What Happens in Your Body During a “cleanse” or “detox”
Cleansing and detoxification is trendy, popular, and promises to flush harmful toxins out of your body and make you healthier. That’s a big promise, especially since they usually can’t point to any specific toxins they’re trying to rid you of.
Over the past few years, the term detox has shifted from a protocol designed to rid you of toxins, to often just a diet designed to temporarily reboot. It either promises fast weight loss or aims to get you used to healthy eating with residual effects that will last throughout the year.
The problem with this approach to diet, however, is that a diet designed to be temporary will always be too extreme to continue. For example, you can skip sugar altogether for ten days . This is not necessary, but some people find it a useful step towards reducing overall sugar intake.
Old-style cleansing takes it one step further. You often go hungry or eat only small amounts of certain foods or drinks (such as juice) on a schedule designed to be temporary and decisive.
What cleansers and detox products promise
For the most part, cleansing and detox are the same thing. They are usually used interchangeably and have the same basic goal: to remove “harmful” things from your body. They sometimes target a specific organ like the liver or colon, and supposedly detoxifying makes you feel better.
Both are often associated with limiting your compressed juice intake, avoiding certain foods, or consuming a juice mixture that supposedly rid your body of toxins. These alleged toxins are rarely described in detail by detergents, but are commonly referred to as “poisons” or “pollutants.” In the medical field, toxins can refer to everything from alcohol to food, drugs, and asbestos. “Detoxification” can also refer to drug addiction treatment, but that is a different matter — here we are specifically discussing cleansers with food and drinks.
There are too many cleanses and detox cleanses to delve into, but here are 10 that Shape magazine considered popular in 2014, perhaps the pinnacle of trendy cleansers. As an example, let’s take a closer look atMaster Cleanse , one of the oldest and most popular cleansers around. Here is an excerpt from the book that accurately describes how Master Cleanse works:
Cleansing begins with an herbal laxative tea in the morning and evening. If this is not enough to cleanse the intestines, he advises flushing with salt water. These stops are necessary for the elimination of toxins from the lemon juice cleanser.
Then I had to drink six to twelve glasses of lemonade, which consisted of lemon and maple syrup in the correct proportions, with a little cayenne pepper added to wash away the mucus that had been thinned out by the cleansing.
Sounds disgusting, right? Well, it might be worth it if you believe the promises made by Master Cleanse creator Stanley Burroughs:
For both beginners and advanced students, cleansing is the foundation for getting rid of all diseases. The purpose of this book is to simplify the causes and remedies for all disorders, regardless of name or title. By eliminating and correcting one disease, we correct them all, for each disease is treated with the same process of cleansing and promoting good health.
The hyperbole goes further, but you get the idea. Nutrition researcher Kamal Patel summarizes most cleansers as follows:
These diets have a dual purpose in common: weight loss plus the idea that toxins build up in our bodies that slow down our work and possibly kill us. Thus, a typical cleanse, say only with juices, is designed to move your intestines away from digestion and absorption towards “ridding the body of toxins.” This is where the benefits are claimed to lie, but in reality they could be elsewhere.
Most cleansers have similar promises, claiming that following some sort of juice fast (or other cleanse) can free your body of harmful toxins.
What happens to your body when you cleanse
We all know that fruits and vegetables are good for us, so following this logic, we might assume that a diet of only fruits and vegetables should be super healthy, right? Right??
Not really. If you drink nothing but juice for a week, you will lose weight, but that is because you are not eating, and not because your body “detoxifies.” Water is stored in your muscles along with glycogen . When you eat a low-calorie diet, you use up these glycogen stores and lose water weight with it. You will regain this water weight when you return to your normal diet. You also lack all the other vital nutrients like fat, fiber, and protein. In fact, some cleansers suggest that you avoid exercise when you do them because you are very low on calories, which leads to fatigue and dizziness .
After a few days, your body is mostly running on steam, and without protein, your body may instead start breaking down muscle tissue. Likewise, a lack of fiber in your diet tends to affect colon function, which may explain why people tend to describe their gut sensations when cleansing juices as similar to stomach flu .
Most importantly, a juice cleanse doesn’t do anything that your body isn’t already doing on its own. Dietitian Andy Bellatti reminds us that our body is already pretty good displays toxins. If they weren’t there, and you needed an annual detox, we would probably all be dead:
Will you end up in the hospital if you only drink juice for three or five days, or cause irreversible nutritional deficiencies? No, but you don’t need that either. Our body removes toxins on a daily basis thanks to the kidneys, lungs and liver. The whole point of going to the toilet is to flush out toxins!
While most of these cleansing and detoxifying treatments are harmless, they can cause some problems. Since juices don’t contain a lot of fiber, the body ends up absorbing more fructose, which we all know is not good for you in large amounts.
The good news about depriving yourself is that it takes months to become severely deficient in vitamins . Most of these cleanses are probably silly, but not seriously harmful if all you do is restrict food for a few days.
When it comes to claims of eliminating toxins, most commercial detox treatments do not state what a toxin is. And even when they do, they don’t prove they work. If they did, we could test the effectiveness of their claims. A 2009 Sense about Science study tested 15 commercial detox products and found that none could name toxins, agree on a definition of detox, or provide any evidence for their claims.
All of this suggests that the only thing a detox or juice cleanse actually does to your body is hunger and nutrient deficiencies for days.
Best alternatives to cleansers
So, cleansers don’t really do anything productive, and the special juice blend doesn’t flush toxins from your body. This does not mean that you cannot do other things to restore your health.
In fact, the idea of a cleanse is simply a reboot of your diet, as Bellatti agrees:
There is something to be said about the “food reset”. That is, to return to the basic principles of healthy eating (mainly whole, minimally processed, mostly plant-based foods) to re-habituate the taste buds to subtler flavors. However, this should not be confused with cleansing.
But he adds:
Nutrition and health are the big picture. What you do five or seven days a year is pretty inconsequential.
Instead of worrying about “detoxifying,” people are better off thinking about the daily intake of nutritious, healthy foods. Think leafy greens, beans, whole fruits, nuts, and seeds. The idea that six months of unhealthy eating can be corrected by drinking only green juice for 72 hours is misguided.
Likewise, some research suggests that real fasting, such as just drinking water, is beneficial. Patel explains:
Sometimes cleansing involves fasting or nearly complete fasting, and it can really be beneficial if you don’t have a medical condition or if you don’t do it for too long. There are many studies showing the effects of fasting on longevity; how fastingpromotes autophagy, reduces mitochondrial oxidative stress, an overall decline in aging-related signals, and the potential for preventing and treating chronic disease , at least at some level. Intermittent fasting can be a viable option for those who are otherwise looking for certain cleansing diets. You generally limit your food intake to a few hours a day (usually around 8). This is a simple and environmentally friendly way to eat without the need to purchase cleaning products.
Health and nutrition may sound confusing , but a healthy diet is all you need. No trick, no weekly cleansing, no detox. You will need a complete reboot of your diet .
This article was originally published in 2014 and was updated on 1/8/2020 with the latest information.