1. It added another barrier between me and spending money
It's easy to mindlessly swipe a credit card and forget you even bought something. Try handing over physical bills and watching your money disappear right in front of your eyes. Chances are, you'll start to think longer and harder before making purchases.
On the cash diet, I became a much more conscious spender, buying more of what I needed and less of what I wanted.
2. I was more in tune with exactly how much I was spending
In general, I'm pretty good with knowing about how much money I'm spending, as I keep track of my daily purchases in an Excel spreadsheet. But on the cash diet, I always knew exactly how much I had remaining in my budget — I simply opened my wallet and counted my bills.
It was also eye-opening to see how quickly cash can disappear with what I always imagined were small, insignificant purchases. A few short cab rides and I'd blown half my budget.
3. It forced me to stay on budget
I've always had a target number for how much I want to spend each week, but often, it's just that: A number that I hope to stick to. The temptation to spend, especially in a city like New York, coupled with unexpected expenses, makes it all too easy to go over.
The cash diet turned that abstract target number into something tangible: Physical cash that I could actually see and hold. It made my budget real in a new way. After all, once my wallet was empty, I was done spending for the week.