Men still age faster than women. But although reduction in smoking has narrowed the gap, that is not entirely the result of lifestyle choices. Those are the main conclusions of a study by Finnish researchers. They looked at younger and older adults, including opposite sex twins who had grown up in the same environment and shared half of their genes. The male sibling was about one year biologically older than his sister. The researchers believe the difference may be explained but the beneficial effects of the female sex hormone oestrogen on health and – to a small extent – men’s larger body size.