Data Driven Weight Management

How to manage your weight the fun and easy way – with a spreadsheet

Here is the method that I and others have found to be the most effective for managing your weight, whether you want to lose, maintain or even gain weight. It is a very simple method, but if it fits with your particular mindset and psychology then it works very well. Particularly if you know what is a healthy diet and if you’ve tried calorie counting or other diets in the past.

Weigh yourself every day, and use a spreadsheet to record that weight.

That’s it.

This method takes inspiration from the “Lean Analytics” movement, and in particular the notion of “One Metric that Matters”. If your goal is to lose weight, then weight is the metric that matters and that is what you need to track. Important to acknowledge here that weight is not a perfect indicator of physical health, or athletic performance or attractiveness – but as a metric it has some features that make it very useful:

  1. You can measure it easily and precisely. Buy some bathroom scales, stand on them and write down the number. It takes 5 seconds. Compare this to testing your 5km time, or trying to measure bodyparts or compare photographs.
  2. Because it is so easy to measure, you can do it every day. This gives you instant feedback on the consequences of your actions. You know that eating cheeseburgers and cake will have a negative impact on your progress, but now you will see that immediately, or at least in a day or two. Vice-versa, 2 days of disciplined actions will result in a measurable change in your weight (assuming digital scales in kilograms)

You may say that you don’t actually want to lose weight. What you really want to do is to look better naked, or be able to run quicker or some other underlying goal, so you should be using a mirror or a stopwatch to measure your progress. What I say to this is that you can worry more about that other stuff, once you have your weight in the right area. In my case that means getting down to a healthy BMI. In other people’s case, it’s about getting back to their pre-baby weight.

This method can be intimidating, as it forces you to face the consequences of your actions, but you should realise that this is a good thing. If you find yourself not wanting to record a weight after a particularly heavy weekend, then you should ask yourself how serious you really are about achieving your goal.

The spreadsheet template will calculate a weighted 10-day average weight, which smooths out some of the natural ups and downs you will experience. Given a target weight, it will calculate when you can expect to hit that target, based on your progress so far. It will also show how consistent you have been in your weight loss (or gain) and the change in the last 7 days.

Here’s the spreadsheet

This is what the spreadsheet looks like

This is a Google spreadsheet and is locked for editing – to use it you’ll need to make a copy of the template you can use. Otherwise you’d be over-writing the template and I would be able to see everything you’re doing. If you have a Google account then sign in to that, make a copy of the template to your own Google Drive and crack on (File >> Make a Copy). If you don’t have a Google account then I recommend getting one just to use Google Drive, but otherwise you can download the template to use in Excel. I have not tested the template in Excel, and recommend using a Google account and Google Sheets. The Google Sheets app for mobile is good and easy to use as well.

You start by entering your target weight in cell G1, in this case my target is 91.0. You also need to enter the date you are starting the plan in cell B6. Then every day you enter your weight in column C and everything else will update automatically. You may want to enter notes in column F to record any reasons for why your daily weight moves.

There’s also a tab with a chart:

My progress is pretty erratic. Christmas was not a good time for the diet

The red line here is the weighted 10-day trend which you can see smooths out a lot of the day-to-day variation and is the line to worry about. In my case I started really well, then went on a work trip to Italy which set me back considerably. Summer I made much slower progress but still progress and now I’m going to have to work off everything I’ve put on over Christmas. I’m confident I’ll get to my target though. Here is the equivalent chart of someone more disciplined than me:

You can’t expect to lose weight at Christmas

I am not a doctor and have no training in nutrition or dietary science, you should eat a balanced diet with lots of vegetables and exercise. But if you are not at a healthy weight, then this is the most effective tool I have found to game your psychology into getting you to a healthy weight. Use at your own risk