Editor-in Chief, Nature

I've changed my mind about the use of enhancement drugs by healthy people. A year ago, if asked, I'd have been against the idea, whereas now I think there's much to be said for it.

The ultimate test of such a change of mind is how I'd feel if my offspring (both adults) went down that road, and my answer is that with tolerable risks of side effects and zero risk of addiction, then I'd feel OK if there was an appropriate purpose to it. 'Appropriate purposes' exclude gaining an unfair advantage or unwillingly following the demands of others, but include gaining a better return on an investment of study or of developing a skill.

I became interested in the issues surrounding cognitive enhancement as one example of debates about human enhancement — debates that can only get more vigorous in future. It's also an example of a topic in which both natural and social sciences can contribute to better regulation — another theme that interests me. Thinking about the issues and looking at the evidence-based literatures made me realise how shallow was my own instinctive aversion to the use of such drugs by healthy people. It also led to a thoughtful article by Barbara Sahakian and Sharon Morein-Zamir in Nature (20 December 2007) that triggered many blog discussions.

Social scientists report that a small but significant proportion of students on at least some campuses are using prescription drugs in order to help their studies — drugs such as modafinil (prescribed for narcolepsy) and methylphenidate (prescribed for attention-deficit hyperactivity disorder). I've not seen studies that quantify similar use by academic faculty, or by people in other non-military walks of life, though there is no doubt that it is happening. There are anecdotal accounts and experimental small-scale trials showing that such drugs do indeed improve performance to a modest degree under particular circumstances.

New cognitive enhancing drugs are being developed, officially for therapy. And the therapeutic importance — both current and potential — of such drugs is indeed significant. But manufacturers won't turn away the significant revenues from illegal use by the healthy.

That word 'illegal' is the rub. Off-prescription use is illegal in the United States, at least. But that illegality reflects an official drugs culture that is highly questionable. It's a culture in which the Food and Drugs Administration seems reluctant generally to embrace the regulation of enhancement for the healthy, though it is empowered to do so. It is also a culture that is rightly concerned about risk but wrongly founded in the idea that drugs used by healthy people are by definition a Bad Thing. That in turn reflects instinctive attitudes to do with 'naturalness' and 'cheating on yourself' that don't stand up to rational consideration. Perhaps more to the point, they don't stand up to behavioral consideration, as Viagra has shown.

Research and societal discussions are necessary before cognitive enhancement drugs should be made legally available for the healthy, but I now believe that that is the right direction in which to head.

With reference to the precursor statements of this year's annual question, there are facts behind that change of mind, some thinking, and some secular faith in humans, too.