Climate change debates often dwell on the price of things that go round and round, like power-generating turbines or the wheels on the bus. That's where the tie to climate pollution is clearest: Burn. Churn. Emit.

That may not be enough. Every year that global carbon dioxide levels go up, countries need more ways to cut emissions. A new paper published Wednesday in the journal BMC Public Health reasons that growing food, the source of about one-third of carbon dioxide pollution, should also be a target for taxation.

The good news is they're not talking about food that's good for you. The items most responsible for greenhouse gas emissions are often the least healthy, particularly red meat. The point is that "small, incremental changes to people's diets," in the words of lead author Adam Briggs, can bring significant reductions in emissions, improvements in health, and increases in public tax revenue.

But the UK researchers aren't content with keeping carbon compounds out of the atmosphere. They want to keep them off your midsection, too.

In recent years, some policymakers have begun to treat CO2 cuts as a fringe benefit of programs aimed more directly at improving human health. Think of China's smog-choked cities. The primary motivation to clear the air is arguably that urban residents are fond of breathing, but the fringe benefit is the reduction of greenhouse gas emissions.

That's similar to the reasoning of the UK paper's authors, and a growing number of British voices (including the prominent think tank Chatham House) drawing attention to the climate impact of food. The ideal is a single policy that can nail two targets: unhealthy eating and climate change. Basically, methane-belching cattle and sheep are pretty bad all the way around.

"The aim of the paper is not to make everyone become a vegetarian," said Briggs, a public-health researcher at the University of Oxford. Nobody's going to starve, since there's plenty of pork, chicken and fish to offset cuts in beef and lamb.

The researchers also envision a 20 percent U.K. tax on sugar and sugary soft drinks to bring in more tax revenue while encouraging people to make healthy choices (alcohol and coffee are spared).

The results of their study show that a nudge here and there can have a big effect on what a nation eats. They look at four scenarios, with the most pronounced results coming from the last. In that case, taxes are levied on foods with pollution footprints bigger than the U.K. average, proceeds are used to subsidize food with smaller-than-average footprints, and sugary drinks are taxed.  (In real life, legislation could be written that makes sure a regressive tax doesn't disproportionately hit the poor.)

As a result, the researchers project 2,000 fewer U.K. deaths—thanks to diets higher in fiber and lower in fat—and 16.5 megatons of averted CO2 emissions.