Could this be the real reason you have trouble losing weight or saving money?

Struggling to lose weight or build up your savings? Here’s a new insight that might really help.  If you are like most people, you tend to remember the good days — when you eat salads or don’t spend –better than the bad days, when you lose the battle with the cookie jar, or Amazon’s 1-click.  It’s a little bit like a behavioral habit called “optimism bias,” which we wrote about in The Plateau Effect, but this particularly insidious form is called “progress bias.” It could be a blind spot that’s really be holding you back. I wrote about the phenomenon recently for CNBC.com.  Here’s a tease, and a link.

You’ve been good all week, so what’s the harm of having a donut for breakfast on Friday? Or splurging on those new shoes? It could be the reason your bank account is empty but your belly is, ahem, a little full. Particularly if you forget that Tuesday happy hour …..oh, and that birthday cake on Wednesday… when you’re picking out your Krispy Kreme.

There’s no harm in splurging once in a while, of course. The harm comes when we forget what we’ve splurged on, but we remember each and every donut we didn’t eat. New research suggests we fallible humans often give ourselves outsize credit for all those moments of denial, but fail to properly weight the failures.

It’s a phenomenon that’s been labeled “progress bias” by University of Colorado researcher Margaret Campbell in a new paper published in the Journal of Consumer Research called “When One Step Forward Seems Larger Than One Step Back.” Campbell ran a series of tests and found that people exaggerate the impact of their good choices and let mistakes slip their minds.

In one simple experiment, Campbell and fellow author Caleb Warren of Texas A&M measured people’s reactions to either saving $45 or spending it. The savers credited themselves with 20 percent more progress than the spenders debited their mental accounts.

In a world where investors are fighting for every 1 percent they can find, understanding progress bias could make an enormous difference. You can’t build up your savings by spending wisely 29 days each month, then blowing your budget on the 30th day—even if that feels like progress.

What’s the antidote to progress bias?  Honest assessment and measurement, for one. This is one place where spending or health apps can really help.  For more on solutions, click to CNBC.com.

Read the rest of this story on CNBC.com

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