True story: I am on a diet right now. Since September, I've lost about 40 pounds and am currently barreling my way to a size medium. I'm feeling pretty great. But, when I started, my partner said he'd change his habits with me and he hasn't had nearly as much success (SRY FOR THE CALL OUT). Why? Because, according to a new study, dieting together actually decreases confidence.

It makes very little sense on the surface. Your partner, whom you love and adore, wants to make some changes with you (in order to promote their own well-being as well yours) but if the results of 50 couples who tried to diet together is any indication, dieting together actually makes everything worse. Could it be that both partners are just lousy at motivating each other or deciding not to eat junk food? (My partner and I've tried dieting together before, but our mutual weakness for burritos ruined us) Or could it be, as this paper suggests, that as one partner becomes successful the other loses confidence?

From The Science of Relationships:

We also found that among 50 overweight, romantic couples who made New Year's resolutions to lose weight, the more successful a partner was at restricting his or her diet and eating healthier, the less confident the other partner was in controlling their own food portions. Why might this be the case? Many factors contribute to why people deviate from their weight-loss goals, and the ability to regulate portion sizes is a critical piece for solving the weight-loss puzzle. When people strive to reach a goal, being close (in this case, romantically) with someone who is successfully reaching the same goal can make the other partner less confident in their own efforts to reach the goal. You heard that right: People feel less confident achieving their goals when they see others succeeding at the same goals.

It sucks, but I can see it. Dieting is already such a tedious and unpleasant process fraught with disappointment and excuses — for a long time I just thought I couldn't physically lose weight — that watching someone you love succeed can be painful even though it shouldn't be (logically) and therefore it's easier to give up and say "I didn't even try" than to try and not do as well. But it could also be due to the fact that change is difficult. For instance, having quinoa for breakfast and realizing that this is what life is going to be like from now on? That's going to cut a little confidence as well.

The reminder here, of course, as author Jennifer Jill Harman points out is that when you're making a change you shouldn't compare yourself to others. We all lose weight differently. Some of us can diet and diet and lose two pounds in three weeks, and some of us (Like Irving in the Cathy comics) can skip lunch and lose fifteen pounds. That's why if you're going to diet, it shouldn't be a competition. Unless the diet is "how many pizzas can you eat in one day?" There's no way in hell I'm losing that.

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