Need proof that 30 day fasts cause massive weight loss? Thinking this might work for you?
There’s a lot to consider. Fasting has great benefits but can be dangerous.
It’s best to begin with a story…
Before and After Pictures – 30 Day Water Fast Results
Since these pictures are privately owned by their respective blog owners, only the links are shared. You’ll notice a few interesting patterns:
- If you start at close to your BMI (or you look thin) you’ll look like an emaciated wreck when the fast is over.
- If you start overweight you end up looking great
The fasters in the posts below used different lengths for their fasts. Some were 30 days, some less.
- Check out Alex’s 30 day before and after pictures (link). Be warned, he looks pretty gaunt at the end.
- Sirita’s 30 day fast pictures (link)
- Scott Ragsdale’s 40 day fast pictures (link). Again, pretty gaunt.
Please pay heed to the fact that long fasts can be dangerous. See sections below about people who have died fasting. Some were trying to copy 40 day fasts similar to Jesus. Others have died after just 26 days.
Long day fasts are intriguing and are best done under medical supervision.
40 Day Water Fast Before and After Pictures
Want to see some before and after pictures of 40 day water fasts?
From the above list – Scott Ragsdale’s 40 day fast pictures (link).
Not a lot of blog posts on this and not surprising because it is incredibly dangerous!
There are a few youtube before and afters on the topic though:
Warning, this next one is a full documentary but it shows a 50 day water fast.
And one of my favorite bloggers, Steve Pavlina, tried a 40 day water fast.
21 Day Water Fast Before and After
For the curious, a few youtube videos of those that completed 21 day water fasts…
Average Weight Loss? How many pounds can you lose?
Fasters can expect to lose roughly one half to one pound of weight per day of fasting (1). Weightloss comes from a combination of burning fat and glycogen weight as well as water loss weight.
Strangely, many fasters say they don’t do it for weight loss. Maybe that’s true or maybe they’re trying to look more spiritual.
For the rest of us, we use fasting methods (e.g. 5:2, Warrior, 16:8) to lose weight as the primary goal.
What are the reasons to water fast?
Reasons are separate from benefits. There are a lot of reasons people conduct water fasts. The most common reasons include:
- Health – see benefits section
- Religious reasons – The most common religions in the world (e.g. Christianity, Islam, Hinduism, Buddhism, etc.) all involve fasting. Most of their founding leaders conducted long fasts. Followers of these religions seek to emulate what their founders experienced.
- Mental/Spiritual reasons – Many others have seen the mental health benefits of long fasts. Fasts are a time of reflection. You will face your inner demons. Expecting that and preparing for it will help you get more out of the fast.
What are the benefits?
- Weight Loss
- Fasting leads to more reduction in belly fat versus body fat (2)
- Reduced weight 3-9% (3)
- 4-8% reduction in body weight with alternate day calorie restriction (4)
- Subjects lost 2.5% of body weight and 4% fat mass on average after 21 days of alternate day fasting (5)
- 2.6% of body weight lost over 12 weeks (6)
- Body weight reduction of 2.5 kg and belly fat reduction of 0.7 kg (7)
- Water fasting reduced weight beyond the initial fasting period (8)
- Increased fat burning
- Increased metabolism
- Increase growth hormone (to preserve muscle mass during fasts) (19, 20, 21, 22, 23, 24, 25)
- Delay Aging, Live Longer (26, 27, 28, 29)
- Lower insulin levels (30, 31, 32, 33)
- Reversal of Type 2 Diabetes (34)
- Decreases chronic inflammation (38, 39)
- Lower blood cholesterol (40, 41, 42, 43)
- Improves brain function (44, 45, 46, 47, 48)
- Increases autophagy (removal of dead cells and proteins) (49, 50)
- Reduces your appetite, leptin response, and cravings (51, 52)
- Reduces Cancer Risk (53, 54, 55)
- Retains muscle mass
Can I speed up my metabolism after a 30-day water fast?
Yes, eat more. Dr. Jason Fung goes into depth on the many studies relating calorie restriction and overeating and how they affect metabolism. It’s a big part of what he discusses in The Obesity Code.
In short, restricting your calories for long periods will lower your metabolism (58), even years after the study (59). Increasing your calories for long periods will increase your metabolism. A study by Ethan Sims on Vermont prisoners that were asked to eat 10,000 calories a day found that they did increase weight and body fat but not as much as was expected due to the increase in metabolism (60).
