I’m assuming that you’re quite fat. But don’t go and change yourself. UK scientists have discovered that fat people are more cheerful than their thin peers. I thought this was just a revivification of the ancient wisdom that says you shouldn’t go on a totally fat-free diet because your brain needs its fat surround to keep from crashing against your skull. That makes you depressed. But you don’t have to be obese to maintain this fatty covering. Nor is this a reworking of the slightly less ancient study that found that people with notable self-control, people who weren’t “appetitive”, were more likely to be depressed.

The people enjoying themselves are the fat, jolly ones. The people who worry about how they look, and what people think of them, and what God might think, and whether drinking too much will turn out to be a signal that they are bound for hell — those people don’t enjoy themselves so much.

The new research merely asked whether fat people kill themselves. Are they prone to depression? The answers were no. Not only are you less depressed when overweight, it works in proportion. The fatter you get, the less likely you are to commit suicide. It’s possible that you could be getting morbidly obese as an incremental form of suicide. Research doesn’t relate.

Doctors guessed that thin people were depressed with the effort of keeping thin. It’s feasible but there are plenty of fat people on diets who are making all that effort and failing, and they seem pretty cheerful. We have to fall back on “comfort eating”. You do actually gain comfort from eating.

Consider the pleasure derived from food. There is the comforting taste of something with a heap of fat, the more arcane pleasures of the gourmet, which are prissier and rarer; and the warped pleasure of self-denial.

What makes this fat/happy curve so surprising is that fat people have a horrible time at the hands of society. It was found that they were less likely to land jobs, and doctors made moves to stop treating them for joint replacements. But still they smile. If there is a correlation between body mass index and mental health, when, exactly, are we going to start charging skinny people for their own Prozac huh?