After smoking, alcohol is the next public health behavioural challenge of our generation. There have been moves at national and international level to recognise and tackle the problem of alcohol misuse. Its consumption is increasing, particularly among younger adults.

Alcohol consumption increases risk of liver disease. However, levels and patterns of alcohol consumption do not fully explain the rises in liver disease mortality that have occurred in some countries.

A recent Scottish study showed that body mass index(BMI) is related to liver disease, suggesting that the current rise in overweight and obesity may lead to a continuing epidemic of liver disease. Looking in the same cohort of men in Scotland, the same authors found that raised BMI and alcohol consumption are both related to liver disease, with evidence of a supra-additive interaction between the two. This led the study authors to suggest that BMI-specific "safe" limits of alcohol consumption may need to be defined. In the same issue of the BMJ, a study of 1.2 million middle-aged women in the UK showed that 1800 of the women developed or died from liver cirrhosis during follow-up. Increasing BMI was associated with increased liver cirrhosis, with a 28% increase in risk for every 5 unit increase in BMI. In addition to the effect of BMI, the absolute risk of liver cirrhosis increased as alcohol intake increased. The authors estimated that 17% of liver cirrhosis is due to excess body weight, compared to 42% due to alcohol.

An accompanying editorial makes the point that “compared with the risk of cardiovascular events in middle aged people, an absolute risk of one case per 1000 people over five years for liver cirrhosis seems low. However, this absolute risk still represents a substantial burden of illness for the patients concerned and for the health service”. The upshot is that alcohol and obesity in combination cause liver cirrhosis, another negative consequence of unhealthy lifestyle. Reductions in alcohol consumption and obesity are currently the only way we can prevent non-viral liver disease.