Water Fasting Side Effects

Water fasting can be bad for your heart.
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The water fasting diet is a dangerous way to lose weight. While there are healthy fasting diets, only consuming water for days is not safe.

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Often water fasting results in weight loss but only at a severe cost to your health. There are healthier ways to go about losing weight. And if fasting is of particular interest to you, try an intermittent fasting diet, they've been proven for years to work.


The Water Fasting Diet Breakdown

The water fasting diet is a fad diet that may have crossed your path. According to those who tout its benefits, fasting while drinking only water will do great things for your health. And that's how the water fasting diet works: You don't eat anything for at least five days, sometimes as long as 30 days. Instead, the water fasting diet requires that you stick to only water.

If that sounds impossible, that's because this diet is too extreme​.​ It may sound great, when you hear people telling stories about how amazing they felt after not eating for days. However, water fasting to lose weight is nothing more than a starvation diet masquerading as a weight loss plan. Consuming only water for days at a time is harmful to your health.


Whatever you've heard about the amazing results the water fasting diet will get you, you may never experience them. And if you do, it may come as a serious threat to your health. This is a fad diet, and as such it can have serious negative effects on your body's functions.

Even if you decide to subject yourself to the dangers of this diet, once you stop, you will gain all your weight back and then some because it will slow your metabolism, according to an article in the September 2017 issue of ​Perspectives on Psychological Science.


Who Should Go On It?

Before going on a diet, it's essential to understand the possible side effects it may have on any population.

Most diets produce different results for different people. Starving yourself for days however, will have a similar response for everyone. The effects can come quickly, starting with the oncoming of stress and the feeling of exhaustion. And if you continue for too long, you will experience malnutrition.

While there are benefits to intermittent fasting diets, this is not one of those diets. The water fasting diet requires complete abstention from food for days, sometimes over a month. It's not healthy. And this kind of diet's particularly dangerous for people who struggle with eating disorders.


Read more:What Are the Effects of an Unhealthy Diet?

What Are the Risks?

There is some truth to this diet causing weight loss. Reducing calories will cause your body to burn fat, according to a study published in Cell Metabolism in the January 2014 issue. The dark side to the water fasting diet is that you aren't just reducing your calories; you're eliminating all of them.

And your body needs those calories. Consuming too few calories for too long can cause damage to your heart and even lead to cardiovascular diseases. It can cause problems for your intestines, to the bloating of gut to constipation. You may even find that your hair starts to thin or to fall out easier.

While there are healthy ways to reduce your calories through intermittent fasting, the water fast isn't one of them.

Read more:How Many Calories a Day is Considered Starving?

A Healthy Type of Fasting

There are several different healthy plans for breaking up your fasting. Some people choose to fast for one day per week, and there are those who fast during the night and early hours of the morning.

A study in the June 2014 issue of Integrative Medicine: A Clinician's Journal looked into the side effects of fasting regimens. The benefits of fasting take days to kick in, so, while fasting once a week can add up to the same number of hours of fasting, a day isn't long enough for the benefits to kick in.

Instead, the study recommends fasting between 5:30 p.m. and 10 a.m. every day for a week to 40 days. Some regimens start with days of complete fasting, beside water consumption, but that type of diet is best done under the direct observation of a dietician.

On your own, a daily fast is best, and don't worry if 14 1/2 hours sounds like too long to go without food — from 5:30 p.m. until bedtime, you can eat foods like apples and almonds. Once you wake up, though, you shouldn't eat anything until 10 a.m. or 12:30 p.m, depending on how long you decide you'd like your fasting period to be.

At any time, whether it's a fasting period or a period when you're free to eat, you can consume as much pure, distilled water as you desire. During the day, when you can eat, try limiting your calories to 1,000, but always listen to your body and talk to a physician if you notice any concerning side effects.

Intermittent Fasting and Weight Loss

As with most diets, there's that desirable side effect of weight loss. And it turns out, intermittent fasting is a healthy way to lose weight. According to the ​Cell Metabolism​ study, humans have fasted for millennia. Many cultures have used it for various functions; most recently, studies have confirmed its health and weight loss benefits.

Fasting results in ketogenesis and promotes significant changes in metabolic processes. These improved metabolic functions assist in the weight loss process. An article in the August 2017 Annual Review of Nutrition confirmed this affect — intermittent fasting improves the metabolism leading to weight loss.

In eight weeks, fasting weight loss can be as much as 8 percent of your weight. An August 2018 article from the National Institute on Aging focused on adults living with obesity. They found that intermittent fasting was particularly effective at helping those adults lose weight. The article did caution that long-term studies are still needed on intermittent fasting side effects.

Intermittent Fasting Side Effects

Besides the health benefits and weight loss, what other side effects are there? It turns out that most of the adverse side effects are pretty mild for adults. And those that were more serious were also uncommon.

A February 2018 study in BMC Complementary Alternative Medicine categorized the negative side effects by intensity. The researchers reported that most of the side effects weren't serious, although you may experience some nausea, headaches, insomnia, back pain and fatigue. Try drinking water to reduce these symptoms and eat if they don't go away.

A slightly more severe side effect is lightheadedness. If you're light-headed, then it's time to break your fast, even if you're supposed to fast longer. It's always best to be safe. The most severe side effect is abnormally high blood pressure, which requires seeing a doctor for treatment.

What's Still Unknown

A study in the April 2015 issue of the Journal of the Academy of Nutrition and Dietetics called for further research into the diet's effect on sleep. Current studies haven't looked at possible negative or positive side effects on a person's sleep.

The study's authors also suggested more research into the effects on physical activity. The schedule from ​Integrative Medicine: A Clinician's Journal​ recommends fasting through the morning. How does that affect your energy and physical activity throughout the day? As with any diet, it's essential that you observe how the diet affects these functions along with the rest of your health.

Only you and your physician can determine whether a diet is right for you.


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