A recent study on the cancer risks of drinking alcohol has been widely reported in news headlines. The Times headline is:
Half-bottle of wine a night ‘as bad as three cigarettes’
The BBC summarise slightly differently:
Drinking one 750ml bottle of wine a week increases the risk of developing cancer over a lifetime by the equivalent of 10 cigarettes a week for women and five for men, a study says
They're both reporting the same study.
Not every expert agrees. David Spiegelhalter says (my emphasis):
If cigarette-equivalents were to be used to communicate the cancer risk of alcohol consumption, it is vital that their impact is properly evaluated to check they do not produce unreasonable concern – particularly as the overall health effect of moderate alcohol consumption is still contested.
Other experts' views can be found from the same source.
I've used one specific way of expressing the key issue as the headline for the question. But don't get bogged down with that specific formulation: other reports were all paraphrases of the results from the same study.
The key question is: given all we know about the harms of alcohol (which are very contested for moderate consumption) is the comparison with smoking (where the harms are clear and mostly uncontested) fair and a good summary of the totality of evidence?