Dry Fasting: Will It Kill You Or Heal You?

Medically Reviewed by Dr Babar Shahzad, BSc and MBBS

Abstaining from food for prolonged periods already sounds like a challenge. What about not being able to drink while you fast as well?
As crazy as it may sound, it’s a thing, and it’s called dry fasting.

While people swear by its incredible benefits for health and mental state, most doctors and wellness experts encourage to avoid dehydration at all costs.

So what’s the deal with dry fasting? Sit back and read on.

What is dry fasting?

In case of intermittent fasting, you have to cut off food intake completely. But, drinking liquids such as water, tea, and bone broth is not only allowed, but also recommended.
In dry fasting, you also have to cut off liquid intake in all shapes and forms.

Not being able to eat as well as not drinking any water makes it the most strict fasting method there is.

Although right now it’s gaining popularity because of its health benefits, it has been known in religious communities for centuries.

Millions of people are doing it for a month once a year, actually. During the holy month of Ramadan, Muslims refrain from eating or drinking from sunrise to sunset, which lasts between 28 and 30 days.

Why to some it seems to be a good idea? Let’s find out.

Types Of Dry Fasting 

Intermittent Dry Fasting

Intermittent dry fasting has three main approaches:

  • 16:8 Dry fasting is one of the most popular methods. The only difference from the classic intermittent fasting is that you not only abstain from food, but also from any liquid intake.
  • 20:4 Dry Fasting is quite an extreme approach to dry fasting. It means you can consume liquid and food only within a 4-hour gap per day and abstain from it for the remaining 20 hours.
  • Ramadan Intermittent Fasting or RIF, as the name suggests, is done by Muslims during the month of Ramadan. They have to abstain from food and drink between dawn and sunset.
    The fast usually lasts somewhere between 11 and 16 hours. But In some regions, such as Greenland, where the days during the month of Ramadan are much shorter, the fast can last up to 21 hours.
    Most of the scientific research done on dry fasting is done particularly on Muslims during the month of Ramadan.

Prolonged Dry Fasting

Prolonged dry fasting means fasting for more than 24 hours.
Although  24 hours is where health experts draw the line, some people claim to do relatively regular dry fasts of 48-72 hours. Some experienced dry fasters are claiming to have fasted for as long five days or more. That’s not only hardly believable, but also sounds really dangerous.

Water is essential for every organ in our body to function. Not having water for three days can lead to severe dehydration or even death, so it’s the place to say that we by any chance do not recommend going on such extreme dry fasts. It can lead to serious consequences and health problems, and it’s important to note that.

Absolute Dry Fasting

Absolute dry fasting means abstaining not only from drinking but also from having any contact with the water at all. Not showering, not brushing your teeth, not even washing your hands.
The theory behind it is that some amount of water can be absorbed through our skin, and the goal of dry fasting is to cut out the liquid intake completely.
While some minerals, nutrients, and chemicals can be absorbed through the skin, our skin epidermis is water-resistant, meaning this theory shouldn’t be held as truth.
Going on an absolute dry fast just might make the whole experience even more uncomfortable.

Dry fasting benefits

It is obvious; no one is doing it for their own pleasure. There might be some really striking health benefits that make it even considerable doing.

Improved cognitive function

The main motivation for a lot of people is improved focus and productivity.
Although intermittent fasting is a more popular option, dry fasting may improve cognitive function even more.
A study on 22 women and seven men dry fasting during Ramadan was conducted. Investigation showed that the plasma levels of serotonin, BDNF, and NGF were significantly increased during the fasting month of Ramadan.

Serotonin is an important chemical and neurotransmitter in the human body. It is believed to help regulate mood and social behavior, appetite and digestion, sleep, memory, and sexual desire and function. Lack of serotonin can cause depression and anxiety.

BDNF is a protein which is found in the brain. It helps to support the survival of existing neurons and encourages the growth and differentiation of new neurons and synapses. BDNF is also vital for long-term memory.

NGF is involved in the growth, maintenance, proliferation, and survival of nerve cells. It is, in fact, critical for the survival and maintenance of sympathetic and sensory neurons, as they undergo apoptosis in its absence. However, several recent studies suggest that NGF is also involved in pathways besides regulating the life cycle of neurons.

