In light of current things.
Humans can starve to death within days if they have zero water or food. Humans need nutrition: vitamins, protein, fibre, carbs, minerals, some other stuff. I keep seeing watery soup (I think boiled beans of sorts) given to the people and presumably to replenish both carbs and water the body needs. But what about others nutrients that their body is lacking. What about the water bean soups, carb heavy things like potatoes and yams that keeps the body from completely shutting down before other nutrient deficiencies catch up?
How can humans go so long without proper nutrition and clean water?
Edit: This may be more of a bio chemistry question. Please answer terms of biological/chemical processing of nutrients in the body.
Comments
> carb heavy things like potatoes
This feels like a pop culture nutrition perspective.
Potatoes are a very nutritious and versatile food you can subsist on. If you have potatoes and milk, you have basically a “complete” diet and can live healthily.
There’s a reason Matt Damon lives off of them in The Martian.
Potatoes have protein, fiber, minerals and other stuff.
If you’re fat, you can live on just water for quite a long time. You’re not going to be feeling great and you’re not going to be living well, but you will still be well alive until you run out of your fat and protein stores.
The human body is amazing and it will eat itself before letting itself die. You don’t have energy, your hair won’t grow well, your skin will be bad. But as long as you have water, you’ll probably live until you’re fat and protein sources are depleted.
Without water, you’re gone in three days max.
Editing to say you’re typically gone in three days max, there are always exceptions to the rules, but for most people, three days is the general standard.
The body NEEDS water frequently. But just a tiny amount of food will keep the body from failing as long as it can keep cannibalizing its own muscle tissue.
The human body can just keep converting existing tissue into supplies for vital organs.
Eventually it does reach a point of no return. Where organ damage has become so severe that it won’t be fixed by food but also a point where death hasn’t yet occurred. After that death is likely and even with recovery there are lasting consequences that shorten life span drastically.
You can live a lot longer than you think without eating. It’s the not drinking water that can kill you within days.
I am not knowledgeable enough to answer your question but I want to contribute this. People who are that starved/malnourished may still be alive, but their bodies are not functioning properly. If they are able to survive such famine, their bodies and brains will carry the consequences of starvation for a long time, if not for the rest of their life, due to the extreme measures their bodies had to take to survive.
I’m not sure what you’re asking. The human body needs water and nutrients to function. The kidneys help balance electrolytes and water which is why you can survive without water for a few days (less water in = less urine out and more concentrated). To get energy when you aren’t eating food, you can break down glycogen (short term energy storage) but then you start to break down muscle and fat to get energy.
Nutritional deficiencies from diets that barely give you water and calories to stay alive are expected. There are well documented diseases for any vitamin deficiency that you can google pretty easily
Your body eats the fat it has during starvation.
We just lost a resident who had her tube feedings stop. She wasn’t getting water or food. She lasted 11 days!
I mean beans are carbs? Beans are extremely nutritious. You can live on beans and bought else for your whole life.
It’s water you’d die for want of in a few days, and if your food has water in it, well, that’s enough water to not die. And food has water in it, generally speaking.
Like you’ll die in a few days if all you eat is beef jerky and popcorn, I guess, but if you have bean soup, that’s practically all the nutrition and water you need to stay alive. In a famine situation it’s likely not enough, but it will definitely prevent death.
You can go 3 days without water.
30 days for food.
Read that somewhere.
A person can die in 3 hours if they have zero water (drinking water) or water pulled from their food.
Edit: read my downtrace responses. Don’t be arrogant and think dehydration can’t come for you too.
In light of what current things?!
Because nothing needs proper nutrition to survive.
Think of it as if your body is a car. Car needs gas and maintenance, but often even if your check engine light is on you can go months to years without the problem becoming serious enough to shut down your car. You can run your car on a nearly empty tank as long as it’s not completely empty.
You can survive on poor nutrition, but you won’t be well. You’ll feel like shit, look like shit, be unable to concentrate, etc depending on how little nutrition you’re getting. Your body will even start to consume itself before it shuts down entirely, especially if youre getting some calories, breaking down muscle first and then fat until there’s no longer enough energy stored in your body and coming in through what little you have to keep your heart pumping oxygen to your brain.
> How can humans go so long without proper nutrition and clean water?
We’re used to it, after doing it for a few hundred thousand years. If we couldn’t handle it then Neanderthals would rule the world now.
Humanity’s biggest advance was the discovery of fire and a preference for cooked food.
the average us woman is 60 lbs above the weight where they’d get into an unhealthy low weight. Very rough back of envelope calculation that’s enough to go 100 days without food.
(depending on how active/how much of that excess weight was fat)
The average us man has 75 lbs of excess weight (but they are taller/burn calories faster)
> Humans can starve to death within days if they have zero water or food.
This is simply not true. They can die from lack of water in that amount of time, but would not starve unless they were severely starved beforehand – in which case saying they can starve in 3 days doesn’t make sense.
Ignoring the fact that you don’t need the best nutrients to live, your post implies that “watery soup” doesn’t have nutrients. Beans and potatoes have tons of nutrients. They just also have a lot of carbs. When you make them into a soup, it’s just diluting all those nutrients. It’s all literally in the water.
You can get by for a long time as long as you have the right combination of core ingredients. This is why Rice+Beans is so popular. Potatoes are also almost everything you need, which is why they are a good option when paired with 1-2 other things. The main issue with potatoes-only is the sheer quantity you need to eat if you want to get enough of everything. Fat, calcium, and a few vitamins are the main issue, which is why dairy (butter/milk) is a common potato pairing.
