The previous policy of setting a minimum unit price would have had a 40-50 times greater effect, particularly among harmful drinkers, say researchers.
Increasing the price of alcohol has been shown to be effective in reducing both consumption levels and harms, and the UK government has been considering different policy options for price regulation in England and Wales.
In 2010, the government announced a ban on "below cost selling" to target drinks which are currently sold so cheaply that their price is below the cost of the tax (duty and VAT) payable on the product. Plans to introduce a minimum unit price for alcohol of between 40p and 50p per unit were shelved in 2013.
So researchers at the University of Sheffield decided to compare the effects on public health in England of these two alcohol policies.
Using a mathematical model alongside General Lifestyle Survey data, they estimated changes in alcohol consumption, spending, and related health harms among adults for 2014-15.
The population was split into subgroups of moderate, hazardous, and harmful drinkers, according to weekly consumption guidelines.
The team estimate that below cost selling will increase the price of just 0.7% of alcohol units sold in England, whereas a minimum unit pricing of 45p would increase the price of 23.2% of units sold.
Below cost selling will reduce harmful drinkers' mean annual consumption by just 0.08%, around three units per year, compared with 3.7% or 137 units per year for a 45p minimum unit price (an approximately 45 times greater effect).
The ban on below cost selling has a small effect on population health, they add - saving an estimated 14 deaths and 500 admissions to hospital per year. In contrast, a 45p minimum unit price is estimated to save 624 deaths and 23,700 hospital admissions.
Furthermore, most of the harm reductions (for example, 89% of estimated deaths saved per year) are likely to occur in the 5.3% of people who are harmful drinkers because they buy the greatest share of cheap alcohol.
Additional analyses suggest that the relative scale of impact between a ban on below cost selling and a minimum unit price "are robust to a variety of assumptions and uncertainties," say the authors.
Despite some study limitations, the authors say they found "very small estimated effects for banning below cost selling" and showed, in comparison, "that a minimum unit price of 45p would be expected to have 40-50 times larger reductions in consumption and health harms."
In an accompanying editorial, Tim Stockwell from the Centre for Addictions Research at the University of Victoria in British Columbia, Canada says minimum pricing in Canada "has been associated with significant reductions in alcohol related harm." Furthermore, Canadian research suggests that the estimated benefits of minimum unit pricing in the Sheffield model are "highly conservative."
Unlike Canada, he wonders why there has been such industry opposition to minimum unit pricing in Europe. "Could it be that minimum unit pricing in the EU would set some dangerous precedents for commercial vested interests," he asks?
Either way, the outcome of a case pending at the European court of justice will have major implications for the future of public health in Europe, he concludes.