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It seems like a lot of celebrities are promoting detox diets.  Do they work?  Which ones are the safest and most effective? – M.H. Queens, NY.

Great question!  These are all over the internet.  Before we get into the diets and supplements themselves, let’s talk about “toxins” and how your body gets rid of them. Click here for a basic explanation of what a toxin is.

What toxins are these diets and supplements targeting? Many health blogs will classify toxins as “endotoxins”, which they say are waste products made in your body, and “exotoxins”, which they define as toxins that make their way into your body in your food you eat, the water you drink, or the air you breathe.   In the parlance of science, both of these definitions are wrong – an endotoxin is a very specific and dangerous toxin produced by gram-negative bacteria, and an exotoxin is a toxin released by bacteria, often as a defense mechanism.  The proper terms for each are metabolic waste products and xenobiotics, respectively. A xenobiotic is something that is foreign to the body, though it may or not be toxic.

Note: This isn’t just an exercise in vocabulary – scientists use very specific words with very specific meanings so that everyone knows what everyone else is talking about. This is important because if you google the wrong words, you won’t get the answer you are looking for when you try to research these things yourself.  Anyway, on with the show!

Let’s start with metabolic waste products, which are the leftovers from your body turning food and oxygen into fuel. The main waste products your body produces are carbon dioxide and urea (as you may know them: exhaled breath and pee), though there are many other molecules your body disposes of regularly. Metabolic waste is removed mainly by your kidneys (urea and all other nitrogenous waste), lungs (carbon dioxide and other gases), and feces via bile (bilirubin, the breakdown product of hemoglobin). Another metabolic waste product that you will often hear about is lactic acid. Lactic acid builds up in your muscles during strenuous activity when the oxygen demand is insufficient to meet the muscles needs. However, lactic acid is not eliminated form the body – it is simply recycled back to glucose (sugar) after the strenuous activity is over.

A xenobiotic, on the other hand, is anything in your body that really isn’t supposed to be there. People often think of these as man-made chemicals, but that is not necessarily the case – many common fruits and vegetables have low levels of chemicals that serve no purpose in our bodies and must be eliminated as well. In terms of health risk, the ones we are most worried about include metals (such as lead, mercury, and arsenic), and environmental and food contaminants such as pesticides, dioxin, and PCBs (flame retardants). You will also hear some people talk about “chemicals from foods” in general terms, but intentional food additives – things like artificial sweeteners or flavors, high fructose corn syrup, etc, are safe (when eaten in moderation) and do not accumulate in your body, so you don’t need to “cleanse” yourself of these.  The same goes for GMO foods, since the products of the added genes are proteins, which are broken down to simple amino acids in your stomach.

Speaking of cleansing, another common target of these detox diets and supplements is the colon.  Your GI tract is indeed an important avenue from removing waste products and xenobiotics from your body. However, your colon is very good at doing it’s job, and it doesn’t generally need help.  When it does, you’ll know it – it’s called constipation, and it means you need more fiber in your diet.  Fiber supplements are a mainstay of detoxification treatment, but they don’t increase the quantity of toxins you excrete – all it does is get the process moving faster. With that said, eating a high fiber diet is definitely healthy. If you don’t get enough dietary fiber, the use of fiber supplements is also beneficial, even if they don’t detoxify your body per se. Some people will even go so far as to perform enema colon cleanses. These do not detoxify you, because everything you cleanse out was on it’s way out anyway.  They can also be dangerous. Skip the colon cleanse.

So how do you help your body get rid of toxins? If you are a normal, healthy adult, it turns out there isn’t much you can do.  Metabolic waste products are excreted as they are produced, and while some may claim their specific diet or supplement will increase the elimination of these compounds, this is not supported by science.  If you were acutely poisoned by something, there are treatments – specifically activated charcoal, which can pull toxins out of your GI tract, or chelation therapy, which can remove heavy metals.  However, these treatments should only be performed by doctors.  Unfortunately, if someone tells you their diet or supplement will “pull”, “wash”, “cleanse”, “scrub” (or similar) the toxins form your body, they are lying to you.  Human physiology just doesn’t work this way.

