Pouring Water

Fasting diets are currently on the rise when it comes to what's trending. Not eating for 3 days can and will damage your body, and may actually cause you to gain weight as opposed to losing it. Before exploring any diet, it is crucial to know what the risks are.

Read more: Why Trying a Water Fast Is So Risky

The Water Fasting Diet

In a June 2014 interview with Alan Goldhamer, DC, published in the Journal of Integrative Medicine, he describes his own research on water-based fasting. Based at the True North Health Center in Santa Rosa, California, he has personally overseen thousands of patients engaging in therapeutic fasting in a controlled, comfortable environment.

The water fasting diet should not be confused with a simple calorie restriction diet used to shed some extra pounds. It consists of not consuming anything for three days aside from water, which if not practiced with caution, can result in a variety of detrimental side effects on the body.

Goldhamer practices fasting with patients at the True North Health Center under very particular conditions to benefit their health. It is not appropriate for day to day life.


The environment is a key factor in the safe application of water fasting. The body cannot continue as normal when it is consuming nothing but water, as energy levels are not the same. It's important when water fasting to be comfortable and relaxed and never overexert the body.

Not Eating for 24 Hours

A common implementation of fasting in contemporary times is the practice of not eating for 24 hours. One day per week, ordinarily, an individual will fast in the hopes of weight loss or body detoxification. Unfortunately, clinical evidence has demonstrated that 24-hour fasts are not actually the most productive action to proceed with.

Any longer than this, however, and you run the risk of seriously damaging your body. Your body needs food. It's how it produces its energy, as well as keeps it strong and healthy. Without it, you will grow frail, ill and lethargic from a lack of nutrients that your body needs.

According to the National Centre for Eating Disorders in the United Kingdom, potential physical side effects that can emerge from not eating for 24 hours include:

  • Heart and circulation problems: Your heart is a muscle, and if you are not providing your body with energy it will weaken like any other muscle. This can lead to ulcers forming on the legs and feeling of extreme cold in the body where blood cannot flow
  • Bone health: With no beneficial healthy vitamins or minerals entering the body, bone density can be negatively effected resulting in frailty and increased risk of fracture. 
  • Skin health: Though effects can vary, under-eating can result in dry skin and signs of early ageing as the body doesn't have the nutrients it needs to sustain itself.
  • Low blood sugar: Not consuming enough food can lead to a condition called hypoglycemia, where there is insufficient glucose in the blood. This can lead to the heart stopping entirely, and is the leading cause of death in anorexia sufferers. 

Further side effects of fasting for extended periods (such as no food for 3 days) may include:

  • Fatigue: If the number of calories the body is receiving is reduced, the amount of energy it produces will decline too.
  • Hair loss: A lack of food can mean a lack of necessary vitamins and nutrients, which can lead to the breakdown of proteins necessary for hair growth.
  • Recurring illness: Diet has a direct effect on the strength of the immune system, so frequent illness can be a sign of insufficient intake of food.

This list is not intended to scare anybody, but it is exceptionally important that risks are fully considered before considering reducing your calorie intake by any standard, even more so where fasting is concerned.


If you are considering adopting fasting into your diet, consider the 5:2 diet where fasting occurs on non-consecutive days for two days of the week, as opposed to continued fasting. This places undue stress on the body, and will not yield positive weight loss in the long term.

Weight Loss in a Day

A July 2018 study published in the Cureus Journal indicates that alternate day fasting, which is when fasting only takes place on one or two days in a week nonconsecutively, is highly effective in weight loss. However, it is not clear what other effects this has on the body and how detrimental it may be in the long run. Though intermittent fasting can be effective in weight loss, a balanced diet is easier to commit to for the long term.


Intermittent fasting does not consist of abandoning food entirely, but rather restricting calorie intake particularly on two non-consecutive days. Fasting with no food can be highly damaging to the body.

A July 2017 study published in the JAMA Internal Medicine Journal following the diets of 100 obese individuals found no significant benefit or detriment in weight loss through fasting compared to a daily calorie restrictive diet. Lifestyle changes are thought to be the best way to lose weight and maintain the loss, and if weight loss is the goal then fasting should be avoided.

Fasting is not something to practice to lose a few extra pounds, it can be harmful to the body and will not provide long-term results. The majority of the weight will return once normal eating is resumed, rendering any weight loss benefits entirely null.

Read more: 5 Simple Ways to Make Intermittent Fasting Easier

Who Shouldn't Fast?

Fasting consists of depriving the body of food that it would ordinarily expect. Therefore, it's important to consider all of the details of an individual's biological makeup and requirements before embarking on a fast of any kind, medical or religious.

According to the Harvard T.H. Chan School of Public Health, the following groups should not commit to fasting:

  • Those with diabetes: This is because diabetes requires a careful maintaining of sugar levels in the body, and depriving the body of food can severely impinge an individual's ability to keep their sugar levels optimal.
  • Individuals suffering from an eating disorder: If the body is already under stress from conditions such as anorexia or bulimia nervosa, then fasting is not applicable. Consistent and balanced food intake should be maintained in regard to eating disorders.
  • Those taking medication that requires food intake.
  • Individuals going through growth such as children and adolescents.
  • Individuals who are pregnant or breastfeeding.

Finally, fasting should not be adopted by anybody looking for a quick way to shed a few pounds. The National Health Service of the United Kingdom indicates that not only is unsupervised fasting ineffective in creating long-term weight loss, but it can actually cause excess weight gain. This is because depriving the body of food can result in cravings once you are finished fasting, which usually leads to over-indulgence.