How long can you survive without food?


It can survive without water for only a few days, but it can survive for several weeks if it is deprived of food. This is because your body is extremely resourceful – it can get energy and fuel from its own fat, and ultimately from muscle stores. …

However, the timing of survival without food is not specific. Aside from the fact that there is no reliable scientific evidence to answer this question (researchers have never been able to starve study participants on purpose to study this due to ethical considerations), all people are individual and personal factors such as the initial weight, play an important role. …

Laura Porter / Get Medication Information

How the body fights hunger

The human body's resistance to life without food is impressive given that its stores of glucose (sugar), what your body normally uses as its main source of energy, are depleted within a day after not eating.

After a day without eating, your body releases a hormone called glucagon, which stimulates the liver to produce glucose (a process called gluconeogenesis). This glucose is used primarily to fuel the brain.

On the other hand, your muscles depend on fatty acids from the breakdown of adipose (adipose) tissue for fuel. For about two or three days of fasting, it becomes the main source of fuel for your body.

After all, fatty acids are used to form ketone bodies in the liver. They enter the bloodstream and are used by the brain for fuel, dramatically reducing the brain's need for glucose.

The switch to ketone production in the liver is what allows people to go for a while without eating .

When fatty acid stores are depleted, the only available fuel source is protein (from the muscles). As protein breakdown accelerates, heart, kidney, and liver function are lost, ultimately leading to death.

What affects survival

Based on the limited research that has been done (on people choosing to starve and then go to their doctor, or people who starved against their will ) , there appear to be several factors that affect survival time from hunger.

One of the most important factors is the initial weight of the person. It appears that thin people can generally function normally and tolerate weight loss up to 18% of their body weight, while obese people can tolerate more, perhaps more than 20%.

In terms of exact time periods, studies have shown that in people who are not obese or overweight , fasting causes weakness (weakness) for 30 to 50 days and death for 43 to 70 days. Obese people probably have a longer period of time .

Other factors that can influence the determination of survival time from hunger include:

  • Gender : women live longer than men, even during crises like hunger .
  • Age : Children are at greater risk of starvation .

Complications of not eating

Death is the ultimate universal result of lack of food. Fasting causes numerous complications that lead to death, and the number of affected systems in the body increases with the degree of weight loss .

Some of these complications include:

  • Bone loss ( osteoporosis )
  • Muscle weakness and wasting
  • I am cold
  • Hair thinning or loss
  • Dry Skin
  • Constipation
  • Menstrual irregularities ( amenorrhea )
  • Fatigue, shortness of breath, and paleness from anemia .

Get the word of drug information

Many people who ask this question are asking it out of curiosity, which can be driven by salvation stories and what-ifs, and the above may never be something that touches them personally.

But if you limit your food intake, perhaps due to an eating disorder such as anorexia nervosa, or due to a very strict diet, these fears can have very serious consequences. Seek the help of a healthcare professional. Your body needs (and you deserve) nutrition to function and thrive.

Frequently asked questions

  • It takes your body some time to turn into muscles for energy. In fact, fasting for 24 to 48 hours can help you preserve muscle tissue, as avoiding food stimulates the production of human growth hormone, which is important for building muscle.

  • Maybe. There are some studies showing that obese people may starve (which generally means eating nothing but water, black coffee, or tea) longer than lean people before experiencing the side effects of fasting.

  • Your body will turn to fat for fuel in about 12 hours. The process will speed up significantly after 16-24 hours of fasting.

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