People who cycle to work have a substantially lower risk of developing cancer or heart disease or dying prematurely, and governments should do all they can to encourage more active commuting, scientists said on Thursday.

In a study published in the BMJ British medical journal, the researchers found that cycling to work was linked to the most significant health benefits - including a 45 percent lower risk of developing cancer and a 46 percent lower risk of heart disease compared to non-active commuters.

Walking to work was linked to a 27 percent lower risk of developing heart disease and a 36 percent lower risk of dying from it, though it also appeared to have no effect on cancer risk or overall premature death risk, the study showed.

The research involved 264,377 people with an average age of 53 whose data forms part of the UK Biobank - a database of biological information from half a million British adults.

Since the study was observational, no firm conclusions can be drawn about cause and effect, the researchers said. Its findings could also be affected by some confounding factors, they added, including that the mode and distance of commuting was self-reported, rather than objectively measured.

However, "the findings, if causal, suggest population health may be improved by policies that increase active commuting, particularly cycling", they said.

These would include creating more cycle lanes, introducing more bike buying or hiring schemes, and providing better access for cyclists on public transport.

Lars Bo Andersen, a professor at the Western Norwegian University of Applied Sciences, who was not directly involved in the research but wrote a commentary on it in the BMJ, said its findings "are a clear call for political action on active commuting", saying this had the potential to significantly improve public health by reducing rates of chronic disease.

"A shift from cars to more active modes of travel will also decrease traffic in congested city centers and help reduce air pollution, with further benefits for health," he said.