Weight loss

Since during dry fasting, you’re not consuming ANY calories, this may sound like an obvious benefit.
But it does have some magic to it because it’s incredibly effective in burning fat.

First, dry fasting helps to lose weight because of calorie restriction. All weight loss is achieved through the same equation – you lose weight if you burn more calories than you consume.

Second, fasting is linked to lipolysis, which is basically fat burning.
By lowering insulin and increasing growth hormone levels, it also increases the release of the fat-burning hormone called norepinephrine (noradrenaline). Due to these hormonal changes, fasting increases your metabolic rate.

Third, dry fasting won’t make you lose your muscle mass. Well, at least that’s what a 2016 study says. The study examined 43 Ramadan fasting subjects for 4-5 weeks. The catabolism (catabolic state, which is related to protein loss) was not triggered, but body fat measures have decreased significantly.
Although, it is important to note that weight loss was only a temporary effect, as the weight was quickly regained within one month after fasting.

Fourth, advocates of dry fasting claim it helps to burn three times more fat than regular fasting.
That’s because when our bodies are out of water, they start looking for ways to make it ourselves. Interestingly, our fat is full of water. For every 100 grams of fat, the body can produce 110 grams of metabolic water, while 100 grams of carbohydrates yields only 55 grams of water.
This means that the body intensifies the fat burn in order to make more water.

May improve cholesterol levels

Another study conducted on Ramadan fasting subjects showed incredible results in the increase of good cholesterol.
Levels of high-density lipoprotein (HDL) increased by 30-40%. That is definitely good news as high levels of HDL cholesterol can lower risk for heart disease and stroke.
“Good” cholesterol, absorbs the “bad” cholesterol and carries it back to the liver. The liver then flushes it from the body.

May help treat diabetes

Dry fasting can also help treat diabetes.
Results of a 2014 study revealed that fasting during Ramadan is significantly associated with a decrease in blood lipid profile, blood pressure, glucose, and HbA1C level among diabetic patients.
But, it is important to note that a diabetic person should always consult their doctor before starting any kind of fasting.

Anti-inflammation effects

Dry fasting has some proven anti-inflammatory effects. Ramadan fasts are associated with significantly lower concentrations of inflammatory markers such as CRP, IL-6, and TNF-α.

CRP is a protein whose circulating concentrations rise in response to inflammation. High levels of CRP may be related to a higher risk of diabetes, hypertension, and cardiovascular disease.

IL-6 stimulates the inflammatory and auto-immune processes in many diseases such as diabetes, atherosclerosis, depression, Alzheimer’s Disease, prostate cancer, and rheumatoid arthritis.

TNF-α is a cell-signaling protein involved in systemic inflammation. Dysregulation of TNF production has been implicated in a variety of human diseases, including Alzheimer’s disease, cancer, major depression, psoriasis, and inflammatory bowel disease.

Lower blood pressure

Another great benefit of dry fasting is that it lowers blood pressure, a study says.
But it means that people with lower than normal blood pressure should consult their doctor before starting dry fasting.

Good for bones

A study showed that changes in dietary practices during Ramadan modulated PTH secretion to a pattern which might be beneficial to bone health.

PTH, also called parathormone, is a hormone secreted by the parathyroid glands that regulate the serum calcium through its effects on bone, kidney, and intestine.

Prevents coronary heart disease

Coronary heart disease (CHD), or coronary artery disease, develops when the coronary arteries become too narrow.

The coronary arteries are the blood vessels that supply oxygen and blood to the heart.
CHD tends to develop when cholesterol builds up on the artery walls, creating plaques. These plaques cause the arteries to narrow, reducing blood flow to the heart. A clot can sometimes obstruct the blood flow, causing serious health problems.

A study on 82 volunteers with a previous history of either coronary artery disease, metabolic syndrome, or cerebrovascular disease was conducted.
The results showed a significant improvement in 10 years coronary heart disease risk score and other cardiovascular risk factors such as lipids profile, systolic blood pressure, weight, BMI, and waist circumference.

dry fasting benefits

Dry Fasting And Autophagy

What Is Autophagy?