There is one way to remove certain toxins quickly form your body with diet, and that is rapid weight loss.  There are several reports showing that rapid weight loss releases stored up fat-soluble toxins from your fat cells into your blood.  This may sound dangerous in theory, but there are no confirmed cases of these released toxins causing health problems.  You would need to loose a lot of weight (and have a lot of fat-soluble toxins in your body) for this to be a problem.  Any risk is also counteracted by the weight loss itself – since we know that loosing weight is one of the best possible things you can do for your health.

There are an awful lot of detox diets and supplements out there.  Many are endorsed by celebrities like Gwyneth Paltrow, Dr Oz, or one of the Kardashians.  Do not take nutritional advice from these people.  While it would be impossible to review all of the detox options in a single post, here are some of the more common ones:

• Cleansing or detoxifying supplements using herbs.  Herbs don’t magically bind toxins and escort them out of your body.  Sorry…
• Detox enzymes (from food or supplements). Do you know what happens when you eat and enzyme?  It gets digested down to amino acids, meaning that is is no longer an enzyme seconds after you eat it.  It’s just a source of protein at that point, and it can’t help you eliminate toxins.
• Glutathione and N-acetyl-cysteine (NAC).  These common supplements are grounded in science.  Glutathione is indeed one of the most important anti-oxidant and detoxifying molecules in your body.  Unfortunately, when you eat gluathione, it is quickly digested and therefore useless to you.  NAC is a precursor to glutathione, and there is some data suggesting that it could help boost glutathione levels in animals and maybe even people.  However, for a normal adult with normal levels of glutathione, there is no data to suggest that taking NAC will increase your glutathione levels above normal or speed up it’s work detoxifying toxins in your body.
• Anti-oxidants.  These are good for you!  While they don’t “cleanse” or “wash” toxins form your body, they do help detoxify them.  You probably have plenty of antioxidants in your body for the job already, but taking more within reason won’t hurt.
• Selenium.  This is often suggested because it is required for the proper functioning of some critical detoxification enzymes.  It may also bind mercury in your gut, but you probably don’t have much mercury in your gut anyway.  Again, it’s good to get selenium in your diet, but more is not better – selenium is toxic at high levels.
• Activated charcoal.  As mentioned above, this is very good at removing toxins form your GI tract if you’ve eaten something you shouldn’t have. Unfortunately, it will not pull toxins out of your body after they have been absorbed into your bloodstream, so you’re only cleansing the food you are currently digesting and nothing more. Another problem with activated charcoal is that is binds to a lot of things – including vitamins, minerals, medications you are taking, and even the other detox supplements you just took, potentially rendering them all useless.  Stay away form this one unless otherwise direct by a doctor.
• Chelation therapy. Chelation therapy uses compounds called “chelating agents” to bind to metals and help remove them from the blood stream. This can be a lifesaver if you have been poisoned by heavy metals such as mercury, cadmium, or chromium. However, chelating agents are big molecules, and are not absorbed when given orally.  Effective chelation therapy requires intravenous administration of chelating agents under the supervision of a doctor.  If someone is trying to sell you an oral supplement as chelation therapy, it won’t work.

So why do so many people swear by detox diets in particular?  There is actually a very good scientific reason for this.  Detox diets are generally very healthy!  Most advocate raw food, high in fresh fruits, vegetables, and fiber, while avoiding high sugar or fatty foods. Most diets also cut out drinking alcohol and smoking, which are the sources of the most damaging toxins in our society, hands down. Perhaps just as important as the quality of the food is the quantity of food: detox diets are often very low calorie (some recommend fasting, don’t do this). If you add in sensible antioxidant and multivitamin supplements, even better. However, it is worth noting that if you’re eating a balanced diet, you probably don’t need the supplemental antioxidants and multivitamins.

So if we get back to MH’s question – no, detox diets and supplements don’t work, but following some of these diets (within reason) is probably a very healthy thing to do, so go right ahead.  Don’t bother with detox supplements, they definitely don’t work.  Instead just take a good multivitamin or some antioxidants.  When you find yourself loosing weight and feeling great, it’s not because you got rid of the toxins in your body – it’s just good nutrition.