There are a lot of Detox diets out there and many of them seem to give contradictory advice. The reported facts are valid but often the connection between the facts and the truth is myth. Some of these diets are simple logical healthy diets while others go to the extreme in order to remove toxins from the body. Some of the more extreme diets are likely unhealthy. It is true that we absorb toxins in our bodies. We acquire these toxins through the food we eat and the air we breathe. We have mechanisms in our bodies to remove these toxins. Mucus removes dust and debris from the lungs and our digestive system, liver, and kidneys remove many of the toxins we ingest. There are times when our exposure to toxins exceeds our ability to remove them and that is when some form of detoxification makes sense. To detoxify the body you can still eat regular foods. You need to identify the source or sources of the toxin and reduce or remove them from your diet but you can replace these foods with others. If mercury is a concern for example, one common source is tuna. Cutting tuna out and adding in a different low mercury fish will detoxify your body without having to "diet". There are things we can all do to continually help our bodies remove toxins. The first is drinking water (good potable water without a lot of minerals) - most city tap water will do. The second is eating fiber - either supplementing or eating foods high in it. The water will flush out the blood through the kidney filtration system removing heavy metal ions and other toxins with the urine. The fiber will effectively scour out the surface of your intestines removing any decaying matter, dead bacteria and intestinal cells leaving fresh cells free and clear to absorb properly. A varied diet will reduce the chances of toxic levels of material getting in to the body in the first place as a single source will concentrate any toxins it contains.
Detox diets actually reset and direct the hormones to detoxify the body that's why they are so specialized. Ordinary or casual healthy practices will not be very effective as the body and the brain are already accustomed to them, so they will not have drastic effect in the body. What they will only do is improve the mechanisms that are already ongoing in the body, but not redirect or manipulate them.