As long as you have enough of the staple foods that give most of what you need, you can get by only occasionally eating a bit of other foods to fill in the gaps, and you can go for a pretty long time before a deficiency becomes a major issue. Like weeks, months. Easily years if you can just occasionally supplement whatever is missing from your staple-food-of-choice.
Rice & Beans: you eventually need some Vitamin C or you’ll get scurvy. Potatoes: plenty of vitamin C; there’re accounts of people surviving 1+ years on just potatos, especially if you combine white and sweet potatos. Vitamin A becomes an issue alongside fat. B12 is an issue if you go for a long time. Those micro nutrients aren’t things you need to top-off every day, you just need to have enough in your system over time before you run low.
The human body can survive without food for weeks and without water for only a few days by using stored energy and slowing down its functions to conserve resources.
The body has stores of energy (like fat) that it can use, so it can survive without food for a while. It’s like running a car on reserves until you can refuel!
It cannot.
Biochemistry is clear. You are loosing water and burning nutritions – all the time. The rate depends on many factors. Temperature, humidity, metabolism activity etc.
If you are loosing more than gaining – you are in deficit. Losing just 5% of your body water – you severely phisically impaired. 10% your body cannot maintain blood pressure, kidneys fail, you can even fall in coma. Anything above that is potentially fatal. As a rough rule of thumb you can think of body water as 50-60% of weight. So if you are 60kg female, losing just (6050%10%) 3 liters of your total body water can be fatal. Thats very easy to lose in a single day under high heat conditions or intense metabolic activity.
With nutrition its much less intense, and much more complicated as body has some backups, it strongly depends on what exactly you will be missing. It ranges from weeks (B1) to months.. assuming lack of micronutrients till first symptoms appear.
So people inevitably need access to water. Dirty water is ok, we are living in 2025, most people are not so dumb that they would not be able filter it trough anything available (cloth, sand.. ) and boil it for few minutes. This makes it safe in 99.99% unless its contaminated with chemicals..
There have been people who have done diets with no food for a year under doctor observation and only supplements. They lose 1-200lbs. We store a lot of energy.
Humans can go over a month without consuming a single morsel of food.
And you can go days without a sip of water if you were not sweating and just laying there.
Assuming you were getting at least some calories, and at least a decent amount of water, you could go many months, to years before finally succumbing.
A guy named Angus Barbieri, fasted for 382 days under medical supervision. He essentially only consumed a bit of nutritional yeast, and vitamin supplements.
He ended up losing over 200 pounds.
Its worth noting he was laid up in a bed the entire time.
2 minutes without air
2 days with out water
2 weeks without food
Put very, very simply:
Water molecules are absolutely vital for almost every chemical process that happens inside your cells. Think about those processes as like your cells “cooking” chemicals to do their jobs. Water is required for almost every single one. Your body CANNOT generate water, so you can die of thirst relatively quickly.
Food breaks down into lots and lots of different chemicals.
Some of these are only needed in small amounts, or do things that are nice-to-have but take a long, long time to cause damage if they aren’t done. Think about these like emptying a trash can. You can ignore it and let trash pile up for a long time before it creates a problem that gets a house condemned.
Others (like carbohydrates) are important, but your body stores a lot of them. So when your body starts to run out, it starts tapping in to those stores. This is inefficient, and can cause a lot of nice-to-haves to start hurting or misbehaving. But it takes a much longer time to run out of those stored chemicals than it does to run out of water.
One way to look at that is that water is kind of like a pizza. It’s big. It takes up space. You can’t do much to fit it in a smaller space. So if you need a pizza a day to stay alive, you have to carry pizza boxes, and since they’re so bulky you can’t carry very many of them. In this analogy food is kind of like… clothes. They take time to wear out. You can “carry” more by wearing layers. You can also put them in a bag that you squeeze really tight and tie up that way so they take up less space. They’re lightweight and not as bulky so you can carry more. But every time you want a clean shirt you have to untie that bundle, take out the shirt, then smoosh and retie the bundle, so it’s not easy and you’d RATHER just keep being given clean shirts with your pizza.
Your body eats itself when you dont get enough food. The body is very good at storing what it needs like minerals in your bones, fat and protein in your muscles. The theory is that it comes from when humans where primitive nomads and didnt have access to a varied diet but came across the key necessary resources over time. Thats why we crave food thats fat, salty and full of sugar because this was a rare resource and you ate what you could when you came across it.
The body has a limited storage of water though. Thats why its more critical to drink than eat.
Fun fact: when woman produce calsium-rich milk when breastfeeding they need to make sure they get enough calsium in their diet, otherwise the body will steal calsium from their bones and weaken the bones over time.
Humans are 90% water. We need water. You won’t live long without water. Almost all animals experience seasonal cycles of food availability, and adapted around that. The oddity is that we no longer have that same seasonality.
Historically, you would have lots of fruits available to you in the late summer, early autumn – and would have to store others over the winter as best you could. Winter was historically a time of low nutrition, with people mostly living on grain and preserved meats, preserved vegetables etc.
The ability to get a fresh tomato in January is a very, very modern innovation – a hundred years ago, you had to wait until July to get a tomato.
Rule of 3s
3 minutes without oxygen
3 days without water
3 weeks without food