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What are the Most Common Fasting Dangers?

Jessica Ellis
Jessica Ellis
Jessica Ellis
Jessica Ellis

Fasting involves a period of time during which a person lives on an extremely limited diet, sometimes consisting of nothing but fluids. Done for a variety of reasons, including as a political message, for weight loss, and for religious observation, fasting can be a dangerous practice that many heath professionals warn against. It is important to get a clear picture of fasting dangers before deciding to embark on a period without food.

While some people are able to survive a fast and feel healthy and revived, others suffer a variety of short-term effects. Nausea, dizziness, painful headaches, and fatigue are all common fasting dangers experienced within the first few days of a fast. Fasting dangers in this early stage can include lethargy and a drop in productivity or job performance. Some fasting regimes are not calorie-free, thanks to the use of juices or special teas, but the lack of solid food on the body may translate to a fast onset of symptoms nonetheless.

Some fasting programs are not calorie-free because they allow juice.
Some fasting programs are not calorie-free because they allow juice.

Increased potential for illness is another of the more serious fasting dangerous. A lack of vitamins and minerals opens the body up for inflammation or illness, and some people develop a cold or flu within days of beginning a fast. Blood pressure typically plummets without food, leading to chills, weakness, exhaustion, and sometimes severe mood swings.

Fasting can impair a person's mental functions.
Fasting can impair a person's mental functions.

After a few days on a fasting program, fasting dangers dramatically increase. The body, which needs sugars to continue normal fasting, begins to feast on bodily tissues to maintain a survivable metabolism. While dieters may hope that the body will devour excess fat, it can also destroy muscle and organ tissue from the kidneys and liver. Prolonged fasting can lead to severe tissue damage, including to the delicate heart muscle system.

Nursing mothers and pregnant women are advised to avoid fasting.
Nursing mothers and pregnant women are advised to avoid fasting.

It is important to note that prolonged fasting can cause permanent damage to bodily systems and even be fatal. There have been instances of death by starvation during fasting, often caused by severe malnutrition. If the body reaches a point where it can no longer maintain itself, recovery may be impossible and death can occur in some cases.

Many health experts strongly recommend avoiding a food-free diet for anyone with diabetes, heart or kidney problems. Pregnant and nursing mothers are also advised to avoid fasting as it will starve a growing fetus or nursing infant of nutrition vital to healthy growth. Similarly, children and teens are often strongly discouraged from fasting as it can disrupt growth and have lifelong effects.

Headaches are often a side effect of fasting.
Headaches are often a side effect of fasting.

Some fasting dangers can be guarded against by taking proper precautions prior to and during a fast. Experts often warn that a fast should only be conducted under careful medical supervision. Spending a week or two slowly changing a diet to be ready for a fast can help reduce early side effects like headache and nausea. Additionally, taking vitamin supplements and ensuring proper hydration can also help the body maintain normal function during a fast.

Jessica Ellis
Jessica Ellis

With a B.A. in theater from UCLA and a graduate degree in screenwriting from the American Film Institute, Jessica is passionate about drama and film. She has many other interests, and enjoys learning and writing about a wide range of topics in her role as a WiseGEEK writer.

Learn more...
Jessica Ellis
Jessica Ellis

With a B.A. in theater from UCLA and a graduate degree in screenwriting from the American Film Institute, Jessica is passionate about drama and film. She has many other interests, and enjoys learning and writing about a wide range of topics in her role as a WiseGEEK writer.

Learn more...

Discussion Comments

anon1000743

Article based on author's opinion without any scientific or even anecdotal evidence -- I'm betting the person in Post 2 who fasts 30 days a year is healthier than the author of the article!

Drentel

If you are on medications then you should be careful about any big changes in the way you eat. Fasting for days could change the way medicines work in your body and then could cause some big health problems. Besides, most directions suggest medicines be taken after you eat.

Animandel

I think if more people read the last paragraph of this article and then fasted based on what it says in that paragraph then there would be fewer people getting sick. At work, there was a group of ladies who decided to go on a fast with fasting juices. They thought that by doing it together they stood a better chance of sticking to the diet.

Some of the women made adjustments in their diets leading up to the fast as is suggested in this article. On the other hand, some women ate as usual right up until the day of the fast, and then they went cold turkey--no solid food whatsoever. As you can imagine, these were the women who suffered the most and they were the ones who did not fast for the entire period they had planned to.

Laotionne

I have a friend whose religion requires her to fast. I don't know exactly how often she has to do it, but all totaled she has to fast for 30 days each year. When she is fasting she eats nothing and I know this has to be miserable. However, she says that not eating for short periods doesn't bother her.

She says that the biggest precaution she has to take is not being as active as she would be if she were on a regular eating schedule. She doesn't do any additional exercise like running or exercise classes when she is fasting because she doesn't have the energy and her body can't afford the extra exertion since she's not eating.

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    • Some fasting programs are not calorie-free because they allow juice.
      By: marcelokrelling
      Some fasting programs are not calorie-free because they allow juice.
    • Fasting can impair a person's mental functions.
      By: Ana Blazic Pavlovic
      Fasting can impair a person's mental functions.
    • Nursing mothers and pregnant women are advised to avoid fasting.
      By: xjrshimada
      Nursing mothers and pregnant women are advised to avoid fasting.
    • Headaches are often a side effect of fasting.
      By: jedi-master
      Headaches are often a side effect of fasting.
    • Nausea is one possible side effect of fasting.
      By: Johan Lenell
      Nausea is one possible side effect of fasting.
    • Children should not engage in fasting because it can affect their physical and cognitive development.
      By: Tatyana Gladskih
      Children should not engage in fasting because it can affect their physical and cognitive development.