The Truth About Testosterone in War, Sex, Money and Men


by Joe Herbert
OUP (23.75)

Testosterone makyth manliness. There's sex: in men, the higher the levels of testosterone, the more sexual partners they have. There's money: higher levels of testosterone in male traders in the morning before work correlate with higher profits. And there's aggression: young girls exposed to extra testosterone in the womb (a condition called CAH) romp much more violently in the playground.

But, Joe Herbert argues, it's not all so simple: in CAH boys there's no change in aggression, and small doses of testosterone given to mature women can make them more generous. In war, stress and fear actually combine to reduce male levels of testosterone enormously. And while winning something seems to raise levels slightly, losing is much more significant; testosterone levels went up in Obama voters on election night in 2008, but the difference was nothing compared to the plunge among McCain supporters.

There is a tendency in popular science writing to treat hormones simplistically, calling serotonin the "happy chemical" or oxytocin the "cuddle hormone". But Herbert's book is refreshingly sensitive to the gamut of testosterone's effects, which are not felt in just a single way, or at a single time.

Prenatal testosterone seems to have a different function to the burst of testosterone in male children between months four and six of their infancy when their levels rival their father's. Then the hormone all but disappears until bursting into action again at puberty. Properly attentive to such quixotic data, Herbert must frequently acknowledge "we just don't know", which he does honestly – but perhaps unsatisfyingly often.

Herbert doesn't, however, escape another brand of reductionism that plagues literature at the more serious end of the "pop" spectrum, for "the brain" is often the subject of sentences like "the human brain has manufactured the financial world". The brain can't in itself "do" anything; only people with minds can. This metaphorical shorthand in a book asking to what extent we are shaped by testosterone seems either lazy or unconsidered.

At no point in Herbert's account do choice, will or the relationship between our brains and our consciousness come into it. And those things matter. Human endeavour is based on the assumption that we can act deliberately and meaningfully. To assume we can't risks depriving us, and Herbert, of that dignity.