Doctors know that children whose mothers smoke have a higher risk of smoking during their adolescence, but they are yet to find out why. However, a recent study says it probably involves the learning of flavours. A variety of flavours are transmitted from the mother's diet to the baby through breast milk, say Julie A Mennella and Gary K Beauchamp from the Monell Chemical Senses Centre in Philadelphia, USA. They tested if smoking alters the odour and flavour of human milk. Several smoking mothers, who were lactating, were studied. The scientists collected their breast milk samples after they stopped smoking for 12 hours. Then, these women were allowed to smoke two cigarettes in some 20 minutes. The researchers collected breast milk samples four hours at 30-minute intervals. These were evaluated by a sensory panel of seven adults who evaluated the odour besides an analysis by gas chromatography for nicotine content. Both the panel and the chromatographic data showed distinct nicotine content within 30 minutes to one hour of smoking. This study offers a very strong evidence of why children of smoking mothers tend to be smokers