Once a month, stop for a moment, look back and count the days you'd call good. That's the whole method.
I made this one up, and I'd rather say so. Biohacking is about measuring things, so I thought, why not measure good days too? It isn't a science-based metric like heart rate variability. It's amateur psychology. It's also the simplest measurement in my book, and you don't need a device for it.
The book is called More Good Years, and a good year is made of good days. If you want to know whether your life is getting better, you could do worse than count them.
What counts as a good day
That's up to you. Here's mine.
I wake up feeling energised and I go to the gym. If my data says I can, I go into my ice bath. I feel clear-headed. I'm present at work, I can contribute to my meetings in a constructive way, and I don't get unnecessarily irritated. When I do, I don't blame myself for it. I end the working day feeling fulfilled, because I did what I wanted to do. Then a relaxing evening with a nice conversation with my wife. When I meditate and think back over the day, I can feel grateful for what's there, and I sleep well.
Your list will look different. Maybe there's no gym in it and no meditation at all. Write down what's in yours, because you can't count something you haven't defined.
It doesn't have to go to plan
Take one Monday not long ago. I'd played a golf match on the Sunday and it was slow: five hours, everybody concentrating, a lot of waiting between shots. That exhausts me. After fourteen holes I'd had enough, and by the evening I was tired.
On Monday morning, for the first time in about a year, I didn't want to go to the gym. So I didn't go. You could call that a bad start, because I broke my routine. I'd listened to my body, though, and it's human to be tired the day after something like that. It was still a perfect day.
The same goes for the meeting that didn't go to plan, or the brain fog that cleared up by mid-morning. One bad hour doesn't have to cost you the day.
Why bother counting
When people look back on a crazy week, a lot of them look at the bad days first. Maybe there were only one or two, yet they say, "This was a tough week." Even with two bad days, that's five good ones.
Psychologists have written about this tendency for a long time. A well-known review is called Bad Is Stronger Than Good, and it argues that bad events tend to weigh more heavily on us than good ones. That fits what I see. I don't know of any study that tests a monthly count like mine, so I can't tell you it will do anything measurable for you. I only assume that most people have more good days than they think, and that seeing them changes how you look at your life.
The other reason is plain awareness. Most people rush through their days, always thinking about the next thing. For some, it takes real effort to remember what they did the day before yesterday. A count makes you stand still.
Good days in a bad year
This isn't a way of pretending everything is fine. I learned that during the years I was ill after a bad reaction to a malaria drug.
Even then I had good days. There'd be a day that was perfectly organised, with one or two meetings instead of a full diary, nice weather and everybody relaxed. I could sit in a meeting, enjoy it, contribute something and laugh. It confused people. They'd think, what's wrong with this guy? He's sitting there laughing, so why can't he just work eight hours? They couldn't see how much it consumed me despite the smile on my face.
Both things were true. Those were bad years, and they still had good days in them. I'd want to know about both.
Where it fits with everything else
I work with five dials: sleep, nutrition, movement, mind and connection. A good day is a combination of all of them, so the count sits above the five and doesn't belong to any one of them. Wearables can tell you about your sleep and your heart rate. They can't tell you whether it was a good day.
Three things you can do today
Write down your good day. A few lines are enough. Use your own words and leave out anything you think should be there but don't care about.
Set a reminder for the end of the month. Look back through the month and count the days you'd call good. Once a month is enough, so don't turn this into a daily score.
Keep the number somewhere. One number means little. After a few months you can see which way it's going, and what the better months had in common.
A count can't replace help. If most of your days have felt bad for weeks, or you've lost interest in things you used to enjoy, talk to your doctor or someone you trust. If you ever feel you can't go on, contact a crisis line or emergency services right away.
Good days run through my book, More Good Years. Find out more.
Eduard de Wilde has tracked and tested his own biology since 2008. He founded NoordCode and Livehelfi, co-founded the Syntony Institute, and wrote More Good Years. He isn't a doctor, and he sells some of the products discussed in this field. This article is for information and isn't medical advice.

