After overeating: what to do the next day.

Monday morning, after a big weekend, and the scales read higher than on Friday. You wonder what to do after overeating. Two ideas usually come up: skip meals today, or start again next Monday.

'I'm still paying for the weekend,' people I work with often tell me, even three days later. That's all-or-nothing thinking. Either you follow the plan to the letter, or you've blown it and have to make amends. That can do more harm than the dinner.

How to spot all-or-nothing thinking

• 'I've blown it now.' One unplanned pudding and the whole day is a free-for-all.
• The punishment. Next day you skip meals, or run for two hours.
• The scales every morning. You weigh yourself daily, and the number sets your mood.

Does one day of overeating make you gain weight?

Very little. The next day's number is usually almost all water, and fat is a small part of it.

The sugar store. Pasta, pizza and puddings top up the store in your muscles and liver, and each gram brings about three grams of water. After weeks of careful eating that store was half empty, and one evening can fill it.

Salt. Restaurant food is often saltier than home cooking, and salt makes you hold fluid. In one day your weight can swing by two or three kilos from water and food.

The fat sums. A kilo of fat holds roughly seven thousand calories. That's an estimate, and you'd have to eat it all on top of what you burn. One dinner rarely gets there. Back on your usual meals, store and fluid tend to go within days.

A holiday is different. Two weeks of excess can leave something real. Even then, a crash diet rarely pays, because kilos lost in a hurry tend to come back.

What to do at your next meal

The damage usually starts when you try to even things out. Five strict days and two loose ones may match a steady week for calories, but they get you used to the swings.

A normal meal. What to eat the day after overeating? What you'd have eaten anyway. A savoury breakfast of eggs, Greek yoghurt and nuts, then vegetables and protein before carbs at lunch. A skipped meal tends to raise your hunger hormone, and by evening you may be back where you started.

Move as usual. Your planned workout, plus ten to fifteen minutes on foot after meals. If training turns into a punishment, you may well give it up.

The scales, on their day. When to weigh yourself after overeating? At your usual weigh-in, once a week, before breakfast. If that's the morning after the dinner, wait a couple of days.

Find the cause, without blame. What came before? Too strict a week, a skipped lunch, short nights, a table where saying no was hard. Tell whoever is helping you. Once you know the cause, you know what to change.

Overdo it once and carry on, and that's that. If it happens every week, look at the other days. Often they're too strict, and they're the ones to change.