The idea behind this comes from ancient medical understanding of the four humors.
Humorism, or humoralism, is a now discredited theory of the makeup and workings of the human body, adopted by Ancient Greek and Roman physicians and philosophers, positing that an excess or deficiency of any of four distinct bodily fluids known as humors (UK: humours) in a person directly influences their temperament and health
Just as bleeding patients, vomiting and laxatives were common to balance the bodily fluids. Humorism is an idea common to most cultures. Vomiting was a very common practice amongst the Native Americas, for instance. Now, here the claim has been replaced slightly with "toxins" rather than "humors" Replacing toxin into the claim makes it seem more credible, but its not. The removal of toxins was always a large part of humorism.
TOBACCO IN FOLK CURES IN WESTERN SOCIETY
the reason for the rapidity of European acceptance of tobacco as medicine was the basic medical
theory itself, the theory of humours. Fundamentally this was the belief that only
four elements (air, fire, earth, and water) composed all things, including the human
body and its illnesses. These elements were capable of much interfunctioning, but
ideally they balanced one another. They had four basic properties which occurred
in combinations (moist, hot, dry, and cold—that is, water has the combined properties
of moist and cold, fire of hot and dry, and so forth); and they corresponded to
the four seasons of the year (spring, summer, fall, and winter). They appeared in the
human body, together with their properties, in the forms of **four humours—bloodj
yellow bile, black bile, and phlegm—**and when the humours balanced, the human
being was healthy. Sickness resulted from an imbalance of these humours
And Vittich wrote that there could he no doubt about tobacco's
ability to "cleanse all impuritites" and do away with "every gross and viscous humour."
Vomiting balances the yellow bile.
According to Wikipedia on the "Misuse of Toxin"
When used non-technically, the term "toxin" is often applied to any toxic substance, even though the term toxicant would be more appropriate. Toxic substances not directly of biological origin are also termed poisons and many non-technical and lifestyle journalists follow this usage to refer to toxic substances in general.
In the context of alternative medicine the term is often used to refer to any substance claimed to cause ill health, ranging anywhere from trace amounts of pesticides to common food items like refined sugar or additives such as monosodium glutamate (MSG).
Toxins are poisons produced by your body or by another plant or animal that would be harmful to you. Most toxins thus are the ones produced during respiration (CO2) or other normal bodily processes. If C02 builds up, known as hypercapnia, you will die for example. In this case of course, C02 is expelled when you exhale.
As for vomiting specifically. This is one way the body can get rid of toxins, but only if it is something very toxic you just ate, because vomiting only expels food from the stomach. Food only stays in your stomach for a few hours and environmental toxins can be absorbed before this time. Obviously if you eat poison on accident, it is appropriate to induce vomiting if it isn't acidic or basic (bleach, cleaning products, drain cleaners). Poison Control specializes in answering questions about when to throw things up. Guidelines for Ipecac. The toxicologists here are saying its rarely useful for anything, because of the fast absorbtion and because vomiting isn't very useful at expelling poison even in the most dire instances, so its best to always call.
Through the pathway of vomiting it would not be possible to remove substances that might cause ill health suggest as MSG or trace pesticides, either, unless the intention is to do this by causing the person simply not to eat. Starvation is very much less beneficial to ones health than any benefit this is supposed to be causing. Consistent vomiting, known as bulimia, is very bad for one's health. Effects include:
- Chronic gastric reflux after eating
- Dehydration and hypokalemia caused by frequent vomiting
- Electrolyte imbalance, which can lead to cardiac arrhythmia, cardiac arrest, and even death
- Esophagitis, or inflammation of the esophagus
- Boerhaave syndrome, a rupture in the esophageal wall due to vomiting
- Oral trauma, in which repetitive insertion of fingers or other objects causes lacerations to the lining of the mouth or throat
- Gastroparesis or delayed emptying
- Mallory-Weiss tears
- Enlarged glands in the neck, under the jaw line
- Peptic ulcers
- Calluses or scars on back of hands due to repeated trauma from incisors
- Constant weight fluctuations are common
The erosion on the lower teeth was caused by bulimia. For comparison, the upper teeth were restored with porcelain veneers.
The frequent contact between teeth and gastric acid, in particular, may cause:
- Severe dental erosion
- Perimolysis, or the erosion of tooth enamel
- Swollen salivary glands
- Constant vomiting can lead to gastroesophageal reflux
Further reading on the health consequences of bulimia, here:
National Eating Disorders Association