Updated

A new United Nations report says saving the environment may require people to work shorter hours in the future.

The report by International Resource Panel released Wednesday says that the amount of raw materials extracted from the Earth has tripled over the last 40 years, fueled by a growing middle class, and that will require a more efficient use of resources in order to avoid serious environmental consequences.

That increased efficiency will in turn lead to lower costs and higher economic growth which could hamper efforts to reduce overall demand, the report said.

In order to compensate for these gains in efficiency the report recommends a combination of policy initiatives including shorter working hours and pricing raw materials in way that reflects the social and economic costs of their extraction.