"It'd be a waste"

For a lot of people this is the belief that does the most work, and it was put there early. You may have heard "Finish what's on your plate" at several thousand childhood meals. You may have been told about children elsewhere who had nothing. Pudding may have depended on a clean plate. Your parents or grandparents may have lived through times when food was short, and their rule made complete sense in their world.

The feeling behind it is a good one. Wasting food is a bad thing. It costs money, someone grew it and someone cooked it, and throwing it out is careless. I'm not going to argue you out of caring about that.

The argument is with where you think the waste happens. Consider the last third of the lasagne square, the part after enough. Your body didn't need it. Eaten, it does you no good and some mild harm. In the bin, it does you no good and no harm. In neither case does it feed a hungry person. The food is wasted either way. If you eat it, the waste goes through you on its way out. You've used yourself as the bin.

The real waste happened earlier. It happened when too much was cooked, or too much was served, or too much was ordered. That's also where the fix is. Once the food is on the plate and you've had enough, no good option for that food remains at the table. There are a few bad ones, and eating it when you don't want it is one of them.

There are usually better options than the bin, though, and they're so ordinary that the clean-plate rule skips past them. Leftover lasagne is tomorrow's lunch, and many people think it's better on the second day. Most cooked food keeps in a fridge for a day or two and in a freezer for months. In a restaurant you can ask for a box, and nobody minds. A third of a portion in a box is a whole small meal tomorrow, so it hasn't been wasted at all.

Restaurants bring out a related belief, which is about money. You've paid for it, so you'd better eat it. This is the same mistake that keeps people sitting through a bad film because they bought the ticket. The money is spent whichever you do. What's still open is whether the next ten minutes make your evening better or worse. If you're comfortable now and would be overfull after finishing, then finishing means you pay the bill and get an uncomfortable evening as well.

Then there's the cook. "She'll be hurt if I leave some." Sometimes that's true, and chapter 9 deals with hosts. Mostly what a cook wants to know is that you enjoyed it. You can tell them so, and ask to take some home. That tells them more than a clean plate would.

I mentioned children in the cautions. There's a reason to go gently on the clean-plate rule with them. As I see it, the rule teaches a child to stop eating when the plate is empty and not when they've had enough. One survey of 993 American adults found that people with a stronger habit of clearing their plates tended to weigh more, even allowing for many other factors. It was a single survey, based on people's own reports, and can't show that one causes the other. I mention it because it fits the argument of this book. The rule hands the decision about how much you eat to whoever filled the plate.

The practical upshot is a change in where you aim your dislike of waste. Aim it at the shopping, the cooking and the serving, where it can do some good. Cook the big lasagne, by all means, but plan on two meals from it. Then, when you've had enough and there's food in front of you, the thrifty move is a box with a lid.