You hear lots of sad stories about terribly underweight people who think they're fat. You also hear stories about obese people who think they're normal, and stories about normal people who just don't like their bodies in general. So, it's really no surprise that a slew of studies show most people are bad at gauging their own size. In fact, most people underestimate their body weight and its implications quite drastically.
According to one recent study, quoted in today's Times:
People in the normal weight range selected the correct category about 80 percent of the time, but 58 percent of overweight students incorrectly described themselves as normal weight. Among the obese, 75 percent placed themselves in the overweight category, and only 10 percent accurately described their body size. (Notably, a sizable minority who were at a healthy weight described themselves as being underweight.)
So, are most people just in denial about weight gain, or is there something about our brain chemistry that prevents us from noticing? The Times points out that it's mostly the latter:
While researchers admit that some denial may have to do with personal embarrassment, the consistency of the findings suggests that neural processing and psychology probably both play a role. It is also possible that a few extra pounds isn’t an urgent priority for the brain to acknowledge. Researchers at University of Texas Medical Branch in Galveston found that one in three women did not know when they had gained 5 pounds, and about 15 percent weren’t aware when they had gained more than 10.
It's an interesting dichotomy: On the one hand, studies show that people — particularly female adolescents — are strongly affected by advertising and other environmental factors when it comes to their body image; on the other hand, it now appears that most people are blissfully oblivious to their own weight gain. How strange that the ability to gauge one's own size isn't naturally wired into the brain as much as we might have thought (or hoped). Do any of us actually know what our bodies really look like, since what we see in the mirror is some flawed conglomeration of our what we hope to see, hate to see, and actually see?