Want to live forever but you’re short of time and money to invest in your immortality? Well here are a couple of free and simple tips for staying healthy long enough for medical technology to catch up with biological aging. Pull back those curtains (or raise those blinds) and open the windows - plenty of fresh air and sunlight kills more bugs than a deep clean.

To you and me, it seems obvious that a good dose of fresh air clears out the lungs and must have health benefits. To scientists they call this the Open Air Factor (OAF). It was first discovered at Porton Down – the UK military’s chemical and biological research centre. And for those interested the effect comes from hydroxyl radicals produced by the natural reaction of ozone and olefins in the air.

Even at extremely low concentrations these hydroxyl radicals are able to kill microorganisms suspended in the air. And that includes bacteria that get mixed up in the air when beds are made and curtains are drawn. In fact, one company produced a machine that produced the Open Air Factor and showed it reduced the bio-burden in the air by 80%. Unfortunately that company (Aerte , previously Inov8) has now gone bust – but I will be trying track down a similar system that could be used at home.

In addition, ultraviolet light has been shown to kill bacteria lurking on surfaces – with some hospitals utilising robots that UV disinfect rooms between patients. But UV is also present in sunlight – so as well as boosting vitamin D when it lands on your skin it’s also good for cleaning the home.

For the best results, at least do this in your bedroom. You spend about a third of your life in bed so make sure you’re benefiting from the natural disinfection characteristics of fresh air and sunlight. And it doesn’t cost a penny!