Although the mechanism for the high prevalence of skipping breakfast is not clear, it has been suggested that nicotine, known to have appetite-suppressant effects on the central nervous system activity, may be acting as a breakfast 'replacement' 27 . The 'altered taste' due to intensive smoking is thought to result in changes in meal pattern. Anthropometric data showed that the smokers were slimmer and had a lower BMI than the non-smokers. In spite of the fact that the energy intake was almost the same as that of non-smokers, this is in agreement with other studies 5 . The only known mechanism that can be used to explain the lower body weight and body fat among smokers is the increased metabolism theory 28 .
Metabolic rate is an important and often overlooked variable in energy imbalances.
Seventy-five per cent of total energy expenditure comes in the form of metabolism 30 . However, this study was not able to perform the dose-response analysis in order to provide conclusive evidence for the relationship between smoking and body weight. In conclusion, this study demonstrates that current smokers have a diet that is low in micronutrient intakes, especially vitamin C and carotenoid, and a high alcohol intake. Smokers appear to have different dietary habits and health behaviour. Given the prevalence of cigarette smoking is high in this Chinese elderly population, these observations should be considered in future studies where the diet-related diseases in Chinese population.