The type of calories mattered. One self-experimenter, Sam Feltham, ate a low carb/high fat diet of 5,000 calories per day and ended up losing 1” off his waist and only gained 3 pounds after 21 days (61). When he repeated that study using the Standard American Diet high is high in fat, carbs, and protein he found the calorie increase matched his expected weight gain (3000 calories extra = 1 pound of fat) (62).
Long term fasting will fall into the first camp – long periods of low calories will reduce your metabolism. This is natural. Your body does this to keep you alive.
Intermittent fasting, on the other hand, breaks the cyle. By quickly going back and forth between no calorie and normal calorie days you get the weight loss benefits of fasting while maintaining a normal metabolism (63). In fact, 24 hour fasts have been shown to increase metabolism (64). This is likely the reason so many short-term fasters rave about increased energy and clarity during their fasts.
Is it safe?
Fasting can be safe (65). You were designed for it as part of human evolution. However, you may have conditions that make it unsafe.
You should always consult with a doctor before starting fasting. The final decision on safety should be up to them.
What to Expect (Days 1 through 2-3) – The Hunger Gate
The first few days are the most difficult. Let’s call it the hunger gate. Your body has plenty of glycogen stored to get you through the first 12 – 16 hours. Still, you will experience intense hunger.
Pay attention though and you’ll notice it’s during meal times.
This isn’t true hunger. It’s psychological hunger.
Your mind expects to eat at certain times of day. When those times come it rings the internal dinner bell and you get hungry.
It’s the same as Pavlov’s dogs salivating when they heard a bell. They were trained to expect food right after the bell sound. It wasn’t hunger. It’s just habit.
What to Expect (Days 3 – 9) – Maximum Fat Burn
Days 3 through 9 is when fat burning goes into high gear. Your body has depleted it’s glycogen and stored carb reserves so it turns to fat. Muscle is preserved and fat becomes the fuel of choice.
This is the time fasters report greater energy levels. It’s because your body is now optimized to burn fat.
Also, hunger typically isn’t as bad in this phase. Your body is getting everything it needs from your fat stores. There’s no need for it to send extreme hunger signals.
You will feel true hunger at this stage though. They type of hunger felt in the throat like thirst. This is different from psychological hunger built on daily eating habits.
Even getting to this stage is a huge accomplishment. Few learn the difference between true hunger of the body gently calling for food versus ravenous hunger of the mind needing it’s fix.
What to Expect (Days 9 – 30) – Beware the Boredom
Boredom. Fasters love to talk about the energy and the fasting high. A few also honestly discuss the boredom that occurs.
You’re not going out with friends to eat. You’re not cooking. You’ve never known so much free time.
This is the last stage of the fast and it comes with dealing with emotions and thoughts.
It’s why Buddha, Jesus, and religious practitioners have used longer fasts.
You are forced to deal with emotions and thoughts you’ve been avoiding.
No longer hidden by food, friends, drink, and distractions. Now they get full attention.
They’ve been waiting.
If you read accounts of people going through extending meditation retreats the same thing occurs (66).
By the end of the first week, after their meditation high, they get restless. Some never get over the boredom and restlessness (67, 68)
They feel like leaving. They often do.
Being at a guided fasting or meditation retreat helps. You have social pressure of the other attendees. They stay so subtly you feel the need to stay.
A lot of doctors and fasters talk about all the physical cleansing happening to your body during a fast. It cleans out damaged cells and proteins. You burn fat which also stores fat soluble chemicals, washing them out. You reset your insulin response.
A few also talk about the emotional cleansing that happens.
If you have any interest in a longer day fast you should prepare for this.
At minimum you will deal with intense boredom. If you are usually a busy person take advantage of this.
It’s a time to clean house, not just physically but mentally. Which also includes spiritually.
While you can do this alone, it’s better to have a guide. Do this with others that can help you through it. Both physically via physicians and mentally via psychologists or meditation retreat leaders.
That’s why we recommend you do this under supervision. It’s safer, easier, and you’ll likely get a lot more out of it.
How to break the fast?
There are many ways to break a fast. For longer fasts you always want to break it with light foods. Ghandi would break his fasts with orange juice. I break my fasts with a prepped meal that’s easy to digest (e.g. fruit) and low in calories.
What you don’t want to do is go to a buffet or gorge on food. You’re stomach won’t be able to handle it.
