The day after

This chapter isn't about hangovers. You know what a hangover is and you know what caused it. It's about the day after an ordinary evening, two glasses or three, nothing anyone would remark on.

That day has a texture that's easy to miss because it's so familiar. You're a little tired. There's a faint unease with nothing to attach itself to, so it attaches itself to an email you haven't answered. You're a little shorter with people than you'd like. If you noticed it at all, you'd call it Tuesday.

The NHS notes that hangovers often leave people anxious and low, and that if you already feel anxious or sad, drinking can make it worse. The question for a regular drinker is whether something milder happens after milder evenings.

In 2000 Matt Kushner and two colleagues reviewed the research on why anxiety problems and alcohol problems so often turn up in the same person. They concluded that each can start the other. They also proposed, tentatively, that the short-term reduction in anxiety from a drink, combined with a longer-term increase in anxiety from regular drinking and its aftermath, can set up a cycle in which each feeds the other.

I need to be careful here. Kushner's review was about diagnosable disorders and heavy use. It wasn't about two glasses on a weeknight. What follows is my interpretation. I think a fainter version of the same cycle is a fair description of ordinary regular drinking.

The mechanism, in plain terms, goes like this. Give the brain a sedative every evening and it adjusts by turning itself up slightly, so that you function normally with the sedative on board. Researchers call this kind of adjustment an opponent process. When the alcohol has gone, the turned-up setting is still there for a while. You feel it as edginess, light sleep and that unattached unease.

Now go back to the kitchen. You arrive at ten to seven carrying two things. One is the day, the meeting and the train. The other is what last night's wine left behind, which has been quietly raising your idle speed since about four in the morning. The glass settles both. Since you can only see the day, the day gets the blame for all of it, and the glass gets the credit for fixing a tension it helped to make.

This is the point where books like this one tend to overreach, so I'll mark the limit. Your job is real. So are your children, your money worries and your mother's health. Wine didn't make any of them, and stopping drinking won't make them go away. My claim is only that some part of your evening tension is left over from the night before, and that you can't tell how big a part while you're still drinking most days.

The only way to find out is to go long enough without for your baseline to settle. For dependent drinkers the NHS says withdrawal usually lasts three to seven days, with some symptoms lasting longer. For a regular drinker who isn't dependent, I'd expect two or three weeks to show you your own baseline. That figure is my estimate and not a research finding.

In the meantime the test question gets a second half. When you're wound up at ten to seven, ask what else changed when you picked up the glass, and also ask how you slept and what you drank last night.