2 formerly obese economists lost a combined 120 pounds in 18 months - here are the best tricks they used

Rob before after

Courtesy of Simon and Schuster

If you're looking to shed pounds, look no further than an economics textbook. Rob Barnett is pictured before and after losing weight.

  • Christopher Payne and Rob Barnett are economists and the authors of "The Economists' Diet." They both were once obese.
  • Payne and Barnett say the behaviors that affect weight can all be explained by the principles of economics.
  • Those principles include: minimize decision-making, stick to a boring diet, and weigh yourself every day.

Rob Barnett calls it the "fateful conversation."

He'd just appeared on a video for Bloomberg, where he worked as an economist, discussing a recent news event.
Barnett asked a fellow Bloomberg economist, Christopher Payne: "Did you see my latest video?"

"Yeah, I saw it," Payne said. "Good job."

"Thanks," Barnett responded. "But f-k, man! I'm getting fat."

Payne didn't beat around the bush. "One could say that," he told Barnett. "One could also say that you are fat."

Barnett and Payne reproduce this conversation in their new book, "The Economist's Diet: The Surprising Formula for Losing Weight and Keeping It Off."At the time of the fateful conversation, Barnett was severely obese. Payne could identify - at one point in his life, he'd been obese, too. Then he lost about 45 pounds in 18 months.

The authors say the exchange that followed helped them both realize that the behaviors that affect weight can all be explained by the principles of economics. Barnett eventually went on to lose 75 pounds, also in 18 months.

The book is an outgrowth of that original conversation: The authors teach readers how to approach weight loss the same way they did. I recently spoke with the authors over the phone about the weight-loss strategies I found most compelling. Here's what I learned:

Use meta-rules to minimize the chance of making bad choices

Use meta-rules to minimize the chance of making bad choices

A meta-rule is a guideline you set in advance that covers all situations. The authors say they borrowed the term from Duke University behavioral economist Dan Ariely.

An example of a meta-rule is: "Unless it's a special occasion, I never have seconds" or "During the week, I always have salad for lunch."

The idea behind meta-rules is that you're eliminating as much choice as possible. "The more times you present yourself with a choice, the more possibility there is to do something that you're trying not to do," Payne said.

Use meta-rules to save yourself some mental energy

Use meta-rules to save yourself some mental energy

Using meta-rules is also less mentally exhausting. Payne said that if you're trying to lose weight, it's best to just not have cookies (or whatever you're trying to avoid eating) in your home. Otherwise, you'll have to make a decision every night about whether to indulge.

Barnett and Payne are hardly the only people to minimize decision-making as a way to achieve a health goal.

Max Levchin, a cofounder of PayPal and the CEO of online lending service Affirm, previously told Business Insider's Alyson Shontell about the importance of consistency in his fitness regimen.

Levchin said: "So long as your daily default is 'Be on the bike,' some days you'll miss because you're traveling or you're sick. But most of the time, you'll just get up, and get on a bike first thing in the morning, which is what I do."


Stick with a boring diet

Stick with a boring diet

"A boring diet is a slimming diet," Barnett said.

It goes back to the concept of diminishing returns. To use Barnett's example, if you eat a single Oreo, you're going to really enjoy it. "If you eat a full bag of Oreos, by the time you eat the last one, you're not going to get nearly as much happiness or utility out of it."

He added: "If you restrict your food choices day in and day out, no matter what kind of preferences you have for food, you're going to get bored with it."

Both Barnett and Payne said they eat a salad for lunch every weekday. ("I've gotten to like salads over the years, but I don't have the urge to overeat a salad," Payne said.) When Payne goes to Starbucks, he orders an Americano with a dash of nonfat milk.

What's more, when you do allow yourself to splurge, depending on your specific meta-rules, you'll enjoy it that much more.

Weigh yourself every day to keep the numerical goal in mind

Weigh yourself every day to keep the numerical goal in mind

This weight-loss strategy is more controversial than the others. But the authors say it's worked for them.

A 2015 study by Carly R. Pacanowski and David A. Levitsky, published in the Journal of Obesity, found that overweight men who weighed themselves every day and received visual feedback about their weight trajectories lost more weight than their counterparts who didn't weigh themselves as frequently. They were also better able to maintain the weight loss.

Another study, published 2017 in the International Journal of Obesity, yielded similar findings in women.

Other experts advise against weighing yourself every day. For example, Moran Cerf, a professor of business and neuroscience at Northwestern University who has been studying decision-making for over a decade, told Business Insider's Chris Weller that people should weigh themselves just once a week.

One dietitian told USA Today that she doesn't recommend daily weigh-ins for most clients: "You can get lost in those numbers and start to identify your self-worth with what's on the scale."


Weigh yourself every day — and stop tracking everything else

Weigh yourself every day — and stop tracking everything else

Still, Barnett and Payne call weight loss an "empirical process." Payne said, "You're basically a scientist of your own body." That is to say, you weigh yourself in the morning, see whether the number's gone up or down, reflect on what you ate the day before, and tweak as necessary.

Interestingly, the authors don't recommend tracking anything but your weight. Barnett argued that if your weight is the piece you're trying to control, that's the only thing you should keep tabs on — not, for example, how many steps you take.

Barnett put it in very frank terms: "Your obesity — or lack thereof — it's not a secret to anyone. You should get acquainted with that number. … It really is a life-changing thing to add this to your daily routine."