For the last week of December, we’re re-posting some of our favorite posts from 2012. Cross-posted at The Huffington Post.

If you live in the U.S. you are absolutely bombarded with the idea that being overweight is bad for your health. This repetition leaves one with the idea that being overweight is the same thing as being unhealthy, something that is simply not true. In fact, people of all weights can be either healthy or unhealthy; overweight people (defined by BMI) may actually have a lower risk of premature death than “normal” weight people. Being fat is simply not the same thing as being unhealthy.

The Health At Every Size (HAES) movement attempts to interrupt the conflation of health and thinness by arguing that, instead of using one’s girth as an indicator of one’s health, we should be focusing on eating/exercising habits and more direct health measures (like blood pressure and cholesterol).

A recent study offered the HAES movement some interesting ammunition in this battle. The study recruited almost 12,000 people of varying BMIs and followed them for 170 months as they adopted healthier habits. Their conclusion? ” Healthy lifestyle habits are associated with a significant decrease in mortality regardless of baseline body mass index.”

Take a look. The “hazard ratio” refers to the risk of dying early, with 1 being the baseline. The “habits” along the bottom count how many healthy habits a person reported. The shaded bars represent people of different BMIs from “healthy weight” (18.5-24.9) to “overweight” (25-29.9), to “obese” (over 30).

The three bars on the far left show the relative risk of premature death for people with zero healthy habits. It suggests that being overweight increases that risk, and being obese much more so. The three bars on the far right show the relative risk for people with four healthy habits; the differential risk among them is essentially zero; for people with healthy habits, then, being fatter is not correlated with an increased relative risk of premature death. For everyone else in between, we more-or-less see the expected reduction in mortality risk given those two poles.

This data doesn’t refute the idea that fat matters. In fact, it shows clearly that thinness is protective if people are doing absolutely nothing to enhance their health. It also suggests, though, that healthy habits can make all the difference. Overweight and obese people can have the same mortality risk as “normal” weight people; therefore, we should reject the idea that fat people are “killing themselves” with their extra pounds. It’s simply not true.

h/t to BigFatBlog.