Johannesburg — Riding bicycles and eating less meat will be good for the planet and good for your health, research published by The Lancet shows.

"One widely held view is that implementation (of strategies to cut greenhouse emissions) would prove socially uncomfortable and economically painful. But ... if properly chosen, action to combat climate change can, of itself, lead to improvements in health. The news is not all bad," it said.

A special series on climate change and health, released ahead of this month's United Nations (UN) summit in Copenhagen, tries to quantify the health benefits from measures to cut greenhouse gas emissions in four sectors -- electricity generation, household energy, transport and food.

At the same time, doctors around the world -- including SA -- have launched a lobby group called the International Climate and Health Council that aims to get health professionals more involved in the debate.

"Climate change has multiple implications, all of which can affect health," said one of the founding members, Zephne van der Spuy, president of the South African Colleges of Medicine.

It has already lobbied the UN and will write to politicians likely to attend the summit, including Water and Environmental Affairs Minister Buyelwa Sonjica, urging them to take action to cut carbon emissions and promote low- carbon lifestyles.

"Politicians may be scared to push for radical reductions in emissions because some of the necessary changes to the way we live won't please voters," said Dr Fiona Godlee, editor of the British Medical Journal.

"Doctors are under no such constraint. On the contrary, we have a responsibility to warn people how bad things are likely to get if we don't act now.

"The good news is that we have a positive message: what is good for the climate is good for health."

The Lancet series gives doctors some of the ammunition they need to persuade politicians to take action.

The study on transport, which accounts for almost a quarter of fossil fuel greenhouse gas emissions, considered various scenarios with cars being replaced to varying degrees with bicycles and walking in London and Delhi.

More active travel in London could see the levels of heart disease and stroke fall 10%-20%, breast cancer drop 12%-13% and an 8% decline in dementia.