Every January, it seems the topics of weight and size come up over and over. New Year's resolutions to go to the gym, to eat differently, to lose weight. They're the kind of conversations that writer and podcast host Aubrey Gordon knows all too well, ones that she says are rooted in anti-fatness.

"Anti-fatness is a sort of web of beliefs, interpersonal practices, institutional policies that are designed to keep fat people on the margins," she told NPR.

Along with that bias comes a whole lot of myths about fat people, many of which Gordon debunks in her new book You Just Need To Lose Weight and 19 Other Myths About Fat People.

She talked to NPR about some of these myths, the many ways they affect fat people and the importance of the word "fat" as a neutral descriptor.

This interview has been edited for length and clarity.

Interview Highlights

On the myth that being fat is a choice

Some folks do choose fatness and some folks don't choose fatness. But researchers have been clear for years that our body size isn't solely or even primarily the result of our own choices. There are major contributing factors like genetics, environment, specific health conditions like polycystic ovarian syndrome and lymphedema – and social determinants of health. What kind of green spaces do you have in your neighborhood? What are your parents' income when you were born? What kind of neighborhood were you raised in? All of those have really powerful impacts on the size of our bodies, and none of those really have to do with our individual choices in adulthood.

On the myth of the Body Mass Index (BMI) as a reliable indicator of health

The BMI was not developed by a healthcare provider. It was developed by a mathematician, statistician and astronomer, and he was working exclusively with data from French and Scottish military conscripts in the 1800s. So we're talking about, exclusively, the bodies of white western European men from closer to 200 than 100 years ago, and we have continued to use that.

[The BMI] doesn't distinguish between fat or muscle or any of that stuff. And that's in white men. And its reliability goes down from there. So what researchers have found is that it may actually actively be harming the health of people of color and black folks and indigenous folks for whom it was never designed and was never tested or meaningfully adjusted for. It was also never designed, tested or adjusted for women. And it has become a major barrier to care, in particular for trans and non-binary folks seeking any kind of surgical care who will be told that they can come back for surgery when they've reached a certain, usually relatively arbitrary BMI level. For fat people like me, what that means is that doctors offices will code most of our visits as "obesity interventions," and that we will, in some cases, be denied even routine surgical care because our BMIs exceed what doctors offices are expecting. So this is really sort of a deeply, deeply imperfect tool that we are using, not for the thing that it was designed for, which was population level analysis.

On the myth of the "average" body and the way it affects our environments, like blood pressure cuffs

It's worth reminding ourselves in these conversations that in the United States, the average is plus size. The average person is a fat person. So we are building environments that are hostile, not only to some vanishingly small minority of people, but to most of us.

Most doctor's offices carry cylindrical blood pressure cuffs, which are designed for measuring thin people's blood pressure. There are also conical blood pressure cuffs that are designed to fit fatter arms. Thin people can use those conical blood pressure cuffs without instance, but when fat people try and use the ones designed for thin people, it gives us artificially high blood pressure readings. So when we talk about the health risks of fatness, we don't talk about very simple mechanical things like that, that might actually be giving us numbers that are not super reliable because we're using tools that are not designed to measure fat folks' health.

On the importance and impact of saying and hearing the word fat in a neutral way

I was at a women's soccer game – I'm a huge women's soccer fan – with a friend of mine, and I was looking at their merchandise and was flipping through the racks. And they didn't have an offering in plus sizes that would fit me, and my friend was like, "You should get a T-shirt." And I was like, "no, they don't have fat lady sizes." And a stranger turned around in that little merchandise store and went, "don't call yourself that, that's terrible. You're not." And I thought, well, I'm a size 26. I weigh over 300 pounds. I don't know where your standard is for fat people, but I'm pretty sure I'm in it by most people's standards. But it is this very strange moment where, when I say that, other people and usually thinner people rush to object to that. They're not disputing that my body is actually small. They're shadowboxing with their own assumptions about what it means to be a fat person. They're assuming that what I'm saying is that I'm unlovable, that I'm undesirable, that I'm ugly, that I'm rejected, that I'm unlikeable, all of these sorts of things. And while they think they are defending me, what ends up happening is that they don't end up listening to me. And this becomes a place where thin people start to name fat people's experiences and bodies for us without really realizing how wild that is to tell someone else how to feel about their own body and how to describe it.

The more comfortable that people, particularly people who are not fat, can get with hearing the word fat, the more they'll be able to actually hear out actual fat people's experiences. And I think the other thing that it does is it requires folks to face their own biases and what they've attached to the word fat so that they're not going around and projecting those assumptions or that sort of emotional baggage onto fat people who are mostly just trying to live our lives.

On moving away from saying things like "I feel fat"

Fat is not an emotion, fat is a body type. And fat people's bodies are not metaphors for thin people's low self esteem or bad body image days. It is really disheartening that when people want to talk about feeling at their worst in their bodies, the descriptor that they reach for is a descriptor of my body. They're saying, "I feel terrible today, which means I feel like I look like you," which feels terrible to me. It leads us pretty directly into treating fat people differently and worse when we collapse our ideas of low self esteem or bad body image into the idea that that means feeling fat.

Audio story produced by Kat Lonsdorf

Audio story edited by Sarah Handel