You know this person: that guy who can eat anything and everything he sees and not gain a pound. Your friend who hasn't been to the gym in years but wears a size 2. The individuals who have always had a svelte, naturally thin frame and don't seem to have to work for it at all. Turns out that the old adage "never judge a book by its cover" is applicable to your weight as well: because "skinny fat" is a huge issue, and it's largely ignored.

Doctors are saying that the biggest problem is that we, as a weight-obsessed society, put far too much importance on our weight. We all know that there's a difference between being thin and being toned, and we know that looking healthy on the outside doesn't necessarily mean we're healthy on the inside. But what we need to realize is that while obesity carries high risk of disease and cardiovascular issues, those who are 'skinny fat' might be at an even higher risk. Don't let your BMI and scale inform how healthy you are.

According to Time, "a 2014 report on people with 'normal weight obesity'-normal BMI, high body fat-found that they have a significantly higher risk of metabolic problems and death from these diseases than any other group."

So yes, you know that if you eat a lot of processed foods and excess sugar you're setting yourself up for danger. But while this kind of diet might not always make you go up a pant size, it does something worse: produces visceral fat. Different from its counterpart the highly visible subcutaneous fat, visceral fat will coat your organs. Because of its proximity to vital organs and virtual invisibility from the outside, it's far more dangerous and deadly.

It's all part of a misunderstanding of what being "fit" really means. Someone with a high amount of visceral fat but looks thin is at risk for the same problems and diseases as someone who is visibly obese: type 2 diabetes, high blood pressure, high cholesterol and unpredictable blood sugar levels. Heart disease is the leading cause of death in American women, so prevention and awareness of contributing factors is more important than ever.

Pretty terrifying stuff. This editor is guilty of joking "I know I'm thin, but my insides are probably a mess." Well now I know it's true: I rarely ever go to the gym, love sweets, could eat bagels for breakfast, lunch & dinner, and have never, ever had an issue with my weight. My friends say they "hate me" because I never gain weight, I'd just laugh and shrug. But they're not the ones who should be envious - they're the ones with good, healthy routines! I'm the one with some changes to make.

Read more over at Time.