Your weekly average

Your average weekly weight is the top-level number I use to detect changes, diagnose problems and judge progress. I call it AWW for short. This one simple number can help you:

• see how close you are to losing fat at full speed,
• detect weight trends early and ask why,
• correct your estimate of what you burn in a day (your TDEE),
• check that you're eating the right amount when you're maintaining.

Why not just read the scale?

Because one weigh-in is mostly noise. A salty dinner, a carb-heavy day, a hard workout or the time of the month can each move the scale by a pound or more overnight, and none of that is fat. My own weigh-ins swing about 1.2 lb from one morning to the next.⁠[1]

Seven weigh-ins averaged together cancel most of that out. What's left is much closer to the truth.

How to weigh in

First thing every morning: use the bathroom, then step on the scale before you eat or drink anything. Same scale, same spot on the floor, same amount of clothing. Write the number down, then forget about it. The single number doesn't matter.

Weighing in every day sounds obsessive, but it's the opposite. When you only weigh in once a week, that one noisy number carries all the weight. When you weigh in daily and only look at the average, no single morning can ruin your day. In studies, people who weigh themselves regularly lose more weight, and most don't feel worse for it.⁠[2] If the number starts to wreck your mood, or you have a history of disordered eating, weigh in less often or not at all.

Tracking it in a spreadsheet

Open a Google Sheet. Make a row for each week and a column for each day. Average each row, then subtract last week's average from this week's. Here's what three of my weeks looked like:

All weights are in pounds. Look at the first week: Tuesday to Wednesday jumped 3.7 lb. If that had been my only weigh-in of the week, I'd have thought something was badly wrong. The average barely noticed.

Two averages worth knowing

The calendar week average

A calendar week average starts with Monday morning's weigh-in and ends with Sunday morning's. Notice that this means it reflects what you ate and did from Sunday morning through Saturday night.

Here's how it plays out. Yesterday was Sunday, and my average for the week locked in at 175.7 lb. This morning, Monday, I weighed 174.4 lb. So far this week I'm down 1.3 lb against last week. As I weigh in through the week, that number will move up or down until it locks in next Sunday.

The calendar week is the one to keep a history of, because each week is finished and comparable.

The last 7 days average

It's also useful to compare the average of your last 7 days with the 7 days before that. This one is always based on a full week of weigh-ins, so it doesn't jump around early in the week the way a calendar week with only one or two weigh-ins does.

On that same Monday, my last 7 days against the 7 before was down 0.9 lb. That's a more realistic read of the pace I was going at than the 1.3 lb from a single Monday weigh-in. Tomorrow it'll barely change, because it'll again be 7 weigh-ins compared with 7 more.

Because everything here runs week by week, I find the last 7 days average the more motivating one to glance at.

Reading it

• How long until you can trust it? At a pound a week with daily weigh-ins, it takes about two weeks before the loss is clearly bigger than the noise. At half a pound a week it takes more like three.⁠[1] Don't judge a change to your eating by the first few days.
• Don't count week one. The first week of a cut includes a drop in water. Start comparing from week two.
• One odd week isn't a trend. Two or three in the same direction is.
• Compare it with your limit. If you're losing faster than your speed limit for more than a week or two, eat a little more. If you're well under it and you want to be done sooner, eat a little less.