One of the newest, fastest, but arguably the most dangerous, weight-loss fads that hit the market this decade. We say new, but water fasts have actually been around for thousands of years, although most of these were for religious purposes –it’s only recently, however, that people started using water fasts for weight loss. Results, of course, have been varied: while everyone who goes through a water fast will lose weight, it comes with a slew of side effects, both good and bad, that should make most people rethink how they approach water fasts, or if they should approach it at all.
In general, fasting will help you lose weight; any diet that restricts your calorie intake will do that. Water fasts are exactly what it sounds like: all kinds of food are forbidden, except for water. This might sound dangerous, but remember that the human body can go three weeks without food, but it wouldn’t last 7 days without water, depending on the weather (this number goes down drastically in places with dry heat). But even before you hit that mark, kidney damage will set in long before you start dying of dehydration.
Scary stuff, but do water fasts actually work?
What Exactly are Water Fasts?
Just as the name implies, water fasts are a type of fast that excludes all kinds of food, whether solid or liquid, during its duration, with water being the only exemption (sorry, smoothies count as food). The Juice Cleanse, which is essentially a water fast but with the addition of lemon juice and maple syrup, is modeled after the water fast but isn’t counted as a water fast due to the addition of the juice and the syrup.
There are 3 main types of water fasts: 24-hour water fast, 36-hour water fast, 72-hour water fast, and a 5-day water fast, all of which vary in weight loss results and health effects. Of course, the longer the fast, the more closely a medical professional should be supervising. In fact, even 24-hour water fast should be done with the blessing of a doctor or a nutritionist. Yes, Josh Peck’s weight loss is impressive (and involved fasts, too!), but he did it safely and with medical professionals monitoring his every move.
Let us reiterate: DO NOT START ON A WATER FAST WITHOUT FIRST CONSULTING YOUR DOCTOR. Water fasts, while effective at weight loss, can cause a number of negative effects on the body, some of which can be irreversible.
How Do Water Fasts Work?
Studies on the water fast are few and far in between, which means there’s no clear guideline (at least, from a medical perspective) on how to start and how long to go for. Again, water fasting for weight loss results in a drastic reduction in weight but with certain consequences. Again, and we hate to sound like a broken record, but always consult with medical professionals before, during, and after a water fast.
(That being said, there are people out there who categorically should NOT try a water fast, including, but not limited to: children, pregnant women, people with eating disorders, people suffering from gout, and both types of diabetics. Attempting a water fast with these groups of people is dangerous, if not life-threatening. In fact, even taking ‘fat-burning’ medications, like Phen375, can have potentially dangerous side effects)
In general, most people start their water fast by preparing their body at least a week in advance: this usually involves a gradual, but drastic, cut-down on their calorie intake. Because each person’s body chemistry, it’s hard to decide on a single, calorie intake plan. Normally though, adult males are generally recommended to consume about 2,500 calories a day, while adult women are generally recommended to take in 2,000.
A good way to start a water fast is to start cutting your calorie intake by half every day for a week (or, in some cases, 3-4 days) before you start a water fast. This will help your body become acclimated to the lack of calories your body will be taking in for the duration of your fast, ideally lessening the severity of certain symptoms (i.e. hunger pangs, dizziness, etc.).
Once your water fast starts, any and all foods or liquids that have calories are now excluded from your diet; the only thing that should be entering your body is 2-3 liters of water every day.
24 Hour Water Fast
During a 24-hour water fast, weight loss results might not be observed immediately; most of the weight you’ll be losing at this time will be, ironically enough, water weight, most of which will be replaced by the water you’ll be drinking. Still, a 24-hour water fast is popular with many people who are looking to do a quick ‘cleanse’. This is probably the safest fast between the other water fasts, as its short duration allows you to avoid many of the negative consequences of a prolonged water fast, not to mention help you reset your calorie intake.
36 Hour Water Fast
For people looking to lose weight, a 36-hour water fast will have the most notable effect. That’s because, after 36 hours of fasting, your body will start burning off excess fat for energy, to make up for the lack of calories (usually in the form of carbohydrates) that you usually intake. Take note, however, that 36-hour water fasts are usually where negative effects start to happen, e.g. dizziness, nausea, extremely low energy levels, etc. Beyond this amount of time, it’s best not to operate heavy machinery.
5 Day Water Fast
After 5 days of consuming nothing but water, your body will start producing ketones. When your body doesn’t have enough sugar or glucose to turn into energy, your liver starts converting your fat into a type of acid called ketones, which is then used to fuel you throughout the day. This means that your body enters a state known as Ketosis, where it actively breaks down your stored fats as an energy source.
5-day water fasting results in drastic weight loss, but it’s also where some of the most severe side effects of starvation take place, with the most commonly reported problem being Lactic Acidosis and Electrolyte Homeostasis Breakdown, a condition where your body’s homeostasis (that is, the chemical balance that maintains proper bodily functions) is thrown out of order due to the lack of electrolytes. Do not attempt this without strict medical supervision, and it’s best to stop here (although some people push the water fast to 6, even 7 days, but this is dangerous and definitely not advised).
After Water Fasting
Once your fast is done, it’s time for your body to start recovering and start normalizing. However, just because you haven’t eaten in 5 days doesn’t mean you gorge yourself in your next meal; in fact, eating a heavy meal after a water fast is not recommended at all.
The phase after a fast is usually just as important as the fast itself: this is a time when your body will continue to break down fats and readjust its metabolic rate. Eating a large meal or taking in excessive amounts of calories can mess with this and even undo all of your hard work.
Even worse, a condition known as Refeeding Syndrome can set in, a potentially fatal issue that happens when your body is suddenly inundated with nutrients after starvation. Because your body has adapted to a zero-calorie diet, the reintroduction of food could shock it, leading to severe cardiac, pulmonary, and even neurological damage.
The safest way to exit a water fast is to reintroduce foods slowly over a period of time, much like how you prepped for the fast in the first place, only this time by adding food. Most people break their fast with a fruit smoothie the day after their fast ends. This is followed by 2-3 days of slowly upping calorie intake to their desired level (usually below the RDA).
Remember, and we cannot stress this enough, always consult with a medical professional before, during, and after your water fast.