Try these fast-breaking foods instead:
- Orange juice
- Apple juice
- Honey dew melon
- Low salt vegetable juice (preferably fresh squeezed)
- Vegetable broth
- Cooked carrots
- Plain rice, well cooked (super soft)
- Vegetable soup
Avoid raw vegetables or meat products. For vegetables, it’s easy on your stomach if they are cooked and super soft. Meat or even high protein vegan meals will raise the acid levels in your stomach which could upset you. Save meat or high protein vegetarian meals for later.
How long should you water fast?
This is a question you should discuss with your primary care physician. If you have never fasted before you should not attempt a long fast.
Just like with working out, you have to build up slowly to heavier weights. With fasting, start with short fasts where you skip breakfast and lunch. Build yourself up to a full day fast.
Doing these fasting prep exercises will make it much easier when you attempt a longer fast.
The length of a water fast also depends on your starting body weight. The longest fast ever conducted last 382 days (69). The man that did it started at 456 pounds. He lived off of body fat until he reached 180 Lbs. He stayed at 196 pounds even five years later.
Others have attempted water fasts and died after 26 days (70). Some have died days after an extended fast (71).
Choosing the length of your fast is crucial. Ask your doctor. Do not choose it alone.
As Dr. Jason Fung, author of The Obesity Code, said that you should feel well while fasting. If you feel tired or bad then stop. (72)
What are the challenges and how to deal with them?
- Some have died (73, 74)
- Cold arms and legs – You could experience cold extremities while fasting. Tips here are location dependent. If you’re in a hot climate this won’t matter as much. For temperate or cold climates make sure you have access to a light jacket at work or hat.
- Irritability – This is one of my bigger challenges with longer fasts. I get irritable quickly. For me it’s aggravated by caffeine. To lessen irritability, cut back on the coffee and caffeinated beverages while fasting.
- Hunger waves – Prepare for waves of hunger. Contrary to what you expect, you won’t get ravenously hungry for the entire day. Instead, hunger comes in waves during fasts. These waves align with your normal eating times. The best way to deal with them is to stay busy. See the tips on handling boredom during fasts in this article as well.
- Loss of electrolytes – For longer water fasts you run the risk of depleting yourself of electrolytes. What are electrolytes? The salts and minerals needed in small amounts to run your body (e.g. sodium-potassium pump). You normally replenish these by eating. During a water fast you’ll want to drink vegetable broth or similar salty, no calorie drinks.
- Boredom – Boredom, like hunger, is to be expected on longer fasts. You will have more time and energy than expected. If you’re not busy enough this will transform into boredom. To deal with it see the tips on boredom.
- Insomnia – Mentioned below, insomnia is another challenge that can happen when fasting. Some people have trouble sleeping if they haven’t eaten. See the section on insominia tips in this article for more.
- Eating too much after the fast – I’ve been guilty of this more times than I like. I finish a big fast then immediately go to a buffet. Doing so has destroyed my stomach even on shorter fasts. One of the benefits of fasting is shrinking your stomach and reseting your appetite so you don’t need as much food to feel full. Eat a big meal after a fast and you stretch out your stomach and remove this benefit. Instead of pigging out after a fast, prep a small filling meal in advance. It could be having a set meal at Chipotle or prepping your own meal at home. For longer fasts see the section in this article on how to break a fast. The main tip is to avoid stressing out your stomach and eating super light but filling. Think watery fruits.
- Headaches – This is another common downside some fasters experience. Caffeinated beverages and aspirin or similar medication can help. Be sure to drink lots of water. Headaches are a common symptom when you fast from coffee. While coffee is allowed on fasts you might want to take this opportunity to break a coffee addiction as well.
How to deal with boredom
Expect boredom on your fasts. Even when I just fast for a day I get bored at some point. You have so much more time and more mental energy on a fast. You don’t have to decide what to eat. You don’t have to cook it. You will be rich in time and thoughts.
Those thoughts will try to sabotage you. Expect to get restless and bored. Sit with it.
Here’s ten ways to deal with boredom on a fast:
- Journal – This helps give you something to do plus you just might work out a few long, standing issues. I’ve used isolated fasts to deal with big turning points in my life in the past. It’s a great time to reflect.
- Go for a long walk or easy hike
- Call up a friend
- Stay busy at work
- Go see an independent film, something thought provoking. Bring a friend and talk about it afterwards.
- Go to a cafe for a coffee
- Read a book
- Watch your favorite show – Don’t try and be perfect. You’re goal is to complete the fast. Sometimes distraction is needed.
