But do you realize how short that time is?
You can go without breathable oxygen for only a few minutes before losing consciousness and eventually, death.
Water is probably the most shocking, but it is the building block of our bodies. Jews fast from water for 25 hours twice a year, but that is enough time to start showing serious symptoms of dehydration. As we know, the rate of dehydration depends on many factors, which is why so many poor fasters avoid the sun and lay in bed in an air conditioned room on fast days. When it's very hot, dehydration can occur within an hour (never leave children or pets locked inside a car in the summer!).
Severe dehydration includes lethargy, vomiting, and diarrhea, eventually leading to shock and death. Even if you have food, you eventually can't digest it without sufficient water intake.
You can last a few weeks without food, as proven by Ghandi and the prisoners of Guantanamo Bay. But it isn't pleasant. Thankfully, many things are edible if you're hungry enough.
Shelter and heat are the ones people often forget. In many areas, you can survive outdoors without too much danger for a couple of days. However, there is always some level of danger from weather conditions or animals. But in extreme conditions such as the desert or a snowstorm, shelter and temperature control are a matter of life and death.
Keep in mind the Rule of Three:
The"Rule of 3"
- 3 minutes without air
- 3 hours without shelter (in harsh conditions)
- 3 days without water
- 3 weeks without food
Your mileage may vary, but I don't suggest trying it.
This is why disaster preparedness guides recommend planning your supplies for 72 hours (3 days). Most people who will die in an emergency situation, Gd forbid, die within the first 24-48 hours. However, most rescue efforts occur within 72 hours. Aim for 3 days of survival, and probability is on your side.