Doctors and pharmacists have warned against taking health supplements that supposedly help reduce the harmful effects of smoking and drinking.
They are worried that some may be misled into overindulging.
Manufacturers of one product, a green tea extract, claim it can help those exposed to tobacco smoke, air pollution and exhaust fumes by strengthening their lungs and immune system. The supplement has been on sale for several months, backed by newspaper and television promotions.
TV adverts for another product, a dietary fibre, say it absorbs alcohol in the stomach and reduces the amount that enters blood vessels.
Dealers selling the products in Hong Kong have acknowledged that clinical tests have not yet proved their effectiveness.
Phyllis Poon, marketing manager of the company that sells anti-smoke supplements, admitted that clinical tests conducted in the US were not 'good enough'. After the company consulted local doctors, it withdrew claims in latest promotions last month that the product could reduce levels of cancer-causing substances.