The 3 Day Water Fast: A Complete Guide [How To + What To Expect] (2023)

Approaches to eating and dieting span the gamut from strict weight loss diets like the Whole30 diet, which dictates what you can and can’t eat, or the keto diet, which essentially eliminates an entire macronutrient from the diet to more permissive diets that involve altering the way you structure you’re eating but don’t specify exactly what you can and cannot eat.

Examples of the latter include the CICO diet (calories in, calories out), carb cycling, and intermittent fasting.

Another more extreme approach to dieting is water fasting.An occasional 3 day water fast is a fairly common practice meant to help facilitate weight loss and support other health-related goals.

Water fasting for three days can sound completely overwhelming, if not impossible if you have never done it before. However, proponents of 3 day water fasts attest that with a little preparation and mental grit, it’s not only worth it but not that hard to do once you actually try.

In this 3 day water fast guide, we will discuss how to do a 3 day water fast and the benefits of a 72 water fast.

We will cover:

• What Is a 3 Day Water Fast?

• Is 3 Day Water Fasting Safe?

• How To Do A 3 Day Water Fast

• What to Expect With a 3 Day Water Fast: Benefits of Fasting

Let’s dive in!

What Is a 3 Day Water Fast?

A 3-day water fast, also called a 72 hour fast, is an extreme version of water fasting that involves consuming only water for 72 hours or 3 full days.

As the name suggests, water fasting entails consuming only water for the entire duration of the fasting protocol.

With that said, some people who practice water fasting permit non-caloric beverages like green tea, herbal tea, club soda, or very low-calorie beverages such as black coffee during the fast.

It is also common to supplement water with unsweetened electrolyte powders, tablets, or capsules during a 3 day water fast, although strict protocols only allow you to lick pure pink Himalayan salt to attain necessary sodium.

Is 3 Day Water Fasting Safe?

A 24 hour water fast, or water fasting for a day or two, is not particularly uncommon, but a 72 hour fast is fairly extreme and should only be done under the guidance and supervision of a medical professional.

Although studies suggest that prolonged fasting can be safe, water fasting for three days is often not recommended nor safe for some people, and there are usually healthier, less severe alternatives for weight management and perceived health benefits.

These may include a shorter fast, an intermittent fasting diet, a well-balanced program of diet and exercise, etc.

It’s highly recommended that you speak with your healthcare provider before embarking on a 3 day fast and discuss potential safer alternatives.

Fasting for 72 hours may result in adverse health and metabolic changes such as dehydration, a loss of lean muscle mass, hyperuricemia, hyponatremia, protein sparing, sodium and potassium sparing, decreased serum calcium and magnesium levels, and acidic urine.

Additionally, a 72 hour fast can lead to symptoms such as headaches, nausea, vomiting, constipation, the inability to regulate body temperature, muscle loss, lightheadedness, shakiness, poor healing, blurry vision, difficulty sleeping, mood instability, and adverse nutritional deficiencies.

How To Do A 3 Day Water Fast

If you’ve never tried water fasting before, you’re probably wondering, “How do you do a 3 day water fast?”

This question seems simple enough, but it can actually be trying to pinpoint the answer to two distinct questions:

• How do you do a 3 day water fast from a practical perspective? (i.e., what does water fasting entail, what can you eat, what do you have to do to prepare, etc.); and

• How do you fast for 72 hours from a mental/hunger/discipline standpoint?

Let’s address both of these valid questions.

After you get the go-ahead from your healthcare provider, the next steps are to physically prepare your body and mentally and emotionally prepare your mind to fast for 72 hours.

To physically prepare yourself for a 3 day water fast, it is advisable that you practice with shorter fasting intervals before you take on a full 72 hour fast.

Although this isn’t required, it can help your body get used to the physical sensations of not receiving any type of energy intake for an extended period of time.

For example, you might try a 24-hour fast one week before your 72 hour water fast, or you might try several days of 18/6 intermittent fasting (extending your overnight fast for a full 18 hours and then only allowing the consumption of food during a 6-hour window during the day) or a 20/4 intermittent fasting diet for a week.

If your body is not accustomed to any type of fasting or intermittent caloric restriction, it can be quite jarring to suddenly have a complete absence of calories coming in.

Engaging in “mini” fasts will improve your ability to burn fat and use ketones for energy (which will occur after prolonged fasting), which can make your longer water fast more comfortable.

Whether or not you decide to try shorter fasts to prepare your body, it’s a good idea to be deliberate in your food and beverage choices in the 48 to 72 hours before you begin your water fast.

Eliminate alcohol, soda, excessive caffeine, and processed foods high in sugar, salt, hydrogenated oils, and artificial sweeteners, as these can trigger appetite.

Instead, focus on eating nourishing, unprocessed foods such as vegetables, fruits, whole grains, lean proteins, nuts, seeds, eggs, and fermented foods like yogurt, kefir, sauerkraut, kimchi, and tempeh.

It’s also wise to resist the urge to “stock up“ or overeat with a big meal heading into a 72 hour water fast. Binging can throw your insulin and blood sugar levels into haywire and can also compromise some of the potential health and weight loss benefits of water fasting that you’re ultimately aiming for.

Once the 3 day water fast begins, you will drink only water (and potentially herbal tea or black coffee if you choose) for a full 72 hours.

You cannot eat any caloric food or beverages, and most people avoid all artificial sweeteners as well.

In terms of the second question about how to mentally do a 3 day water fast and control your cravings and manage your hunger, it helps to come up with a few strategies you can employ when things get tough.

There’s no “secret” or magic solution that will make fasting for 72 hours feel easy.

However, some people find things like mindfulness meditation, journaling, praying, taking walks, doing some kind of art, playing golf, listening to audiobooks and podcasts, or doing needle crafts can be a good way to ground themselves when they feel overwhelmed with cravings.

It’s important to state that if you experience any type of concerning symptoms, you should consult your doctor immediately.

What to Expect With a 3 Day Water Fast: Benefits of Fasting

There are a variety of different benefits that can potentially be enjoyed by occasionally doing prolonged fasts or engaging in intermittent fasting with more regularity.

Some of the reported benefits of fasting include the following:

• Supporting weight loss and a reduction in body fat percentage because you are creating a caloric deficit.

• Reducing oxidative stress and inflammation.

• Improving blood sugar regulation and reducing insulin levels. For example, studies investigating the effects of intermittent fasting on blood sugar and insulin levels in people with pre-diabetes have found that intermittent fasting can reduce fasting blood sugar by 3-6% and fasting insulin levels by 20-31%.

• Reducing LDL (“bad”) cholesterol and triglycerides.

• Promoting autophagy and improving cellular health.

• Reducing the risk of heart failure by as much as 70%.

• Increasing the secretion of human growth hormone (HGH).

• Reducing the risk of various diseases, including cancer and neurodegenerative diseases.

While this list of benefits of fasting is impressive, many of these benefits are achievable with more conservative approaches to fasting, such as intermittent fasting diets and periodic 24-hour water fasts.

You might not need to do a full 3 day water fast to achieve the results you are looking for, so it often makes sense to review your options with your healthcare provider.

With that said, some people who do occasional 3 day water fasting find that it’s a powerful physical and mental reset that helps them feel much more vibrant, focused, and healthy afterward.

The response to prolonged fasting is quite individual, so work with a healthcare provider you trust, and try to be open to experimenting to find what works best for you.

To get started with a 24-hour water fast, check out our guide here.