In the 1850s, the average life expectancy in the US at birth was only 40 years old. Now, the average American can expect to live until at least 78. Recent medical research has teased us with the promise of extending human life further. But, what are the implications of this new medicine and what consequences would it have upon society?

Films, such as Logan’s Run and Soylent Green, have painted grim visions of an overpopulated future, where drastic measures are taken to control these overcrowded worlds and their scarce resources. The need for strict population control is not pure fantasy – until recently, China had the One-Child Policy, due to their booming population in the 1970s.

One might think that a longer-living society would lead to an increase in population, but the reality is quite different. Population growth is more determined by birth rates than mortality rates. “In the very short term, falls in mortality do create population growth,” observes Jane Falkingham, professor and director of the Centre of Population Change at the University of Southampton. “In the longer period, it is fertility that is the engine rather than mortality.”

Recent clinical trials in mice have shown diabetic animals given the drug metformin, first introduced in 1957, are living longer than non-diabetics, who did not take the drug. And it’s been suggested that metformin could protect against basic ageing itself, and not just type 2 diabetes.

However, there are some possible pharmaceutical treatments that may not only protect against ageing, but actually reverse the effects of ageing itself.