Why can people last longer without food than they can without water? Food has water in it. Does this not factor in to survival?
In: Biology
After oxygen, water is the most critical chemical for us to live. ALL life exists in water. The chemical reactions that compose biology take place in water. So we have to maintain plenty of it inside. Unfortunately, a bunch of things our bodies do tend to leak water out of it. Our liver kidneys filter junk out of our bodies and and use water to transport it away via urine. When we breath, water leaks out of our lungs and airways as vapor. When our bodies need to cool down, they leak water through our skin so it cools us as it evaporates. All these things mean we have to keep drinking it to keep our insides wet enough for biochemistry to happen.
Food on the other hand does a lot of work compared to how much we have to eat. We store lots of it short term as sugar in our blood and glycogen stores. We store even more of it long term as fat. Since we don’t constantly need that much of it we can get by on these reserved much longer than we can get by on our water storage.
Edit:
It’s “liver and kidneys” not “liver kidneys”
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