Dry Fasting vs. Water Fasting: Risks and Benefits

author avatar Dr. Eric Berg 01/29/2024

There are many health benefits of fasting. It can help you achieve a healthy body weight and improve your overall health. 

Dry fasting and water fasting are two common fasting methods. Dry fasting means you refrain from both food and water, while water fasting allows you to consume only water for the duration of your fast.

Let’s take a look at how to get the benefits of fasting without any negative side effects.

fasting diet

Benefits of fasting

Fasting is incredibly beneficial if done correctly. 

Here are some of the benefits of fasting:

  • Brain cell regeneration, which improves memory and cognitive function

  • Increased mitochondria provide the body with a tremendous amount of energy

  • Autophagy, which allows the body to repair damaged cells 

  • Enhanced stem cell production

  • Decreased inflammation

  • Decreased tumor growth (polyps, cysts, tumors, and fibroids)

  • Increased antioxidants 

  • Improved resistance to stress

  • Weight loss

  • Reduced water weight 

Some worry about losing muscle during a fast. However, fasting stimulates human growth hormone, which protects the body against lost muscle. 

This means that while fasting, your body will only burn your fat tissue, not protein. Protein and muscle are only used for fuel during periods of starvation. 

Autophagy is one of the greatest benefits of fasting. You don’t necessarily need to do a prolonged fast to achieve the benefits of autophagy. 

Doing intermittent fasting—time-restricted feeding with one or two meals a day—allows you enough time to get into a state of autophagy. 

During autophagy, your body recycles damaged proteins that are involved in metabolic processes and enzyme production important for every function in the body. 

Dry fasting vs. Water fasting 

Let’s take a look at the differences between dry fasting and water fasting. 

What is dry fasting?

Dry fasting, or absolute fasting, involves refraining from consuming both food and water. 

If a person is soft dry fasting, they can still use water for things like brushing teeth and washing hands. During a hard dry fast, you avoid exposing any part of your body to water. 

The benefits of dry fasting can be seen in people who participate in religious fasting. 

Ramadan fasting is an example of a dry fast. During Ramadan, people do a dry fast from sunrise to sunset. This practice is typically done for spiritual benefits but comes with health benefits as well.  

The following health benefits have been observed in people doing a dry fast for Ramadan:

•Decreased cytokines, which reduces inflammation

•Increased macrophages, which support the body’s immune system—macrophages consume bacteria, microbes, and viruses 

•Increased microbiome (friendly bacteria help protect your body from bad bacteria) 

•Increased capacity to deal with stress and DNA damage from oxidative stress

•Prevents free radical damage, offering you protection from chronic diseases

One study published by the European Journal of Clinical Nutrition followed a cohort of workers in Indonesia who were fasting for Ramadan. These workers saw lowered BMI and lowered blood pressure at the end of their 29-day fast.

A dry fast is more stressful on the body than a water fast, so you could potentially get better results—although there is no data showing that a dry fast is better. 

If you want to do a dry fast, it’s best not to go longer than a day to avoid negative side effects.  

wet fast

What is water fasting?

A water fast or wet fast involves not consuming any food, coffee, tea, or supplements—only water. Although water fasting has many of the same benefits as dry fasting, water fasting still has potential drawbacks.

According to Dr. Berg, “The food that we eat is so mineral-deficient and vitamin-deficient, and our bodies do not have the mineral reserves to go a long period of time without food.” 

Millions of people are living with mineral deficiencies, which can be especially problematic when fasting. 

Water intake allows you to fast for a longer period of time. However, without electrolytes, vitamins, and minerals, you may still experience symptoms of dehydration and mineral deficiencies. 

In this study, published in the National Library of Medicine, participants completed an 8-day water fast. They experienced several positive outcomes after the fast, but they were low on calcium, sodium, magnesium, and potassium. If the participants were taking electrolytes during their fast, this might not have been an issue. 

The dangers of dry fasting and water fasting

While fasting has many benefits, there are some negative side effects that you should be aware of. If you have mineral deficiencies going into a fast, you are more likely to experience negative symptoms. 

Weakness, issues with your digestive system, and feeling faint or fatigued are all common side effects of fasting. Prolonged fasting of only 48 hours can lead to fainting. 

In severe cases, prolonged fasting can lead to dehydration, ketoacidosis, heart problems, heart attack, and even death. 

Before jumping into prolonged fasting, do periodic fasting and increase the length of the fast gradually. 

For example, try a 24-hour fast first and a 36-hour fast a few weeks later. Follow your body’s cues and eat when you feel it’s necessary. The more fat cells that you have, the longer you may be able to fast.

What you eat before and after you fast is going to make or break your success. If you consume junk food and carbohydrates, this will greatly inhibit the health benefits of fasting. 

To experience benefits from fasting, you should still eat healthy before your fast, focus on a healthy lifestyle, and exercise regularly.

Keto-friendly foods are ideal to provide the body with plenty of vitamins and minerals to support the body during your fast. You can also achieve many other health benefits by following a keto diet, especially if you want to lose body fat.

Pregnant women and breastfeeding women should avoid prolonged fasting. 

If your goal is to increase your body weight, calorie restriction from fasting may not be the best choice for you. 

vitamins for fasting

Why you need vitamins and minerals while fasting

When you’re fasting, your body needs vitamins, minerals, trace minerals, and omega-3 fatty acids. This is especially true when you’re doing prolonged fasting. 