- Go to a board game cafe
How to deal with insomnia
Insomnia happens on fasts. Especially with long fasts you should expect it. The easiest way to deal with it is let it happen. Then on the next day take a nap.
If you come home late from work, just set a time for 30 minutes and take a power nap. Try not to nap longer than 30 minutes. You’ll likely trigger another night of insomnia.
If insomnia will affect your job then account for that when deciding on doing a longer fast. It may not be the best fit for your lifestyle. You can get a lot of the benefits of fasting by short, intermittent fasts instead.
Avoid medications. Again, if you are on medication you should discuss this with your doctor before starting a fast. You should not need sleep medications while fasting.
Cleaning out your body is part of the experience.
Insomnia is a great opportunity to take some alone time to do the following:
- Read books
- Sit outside and think
- Go for a night walk
Tips and Pointers
- Consult a doctor before starting a 30 day fast. There are many that support fasting for health.
- Read the case studies of others so you know what to expect.
- Stay busy the first 3 days. Hunger and mental anxiety are highest at that point.
- Drink lots of water and electrolytes (75). You need electrolytes (i.e. salts) to function. The sodium/potassium pump is what your body uses to move electrical signals through your nuerons and to transport ions across cell membranes (76). Food is your normal source of electrolytes. Drink too much water without food and you can get water poisoning, also known as water intoxication (77). To prevent this, drink low or zero calorie electrolyte drinks such as vegetable broth.
Note: If you click some of the links in this article we may earn a small commission at no additional cost to you.
Best Youtube videos on water fasting
- How much weight did I lose after a month of fasting? – 30 day fast results https://www.youtube.com/watch?v=u_MKZ8zqlC0
- Dr. Alan Goldhamer: Safe 40-Day Water Fasts And The Traits Vital People Share https://www.youtube.com/watch?v=_grRFH5oRDQ
- Dr. Berg – dangers of fasting longer than 24 hours – https://www.youtube.com/watch?v=xwTGZ27LNFQ
- 25 DAY WATER FAST RESULTS | I lost 30 POUNDS in 25 DAYS VLOG https://www.youtube.com/watch?v=pIOqtwksnlQ
- 30 Day Water Fast (beyond weight loss) https://www.youtube.com/watch?v=PU3FX5_d3TA
- 31 Day Water Fast! (INSANE RESULTS) https://www.youtube.com/watch?v=dbeX-PTaEFM
- NO FOOD 28 DAYS – 6 Months Later :( https://www.youtube.com/watch?v=nfNRetld7nQ
- 30 Day Water Fast Weight Loss Results https://www.youtube.com/watch?v=2JoBKbxKNqU
- Dr. Berg – How to do Intermittent Fasting for Serious Weight Loss https://www.youtube.com/watch?v=lwCRjwDs1Ek
- Dr Fung – Intermittent Fasting for Weight Loss w/ Jason Fung, MD https://www.youtube.com/watch?v=v9Aw0P7GjHE
- Dr. Fung – Dr. Jason Fung – Therapeutic Fasting – Solving the Two-Compartment Problem https://www.youtube.com/watch?v=tIuj-oMN-Fk
- Cancer Disappears With Water Fasting -Dr Alan Goldhamer https://www.youtube.com/watch?v=fSH4vBBSDmg
Doctors that can guide you through this
Before you start a long term fast you should always consult with your primary care physician.
If you want to work with a doctor that has experience in fasting seek someone local first. Simply google “Doctor Fasting [name of your city]”. For Denver I found a few doctors with “fasting” in their description no the first page. Depending on the size of your city this may take some time.
You can also connect to doctors through the retreat centers mentioned elsewhere in this article.
Doctors that have fasting centers or programs:
- Dr. Jason Fung, Author of The Obesity Code and Co-Author of The Complete Guide to Fasting, The IDM Program
- Dr. Fuhrman, Author of Fasting and Eating for Health, The Wellness Center
Fasting retreat centers
Fasting retreat centers are a great option for longer term fasts. You get medical supervision combined with a community of others helping you safely complete the fast. Whether you fast for religious reasons or health reasons, you can find the right clinic for you.
- Dr. Jason Fung, Author of The Obesity Code and Co-Author of The Complete Guide to Fasting, The IDM Program
- Dr. Fuhrman, Author of Fasting and Eating for Health, The Wellness Center