Obesity has been linked to a seemingly endless array of negative health consequences (heart disease, diabetes, sleep apnea, and the like) but you might want to think twice before you judge a person's health by their weight, says another new study reported on the NYTimes Well blog this week.

Indeed, there’s a growing body of evidence suggesting that many of our attitudes about health and weight are misguided. While excess weight clearly is a risk factor for poor health, it doesn’t appear to be the most important issue. About half of overweight people and one-third of obese people have normal “good” cholesterol, blood pressure and other cardiovascular risk factors. And several studies show physical activity is a far more important predictor of health than body size is.

This isn't any free pass to eat tons of saturated fat or give up your gym pass, of course. If anything, it should be a wake-up call inactive people of all weights—including those that are slender. For help evaluating or re-envisioning your fitness routine (are you doing enough?), check out our latest guide to fitness, "Get Fit Now," for expert tips.