I was 41 years old.

Around the same time, advance copies of my debut young adult novel were making their way out into the world. Because I had wanted to examine the toll of fatphobia, I wrote it in two timelines, following the same character, before and after a major weight loss.

The point was to tell teenagers that they were worthy of pursuing their dreams. But some readers just didn’t think it was O.K. to show a teenager, or anyone really, losing weight.

Many people in the body positivity movement — which I’d like to count myself a member of — believe that the desire to lose weight is never legitimate, because it is an expression of the psychological toll of fat shaming. So any public discussion of personal health or body size constitutes fat shaming. This recently prompted the founder of Greatist, a health and fitness site, to defensively write, “It’s O.K. to want to lose weight,” in response to criticism.

It’s worth noting that body positivity is the convergence of a few movements. The fat acceptance movement was pioneered in the 1960s by black and queer women to fight discrimination in public spaces, the workplace and doctors’ offices. Fat positivity, which is more of a reaction to fat shaming, and body positivity, which is a more commercial self-esteem movement, came later.

The problem with today’s version of body positivity is that it refuses to acknowledge that no one approach is right for every person. One teenager might grow up to be healthy at any weight, and another might end up in the hospital. It left my own daughter afraid to approach me about a topic on which I have both personal experience and expertise. It left me feeling that I couldn’t voice the rational concerns I have about diabetes.

I was the “wrong” kind of body positive because I’d been forced to admit that there could be serious health consequences to fatness.

I was the wrong kind of mother because I felt I should support my daughter’s weight-loss goals instead of talking her out of them.