Answer:
You should not sell unprescribed medication to people is illegal because they could be considered drugs. It is unsafe because they do not need it, or if they did they could have their doctor prescribe it to them and they you would not need to sell it to them.
They usually contain a diuretic. A diuretic increases the amount of water lost from the body. Since the body is made up of 80% water, the person will see some weight loss. Once the person stops taking the supplement the weight will be regained quickly.
It sometimes is and sometimes isn’t. The issue is when avoidance becomes the standard reaction to a stressor or conflict. Avoidance in general is good short term, but it is a better thing to confront the problem. Otherwise you will have the problem fester.
Heart disease
Cancer
Stroke
Accidents
The slowest drug absorption/response is definitely oral/digestion route.
The fastest drug response time route would be intravenous, the drugs directly enter the blood so it can work instantly. Snorting/inhaling drug still need time to be absorbed to the blood vessel. It might be fast enough if used for local response (example: asthma). The mechanism probably by mucosa diffusion so its similar to rectal or sublingual route.