To fast is to abstain from all or some kinds of food or drink. Fasting has been practiced in many religions for thousands of years. Water fasting is a type of fast that restricts all foods and beverages except water. In recent years, it has become a popular way to lose weight quickly, but this practice offers several other health benefits. That said, there are some risks involved, so a water fast may not be suitable for everyone. 

Several studies found that water fasting may reduce the risk of chronic diseases and stimulate autophagy, a process that helps the body break down and recycle old cell parts. Human studies on water fasting are quite limited, so more research is necessary to determine the full benefits. When the body perceives environmental stress, such as restricting food, it adjusts activity of genes relevant to defending the body from stress. That changes that occur truly depend on how long you fast. 

What Is A Water Fast?

A water fast is a type of fast during which you cannot consume anything besides water. Typically, a water fast lasts 24-72 hours and you should not follow a water fast that lasts longer than 72 hours without medical supervision. The main reason that people engage in a water fast is to improve their health. Popular diets like the lemon detox cleanse are modeled after a water fast, but you get to consume a mixture of lemon juice, water, maple syrup, and cayenne pepper during that detox.

How To Do A Water Fast

Although there are no scientific guidelines on how to start water fasting, it is relatively straightforward. People with gout, types 1 & 2 diabetes, or eating disorders, in addition to older adults, pregnant people, and children should not do a water fast. If you have never done a water fast before, you should spend three to four days preparing your body beforehand. Eat smaller portions for your meals or consider eating intermittently in the days leading up to your fast. Most people generally drink two to three liters of water per day during a water fast. It is possible to feel weak or dizzy during this time, so try to do it when you have days off and can rest. Read on to learn more about the benefits. 

May Help Reduce Blood Pressure

According to medically supervised water fasts, people with high blood pressure were able to lower blood pressure levels. In one study consisting of 48 obese or overweight people, water fasting for an average of 17 days under medical supervision reduced systolic blood pressure. Another review found that water fasting significantly reduced blood pressure levels and body weight in people with high blood pressure. Although more research is necessary to evaluate whether or not short-term water fasts reduce blood pressure, initial research is promising. 

May Reduce The Risk Of Chronic Diseases

Some evidence indicates that water fasting may reduce the risk of chronic diseases like heart disease, certain cancers, and diabetes. Research suggests that water fasting may protect that heart from damaging free radicals. Additionally, a 2013 study followed 30 healthy adults who did a water fast for 24 hours. After the fast, they experienced significant reductions in blood triglycerides, a risk factor for heart disease. Several animal and human studies found that water fasting may suppress genes that aid the growth of cancer cells. 

May Promote Autophagy

Autophagy is an integral mechanism for maintaining optimal health. During this process, the body recycles cellular components, like amino acids, to make new proteins and mitochondria, which ultimately makes new energy for the body’s cells. Several animal studies suggest that autophagy may protect against Alzheimer’s disease, certain cancers, and heart disease. Other animal studies consistently found that water fasting promotes autophagy, and that autophagy may extend longevity. All that said, few human studies on water fasting and autophagy exist, so more research is necessary.

May Improve Insulin And Leptin Sensitivity

Both insulin and leptin are hormones that affect metabolism. Leptin helps the body feel full, while insulin helps the body store nutrients from the bloodstream. According to research, water fasting may make the body more sensitive to leptin and insulin. Greater sensitivity ultimately makes these hormones more effective. Being more sensitive to insulin makes the body more efficient at reducing blood sugar levels. Higher leptin sensitivity may help the body process hunger signals more efficiently, which may reduce the risk of obesity. 

The Risks Of Water Fasting

Although water fasting may have certain benefits, it does come with some health risks. One of the risks is that you may lose the wrong type of weight. A water fast restricts calories, so you can lose a lot of weight quickly. Unfortunately, most of the weight you lose in the beginning comes from water, carbs, and even a small portion of muscle mass. You may also become dehydrated during a water fast, which sounds too strange to be true. The reason for that is because about 20-30% of your daily water intake comes from the foods you eat. If you drink the same amount of water and are not eating food, you may not have enough water in the body. Dizziness, nausea, headaches, constipation, and low blood pressure are common symptoms of dehydration. 

As mentioned earlier in this article, water fasting is not for everyone. People with gout, eating disorders, and types 1 & 2 diabetes should not do a water fast without first seeking medical advice. A water fast may aggravate these conditions and worsen symptoms.

Vincent Stevens

Vincent Stevens is the senior content writer at Dherbs. As a fitness and health and wellness enthusiast, he enjoys covering a variety of topics, including the latest health, fitness, beauty, and lifestyle trends. His goal is to inform people of different ways they can improve their overall health, which aligns with Dherbs’ core values. He received his bachelor’s degree in creative writing from the University of Redlands, graduating summa cum laude. He lives in Los Angeles, CA.