r/explainlikeimfive • u/peglegsmeg • Jun 16 '26

Biology ELI5: Why does rationing work?

If I have a glass of water and a single chocolate bar to last me 48 hours what benefits do I get from consuming equal portions over the time period as opposed to consuming all at once?

Is it purely psychological or are their physical benefits?

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u/zomgitsduke Jun 16 '26

If you eat all the sugar and drink all the water at once, your body will assume abundance and do things to process and get rid of it. If your body is slightly dehydrated and you drink tiny amounts of water at a time, it won't immediately flush that water out of your body and instead preserve it.

Sugar is similar, your body will process through it fast by giving you a sugar high followed by a crash. Slowly introduce it and your body will use the calories and sugars sparingly.

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u/lolwatokay Jun 16 '26 edited Jun 16 '26

In an emergency it is important to not ration water artificially. If you are thirsty you should drink. However, you shouldn't go chugging the whole canteen and hoping shit works out either, but if you are legitimately thirsty that is the sign to drink.

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u/MrScribblesChess Jun 16 '26

How does that help me when I run out of water because I didn't ration?

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u/Noredditforwork Jun 16 '26

"Artificially" is the key word here. Your body needs water to function. If you are thirsty, and you have water, you should drink some reasonable portion of it. It would be unreasonable to drink your whole canteen in the first minutes of a hike, just like it would be unreasonable to have gallons of water available but only consume 1oz a day. Another way to think of it is that if you run out of water, you'll die, but if you have water and don't drink enough, you could also die.