MY MENTION OF THE SHANGRI-LA DIET produced a wave of email from people saying they’d lost a lot of weight on it, painlessly.

I’m . . . well, not exactly skeptical, but unpersuaded. That’s because whenever I mention any diet I get email like that. People say that diets don’t work, but that’s a half-truth: in fact, pretty much every diet works, if you stick to it. It’s the sticking to it that’s hard.

I follow the “eat less, exercise more” diet, and that works pretty well, as long as I stick to it. I’ve been reading the book, though, and it looks fairly sensible. For me, exercise is key: Not only is it good in itself, but I tend to eat better when I’m exercising regularly.