you need sleep and food to regain energy, what kind of energy is this and where in the body is it stored?


you need sleep and food to regain energy, what kind of energy is this and where in the body is it stored?

In: 53

Well, energy from food is stored short term as sugar in your blood (your blood sugar levels, the thing diabetics tract.) and long term as fat across your body.

“Energy” from sleep is different. It is not the same thing as the physical calories we need as fuel. We aren’t 100% sure why we need sleep yet, but the theory is that our Brain just needs a break. Like a muscle that’s been working out all day or a computer that’s been running for a week straight, things just stop working correctly. Nerves/synapses don’t fire right, signals dont travel all the way they’re supposed to, etc etc. and that the rest our brain gets while we were asleep is essential for it to reset itself and be able to function the best.

Again, we don’t exactly know what the physical/chemical mechanisms are that make us feel sleepy/re-energized before and after sleep, but it is quite clear when looking at sleep deprived individuals that the brain just starts to not function as well.

Its chemical energy from food, mostly it turns into a chemical called a.t.p. (adenosine triphosphate) in the cells for easy break down.
Sleep doesn’t actually give you outside energy (you use less energy while asleep, but it won’t make you less hungry) not sure but I think it just gives your body time to catch up on things.

Our body actually uses energy while we sleep, but very minimally compared with an alert state. Food is energy and that energy is stored in the muscles and liver as glycogen and as fat. We actually create the most ATP when moving and exercising as it’s necessary for muscular contraction and cognitive function.

You actually only “regain energy” by eating.

Sleep allows our body to recover and perform metabolic processes (healing, storing memories, fighting infections, etc.) that our body doesn’t have the resources to do as effectively while we are awake because our body’s resources are devoted to movement and cognition while we are awake.

That’s why, when you get sick, it’s common to go to bed feeling a little sick, and wake up feeling like death because your immune activity increases while you sleep and fills up your lymph nodes with waste products after a long night of battle with the invader.

And have you also noticed that sometimes when studying something, it’s hard to grasp the way you want to but you’re able to recall the information fairly easily after going to sleep? That’s your brain processing the days events and storing information.

In a healthy state, it’s common to feel refreshed after a good nights sleep because your body can devote resources to clearing metabolic waste out of your muscles and blood that cause cognitive and physical fatigue.

You store the energy as fat in your body, and there is sugar in your blood. The energy is literally carbon bonds, your body reacts with O2 and gives out CO2 from your breath (so basically you breath out the food you eat and use for energy). It’s the same type of stuff of when you burn gasoline or wood (those are also from carbon bonds) but different (like gasoline is poisonous to humans).

Sleep doesn’t give you literal energy to do work, just like resting doesn’t, we don’t know why or how it is needed. We do know that people start functioning worse with less sleep though.

Like a lot of these comments are saying it’s sugars. More broadly the specific energy is a carbohydrate. When you eat foods of you look on the health facts it tells you the amount of carbohydrates the food has. These can come in mutliple forms/shapes and chains. Three of the most common are sucrose (table sugar), fructose ( this is the sugar that makes fruit sweet), and glucose. Glucose typically comes in chains called polysaccharides. ( Starch in potatoes is just glucose in long chains). The main sugar your body needs though is glucose. So the body has ways to break down the chains and also convert the fructose and sucrose into glucose. If your body doesn’t need any of thr excess sugars(energy) then it stores it as glycogen in the liver. Glycogen is essentially an insoluble/unusable polymer of glucose. Easy to store and won’t be taken up by cells. Of the body is in need of energy the sugars get taken up by cells and the process of turning that glucose into energy begins. There are three steps to this that are not really important for an ELI5 but essentially they are glycolysis, the citric acid cycle, and oxidative phosphorylation. All of this essentially turns glucose into ATP (Adenosine triphosphate) this is what your cells use for energy. So the answer to one of your questions is, the energy you need is ATP which is made from glucose. Sleep is a little interesting. Like others have said, you don’t use very much energy while you sleep. When your cells use up ATP for energy, that ATP is turned into ADP ( Adenosine Diphosphate) and this molecule is a large contributor to what makes you sleepy. So as you go throughout the day you build up all this ADP causing you to be more tired. There are other systems to cause sleepiness but this is one of them. Caffeine works by blocking the ADP from binding to the receptors that will send the sleepiness signals. So by sleeping you are able to convert that ADP that built up back into ATP so when you wake up you feel less tired and can start your day again. There are plenty of nuances here but I feel this is sufficient for ELI5