Autophagy is a cell renewal process when damaged cells or cell parts are removed and replaced, therefore creating a healthier and more functional cell.
Autophagy plays a housekeeping role and may clear damaged cell structures (such as mitochondria, endoplasmic reticulum, and peroxisomes) by removing damaged cell parts. Autophagy may also remove intracellular pathogens and is thought of as a survival mechanism.

Another popular way to explain autophagy is that when you stop eating and your digestive system isn’t loaded, your body has more “time and energy to mind the cell renewal business.”

How Does Autophagy Relate To Dry Fasting?

Autophagy can be induced by starvation, specifically by an increase of glucagon. When we eat, our insulin levels increase, and our glucagon levels decrease.

Conversely, when we don’t eat, or fast, our insulin levels go down, and our glucagon levels go up. This glucagon increase is known to be one of the most effective stimulators of autophagy.
Although there’s no scientific research that backs it, there’s a theory that dry fasting increases autophagy three times more compared to regular fasting.

As said before, the popular theory explaining how autophagy is related to fasting is that when the body isn’t loaded and busy digesting food, it invests the energy in self-repair.
When we drink water, our bodies are still busy with water-metabolism (absorption, urination, etc.).
So not consuming food nor any liquid, by theory, makes the autophagy increase.

Also read: Autophagy: The Cell Healing Process

Results of dry fasting

Dry fasting brings you the benefits of weight loss, improved cholesterol levels, anti-inflammatory effects, lowered blood pressure, and others, as mentioned above.

The fast weight loss might be what interests the most since each day of dry fasting can result in weight loss of 3 pounds. It means in 5 days of dry fasting you can lose up to 15 pounds. Most of which would be simply a loss of liquids, but the results still would be very visible.

Bodybuilders tend to avoid drinking water before competitions to make their muscles more visible and defined.

Thus, after breaking the dry fast, a big part of the lost weight comes back, meaning dry fasting isn’t the most sustainable method for weight loss.

Dry fasting dangers and safety cautions

After all the benefits are named, a fundamental question pops up “is dry fasting safe?“.

Every article on weight loss you see, every doctor or wellness expert you meet would tell you to always drink enough water.
That’s why dry fasting and improved health in the same sentence might sound really weird and counterintuitive.

This extreme diet approach really has its dangers. The number one danger is, of course – dehydration.

Three days without water can be deadly, although there are cases where people were able to survive up to 10 or even more days. Saying ‘barely survived’ probably would be more accurate.

It’s essential to note that drinking water and urinating is important as this way you discard the toxic chemicals your body makes during

Dry fasting can be extremely dangerous if:

  • You’re pregnant or breastfeeding.
  • You do it for prolonged periods (longer than 24 hours).
  • You’re on any medications (as water is needed for the medication to work and taking medications without water can be harmful to your kidneys and liver).
  • You’re doing any kind of (intermittent) fasting for the first time.
  • You’re exposed to heat.

Dry fasting stages

#1 Glycogen stage

Even if you’re not consuming any food or water, your body needs energy to run. After you’re out of blood sugar, your body starts using glycogen for energy. This is the first stage of dry fasting. This stage takes about a day, as glycogen stores last roughly 24 hours. It also depends on how physically active you are doing your dry fast.

Most claim this stage to be the hardest. It might be because using glycogen instead of fat for energy means producing less metabolic water, therefore, being more thirsty.

#2 Fat Burning stage

After your body uses all of the glycogen, it’s time to burn fat, the ultimate energy storage.
When the fat-burning state begins, dry fasters tend to feel less thirsty, as the body starts using metabolic water from burned fat cells.

A shortcut to this stage would be adapting yourself to a ketogenic diet before starting a dry fast.
When you enter ketosis, and your body is used to burn fat for fuel, the whole initially unpleasant dry fasting experience can become a little easier.

Dry Fasting vs. Water Fasting

Water fasting means abstaining from food or other drinks than water for certain periods of time.

The first obvious difference between these two is that during a dry fast you’re not consuming ANYTHING, including water. And that, of course, makes it way more extreme.

But, it might still be worth giving dry fasting a try because of the assumptions of 3X faster fat-burn and 3X increased autophagy mentioned before. Although that should be taken with a grain of salt, as there’s no valid scientific research to back this theory.

