesn’t make up the bulk of the tree’s mass.

[christopherhall]

A simplistic explanation, but correct in all the right ways, if there was more of this on Youtube, the world might be a better place.

[Hi_Im_Akward]

Its pretty solidly proven that exercise is not a great answer for losing weight. You should exercise for a host of other reasons, but we biologically are designed to conserve as much energy as possible. Exercising when you normally dont can't "shock" the system into offloading calories as a way to deal with a change in energy needs but there are a lot of ways the body compensated, a lot of ways that we don't fully understand.

Something people seem to fail to understand is that the majority of calories burned in a day are from your body literally trying to stay functioning. Basal metabolic rate. It costs energy to think, sleep, breath, basically anything you do.

Thats all to say the most effective peoven method is to eat within a calorie deficit. And the most sustainable proven method is to be in a very mild calorie deficit for a long period of time. And as your body changes (be it from exercise, muscle gain, fat loss, etc) your should recalculate it every few months in order to make sure you are within the correct range. Also anyone who is trans should calculate it according to their hormones and not necessarily their sex because HRT can cause massive differences in body composition and metabolic rates.

[Mouradin]

From an evolutionary perspective it also makes sense. Recent diets and eating are only (no more than) a couple hundred years old at best. It would make sense that from a physiological perspective our bodies would utilize nutrients better by storing them as extra fat for times of strife or hard to access food.

It also more than likely relates to economic principals as it used to be only royalty and people with money could afford to be overweight (status) and now it’s reversed that low income earners are more likely to be overweight as they have less access to healthy foods, work longer hours and have less time to devote to practicing good health

[joshspringsteen]

Mass definitely can be destroyed, E=mc^2 is the mass energy equivalence principle.

[dannykraeger]

I burst out laughing when you added Homer screaming lol

[babybirdhome]

Not to mention that as you exercise, your lungs and breathing get more efficient, and so do your muscles in processing the fuel they use for their energy.

What I’ve learned is that exercise isn’t for losing weight - controlling what you eat does that. Exercise is for improving your health and allowing your body to make more efficient and effective use of what you eat so you can get by with eating less (and being healthier and having an easier time exercising to be more healthy). Controlling calories is how you control weight, and exercising will only get you so far (and can have a rebound effect if you don’t also change your diet).

The complicated part about your weight being controlled by what you eat is that how your body processes what you eat depends on genetics, general health, and your gut biome. Identical twins can eat identical meals and one can gain more weight than the other because they’ve developed different gut flora which affects what your body is even capable of processing and what it can extract from what you eat. This results in some people having a very difficult time losing weight and other people having a difficult time gaining weight. One of the most extreme examples is a girl named Lizzie Velasquez who has a YouTube channel who has an extremely rare condition she was born with where she has no body fat at all and she can’t gain weight. She has to consume over 10, 000 calories per day just to stay alive and she weighs almost nothing. If I consumed that much, by comparison, within a few years I would likely weight over 1, 000 lbs, if I didn’t just outright die. So while it’s true that your weight is mostly controlled by the number of calories you consume, it’s not as simple as a straight X calories per day equals Y lbs of body weight like people tend to think it is. It’s different for every single person, and for some people, it’s significantly different.

Then there’s the fact that everyone’s dietary needs are different, too, so it’s not even just a matter of eating what someone else ate to lose weight - that diet has to actually fit your own body’s particular needs, too. It isn’t always willpower that makes people overweight - it’s a lot more complicated than that, which is one of the biggest reasons not to fat-shame people. If you’re not their physician, you’re not really in any position to say whether it’s a problem of willpower or laziness or some other character flaw - many times the people who struggle the most are trying a lot harder than the people criticizing them ever have.

[NelsonBrown]

Also, your houseplants' carbon comes almost entirely from the air. Your burned fat is what grows your plants.

[sw]

I lost weight just by changing my daily diet, sticking with it, and maintaining a moderate exercise routine - cardio, weights, and core strength. All that’s left now is stubborn belly fat that won’t go away 😪😪😪

[ferret]

Ive genuinely had this thought before in the shower and it freaked me out. Eventually, it left me. Thank you for reminding AND answering me!

[StefanieMoore]

Thank you for the explanation! I have asked myself this question so many times