"The hunger is just in my head"

Every diet tells you, in one way or another, that the hunger isn't real. It's habit, or boredom, or emotional, or your body lying to you. Drink some water. Wait twenty minutes. The hunger on a diet is a thing to be seen through.

Sumithran's finding in the last chapter was that hunger rose after weight loss and stayed risen for a year, and that the rise went with measured changes in the hormones that produce it. That isn't hunger in your head. It's hunger in your blood, and it was put there by the weight loss, and telling yourself it isn't real is telling yourself something false about your own body.

There's a study of what the rules themselves do, apart from the weight. Janet Tomiyama, Traci Mann and colleagues, in 2010, took a hundred and twenty-one women and assigned them for three weeks to one of four conditions. Some restricted their calories to twelve hundred a day and tracked them. Some tracked but ate normally. Some ate twelve hundred calories from food provided, without tracking. Some did neither. Restricting calories raised the body's output of cortisol, a stress hormone. Tracking calories raised how stressed people said they felt. So the two halves of an ordinary diet, eating less and keeping count, each produced a form of stress on its own, in three weeks, in women who weren't otherwise unwell.

Put those together and the diet looks like this. It raises hunger through the weight it takes off, and it raises stress through the rules it imposes, and then it tells you the hunger is imaginary and the stress is weakness. A person in that state on a Thursday afternoon with a box of biscuits open on the desk isn't failing a test of character. They're a hungry, stressed person who's been told their hunger doesn't count, meeting a biscuit.

I'd like you to try trusting the hunger, in a specific way. Not obeying every impulse, which isn't what hunger is. Treating the plain feeling of an empty stomach as information about your body rather than as an enemy. The ordinary week in chapter 19 is built on eating when you're hungry at meals and not skipping them, and it's built that way because the NHS says skipping meals leads to snacking, and because the alternative, which is fighting a real signal all day, is what the envelope records the results of.