What does "detox" actually mean?
The word "detox" comes from the Latin or English. (Detoxifying) and means to detoxify. The term describes some processes and has a wide range of applications. So does it describes:
→ Physiological detoxification, i. the metabolism of toxins
→ The degradation of xenobiotics within the cells
→ Purifying the body in alternative medicine
→ The phase of withdrawal in dependence disorders
→ The sewage cleaning
In the sewage cleaning cadmium, zinc, lead, as well as chromates, cyanides and nitrites are removed from the water cycle. In the case of withdrawal, detoxification is the phase in which addiction is lowered or left out altogether. This allows the body to start detoxifying, as no new toxic substances are supplied.
What is biological detoxing?
Detoxing is usually associated only with alternative medicine. If one hears of "detox cures" or "detoxing", the detoxification of the body is u.a. by systematic diets or esoteric practices such as e.g. meant by healing stones. They should purify the body and help with the natural detoxification of our organism. Physiological detoxification is the process by which toxins are biotransformed, harmless or at least less toxic. This is done through the liver and kidneys. Biotransformation mainly refers to the transformation of non-excretable, fat-soluble substances into precipitable water-soluble substances. 
Why does not "detox" describe all processes, though that does mean it?
While the word "detox" is more relevant than alternative medicine, it is mainly associated with it, making it unsuitable for designating the actual degradation of toxins. It is a difference whether plant or animal poisons, or synthetic substances from our environment or private life, e.g. Alcohol or caffeine can be processed, or maybe you want to lower your cholesterol level. "Detox" has long been almost as good as the alternative medicine, and the "detoxification" is, in the vernacular, for a long time no longer suitable for the reduction of actual poisons. 
What kind of problems arise from this?
Language is an aspect of people that changes as fast as people themselves. Over time, words can change in their pronunciation, spelling, but also in their message. "Detox" and the German word "detoxification" are in the vernacular, in their original meaning meanwhile so modified that they, despite their logical implications, but usually do not have to mean what they should. So anyone can use "detox" as a promotional tool, and has to do only minimal effects to make it legitimate. If one reads of detox juice diets, this is exactly what it promises, a detoxification cure. If one reads of detoxification of the blood by dialysis, this is exactly what it says. However, completely different processes. One is intended to bring blood levels up to scratch, while the other takes over the entire task of the liver and kidneys to ensure the survival of people with severe organ damage. Both detoxification processes. Both completely different. So one tends to quickly underestimate the word "detox" / "detoxification. No diet, no healing stones or cosmetics could suffice in the actual effect of detoxification, for example dialysis. Likewise, they are by far enough if you want to experience a little healthier.
What does this mean for cosmetics?
There are many cosmetics that advertise detoxification. And they are often not wrong. The skin, or the hair when dealing with toxins, whether from the environment or from your own organism, to help, to deal with them is a form of detoxification or at least the aid to it. However, one could just as well have the effect, e.g. as an antioxidant. The properties and effects that cosmetics make into cosmetics are either direct detoxification, aiding in body poisoning, or passivating detoxification (i.e., preventative protection). Finally, it is not wrong to say that a detoxifying cosmetic product works, it reinforces belief in the promised effect.
Where could you draw the line?
One suggestion would be to set certain parameters that must be met so that detox can really be seen as a detox. So products that fulfill only one task, should not be advertised with "Detox". Protecting a cosmetic with ingredients as its primary target against oxidation should therefore be labeled with its actual effect, not "detoxing". Some parameters that should be met are:
→ They should combine multiple effects, not just one or two primary ones
→ They should be applied to a larger area
→ They should be used as a regularity, not as a virtue
→ The above points are also related to the field of application, so a hand cream is no detoxing, an antioxidant, antibacterial, skin cleansing, and regularly applied anti-nickel product rather.
However, how these parameters should be accurate depends on your personal feelings. With all this information, one can still say nothing conclusive about the "is" or "is not". It remains for each of themselves to make a demarcation, but now this is certainly a bit easier.
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