Saying which one is better is hard. Both of these fasting methods, especially if done for prolonged periods, are quite extreme.
Dry fasting can be more dangerous, but also says to have more health benefits. Interestingly, a lot of people claim that they feel less hungry on dry fast compared to water fast.

At the end of the day, it’s about you trying both of these for yourself and seeing what works the best.


A short disclaimer before digging in this part of the article – the experiences mentioned below should be looked at carefully, as what works for one might be harmful to another. If you’re considering going on a dry fast, especially a prolonged one, do thorough research first and take all safety cautions.

Science cannot explain it all yet. Dry fasting almost seems mysterious as it’s more enthusiasm than scientific research-backed.
A lot of dry fasting advocates also seem to have a mindset that’s criticizing massive consumption and the food industry altogether. Experienced fasters talk about psychological/soul/mind benefits rather than physical ones.

Let’s take a look at a few testimonials of dry fasters found around the internet and see how those who have actually tried it claim to feel:

Jennifer Owens

“I think dry fasting is superior to intermittent water fasting, as it is easier once you get used to it. My longest dry fast was 63 hours, but as soon as my lower back ached, I broke the fast. I then began doing one 24 hr dry fast per week and felt like I had plateaued.
I now do 23-hour Intermittent water fast with 16 hrs of it being a dry fast for five days a week. The dry fasting has defined my muscles, faded my wrinkles, and stretch marks. It takes a lot of mental strength going into the dry fast, so the almost daily feels more comfortable.
I started adding dry fasting into my regular intermittent water fasting six months ago, and the physical results are astounding – I look 15years younger, and my mental clarity and artistic ability have increased to levels I didn’t know existed in me.
I recommend dry fasting but not without gathering as much information as possible first.”

Barry Fennell

“I do not enjoy being electrolyte deficient at all. It’s a miserable experience. I was puking my brains out the other night from dehydration even after I had some electrolytes.”

Mitkovski Philosophy

“Changed my life as well. I’ve healed many things with dry fasting: old shoulder injury that never properly healed before and acne on my back.
But even better: depression, mood swings, lethargy. Improve my vision as well as teeth and oral health in general.
It’s the #1 way of healing yourself naturally.
The last one I did was three days of dry fasting right up until the evening of the New Years. Felt great and it just gets easier and easier the more you do it.
You develop new instincts. You start to love it more than food.”


“I passed out after not drinking for a few hours in Hawaii. There’s no way I’ll not drink water for a long time on purpose. So many people die every summer in my country from dehydration! (They forgot to drink, or forgot to bring water with them outside). Just don’t do it, it will be a very stupid way to die.”

Nigel Watt

“I love dry fasting waaaay more than water/snake juice fasting. The results are insane. Nothing like losing 10lbs in 2-3 days with absolutely no hunger!”


“I did a 72 hours dry fast. Was dizzy on day three, but kept pushing. I broke my fast, and the next day, I had a minor stroke. This was not my first time doing this. I had successfully done it before.”

We tried to pick testimonials representing both sides of the picture. Some of them are super positive; some of them just show how dangerous it can be.
Again, our advice to you, if you’re considering going on a dry fast, is to start slow and do as much research as possible.


Can you exercise while dry fasting?

Exercising during a dry fast might have severe consequences. You want to avoid water loss, so you don’t get dehydrated. If you’re on intermittent dry fasting, exercising might not be such a bad thing, but make sure to keep it easy.
An intense exercise without drinking water is just not a good idea.

How long can you fast without water?

Going without water for three days can be fatal.
Even if there are dry fasters claiming they abstained from water for up to 5 days and felt completely fine, that is not really recommended.
A beginner should start with no longer than 16-hour intermittent fasts and by no means exceed 24 hours.

Bottom line

With so many people swearing by its health benefits, it makes it at least curious to try.
Intermittent dry fasting, if safety cautions are taken, might bring outstanding health benefits.
Although prolonged dry fasts are something, one should carefully prepare for, as going without water for more than 24 hours can be extremely dangerous.

Should you try it? We have to leave that one up to you. Just remember to stay smart and cautious.