Vegetable broth is a great way to get these vitamins and minerals! To make homemade vegetable broth, simmer your vegetables for 90 minutes and then strain off the liquid. This long simmer time breaks down the fiber in the vegetables, depositing the minerals in the liquid. 

The following organic vegetables can be simmered together to make a nutritious vegetable broth to drink while fasting:

  • Kale

  • Swiss Chard

  • Celery

  • Parsley

  • Radish

  • Ginger

  • Onion

  • Garlic

  • Turmeric

  • Leeks 

  • Endive 

  • Peppers

  • Cabbage

  • Bok choy

For a healthy fast, drink around 2.5 liters of vegetable broth per day. This broth will help replenish minerals, allowing you to feel much better while you fast. It can also help curb your appetite and promote weight loss while you’re on a ketogenic diet.

Green tea is an excellent way to increase your antioxidant level and energy levels while fasting. 

Electrolytes like potassium, magnesium, sodium, and chloride are vital in maintaining healthy energy levels, especially when fasting for an extended period of time.

You’ll know that you're doing your fast correctly if you still have the energy to exercise without feeling faint or weak. 

It’s important that you don’t break your fast with a huge meal—increase your calorie intake slowly to avoid re-feeding syndrome.

You can also take nutritional yeast for B vitamins, and be sure to drink plenty of water during a prolonged fast. 

drinking electrolytes

Key takeaways

To achieve the amazing benefits of fasting, make sure you’re doing it the right way. Ensure that your diet is healthy before you begin fasting so that you have adequate mineral stores to last you through your fast.

Consume electrolytes, sea salt, green superfood powder, and vegetable broth to replenish lost vitamins and minerals. 

To avoid regaining lost weight after a fast, continue a healthy diet and exercise routine. Try keto and intermittent fasting as a sustainable way to get healthy and lose weight. 

Always consult with a healthcare provider to determine if fasting is right for you. 


1. What is water fasting?

Water fasting involves refraining from consuming any food or beverage except water for an extended period of time. 

2. What is dry fasting?

Dry fasting involves refraining from eating food and drinking water. If you’re doing a hard dry fast, you won’t use water to brush your teeth or wash your hands. A soft dry fast allows you to use water for cleaning purposes or hygiene purposes, but not for drinking. 

3. Why shouldn’t you dry fast?

A short dry fasting routine can be beneficial, but a dry fast should not be prolonged. Ramadan fasting and other types of spiritual fasting are a form of intermittent dry fasting, which is beneficial for short periods of time. An extended dry fast can lead to severe dehydration, weakness, and even death. 

4. How many hours can you do dry fasting?

Prolonged dry fasting shouldn’t be done for more than 24 hours. A shorter dry fast is typically more beneficial to your health. 

5. Is dry fasting more beneficial?

There isn’t much data comparing water fasting to dry fasting. Dry fasting places your body under more stress, which can lead to more noticeable results. 

Try both water fasting and dry fasting to see which fasting routine works better for you. Remember the risks and avoid dry fasting for extended periods of time. 

6. What are the dangers of water fasting?

Water without minerals does not supply you with the electrolytes that your body needs to survive. Even a 48-hour water fast without electrolytes can cause fainting episodes. Electrolytes are vital for your nerves, cells, and muscles. 

7. What are the dangers of dry fasting? 

The dangers of dry fasting are similar to the dangers of water fasting. However, there is also a risk of dehydration. Without water or efficient mineral stores, you may experience weakness, dizziness, or digestive issues. 

8. How long can I do water fasting?

Without electrolytes, a water fast is not sustainable for longer than 48 to 72 hours for most people. When you add in the necessary vitamins, minerals, trace minerals, and electrolytes, you’re able to fast for a lot longer. Some people successfully complete a 30-day water fast without negative side effects. Always increase the length of your fast gradually—start slow.

9. Can I take vitamin and mineral supplements while fasting?

Yes! In fact, you should. Consuming electrolytes, green superfood powder, and vegetable broth are ideal for a healthy and beneficial fast. 

10. Can dry fasting make you dehydrated? 

Prolonged dry fasting has the potential to make you dehydrated. Limit the time you spend dry fasting to reduce this risk.

11. Should I drink water while fasting?

Absolutely. Water—along with electrolytes, vitamins, and minerals—are essential for a healthy fast. 

12. Can you lose weight by dry fasting?

Yes! Dry fasting, water fasting, and fasting with supplements all promote weight loss. 

13. Can a dry fast damage your kidneys? 

A short dry fast will not affect kidney health. A longer dry fast without electrolytes or water can cause symptoms of acidosis. Avoid dry fasting for longer than a day. 

14. Why is my urine yellow while dry fasting?

Dark yellow urine can signify dehydration, but it can also mean that there are ketones in your urine.

15. Do I need electrolytes while fasting? 

Absolutely. Electrolytes are essential to your health during a fast. Electrolytes provide the body with the minerals it needs while you’re fasting. 

16. Can I have lemon water while water fasting? 

Yes! Lemon water is an excellent drink to support the body while fasting.

17. Can I drink water while doing intermittent fasting?

Yes! Water does not spike insulin, so it will not interfere with intermittent fasting. 

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