As told to Niamh Leonard-Bedwell. Photograph John Carey
Almost without question, obesity is the biggest problem facing the health sector today, and it would be perfectly possible to put a stop to it in the same way that the government put a stop to smoking. After years of listening to the lies of the tobacco industry, the government began to increase the tax on cigarettes to a high level. Additionally, much more information about the dangers became available and the rate of smoking has reduced dramatically as a result. Junk food needs to be treated the same way.
It’s clear that genes play a role in health, but you can’t separate nature and nurture. There’s one gene called FTO that was first found in mice – it causes their toes to fuse together. Bizarrely, in humans, it’s an appetite gene. If you’ve got two copies of one particular DNA chain in FTO, you need to eat more before you feel full. So, if the food is available, it’s easier to eat more and put on weight. On average, people who have this weigh around 2.5kg more than people who don’t. But back in the 1950s and 1960s, before the obesity crisis began, these genes weren’t necessarily important, because there wasn’t a lot of cheap or junk food available like there is today.