Campfires need wood to release heat, cars need petroleum to move, and you need food to fuel every aspect of your life.

So what would happen to your body, right now, if you suddenly stopped eating food?

To understand what happens without food,

we first need to understand what happens when you eat.

It starts with the sun, who's energy is harvested by photosynthesis and plants

We then consume that stored chemical energy,

either directly from eating plants like a tomato

or by eating an animal like chicken that has eaten a plant like grains.

If we take a hamburger as an example, you absorb fats from the lipid-filled sauces, proteins from the beef patty, and carbohydrates from the starchy bun.

And it's your digestive system using processes like chewing, gastric acid, and enzymes to break the food into small enough molecules that you can then absorb into your bloodstream.

Any excess glucose is stored in the liver and muscles as glycogen while some are converted into fats.

you can visually see some of the fat stores in the pudgier parts of your body.

There are around 37 trillion cells in your body and you start to really

harvest the energy from your food in the mitochondria of your cells.

This is where glucose and fats have been broken down into Acetyl CoA

and now go through the citric acid cycle

where they're modified continuously to release tons of energy carrying molecules.

The energy from these molecules are then used to pump protons

into a layer of the mitochondria that becomes so dense with protons

they need to diffuse back into the less busy space

and do so by going through a protein called ATP synthase.

As a result ATP is created, the most important energy source in your body.

You use around 10 to the [power of] 25 molecules of ATP everyday.

When this ATP is hydrolyzed to ADP in your body,

the bond breaks releasing energy for things like electrons forming bonds

and essentially creating all aspects of your ability to live.

If you stopped consuming food, within 6 hours your body will be breaking down glycogen into glucose

and fat into acetyl CoA to keep your biological processes at work.

And this is quite normal, but after 72 hours,

your body will need to start breaking down protein in order to synthesize glucose from amino acids

otherwise your brain will starve.

This is because fats used for energy can't cross the blood-brain barrier.

With no vitamins and minerals being consumed, people might start to get sick within a week.

After several weeks of starvation, fat stores become depleted, and all that is left for energy is proteins.

At this point essential proteins for survival, like antibodies used to fight infection

or muscle proteins used for strength, are now being used to make glucose.

And this loss of protein leads to severe illnesses.

Death can come as short as 3 weeks to 70 days,

commonly from a heart attack due to the tissue degradation of the heart, diaphragm, and body.

A factor in how long you live is how hydrated you stay

and also how many fat stores you had to begin with.

Although it's pretty amazing to think that if you did stop eating today

you could potentially live for another 70 days,

but please, don't try this at home.

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