New York, Nov 13 (IANS): Rising incomes and urbanisation around the world are driving global dietary shifts towards processed food and meat-based products that is, in turn, diminishing the health of both people and the planet, says a study.

"These dietary shifts are greatly increasing the incidence of Type 2 diabetes, coronary heart disease and other chronic non-communicable diseases that lower global life expectancies," the researchers said.

The researchers gathered information on dietary trends and environmental impacts for 90 percent of the global population.

"The links between urbanisation, increased wealth and unhealthful diets are clear," said study co-author David Tilman from the University of California in the US.

When a country industrialises, the transition from a traditional rural diet to one that includes more processed meats and more empty calories can occur quickly.

"Almost overnight, they go from a healthy diet to one that has way too many calories and leads to diabetes and heart disease," Tilman said.

Also, because people tend to eat more meat as they become wealthier, much of the expected 100 percent increase in crop production that will be required by 2050 would be used to feed not humans but livestock.

To do that, much more land will need to be cleared with the result that more habitat will be lost, more species will become extinct and increased runoff of agricultural fertilisers and pesticides will degrade streams, rivers, lakes, groundwater and oceans.

"Better diets are the solution to these big problems," Tilman added.

The study appeared in the journal Nature.