You have to go pretty far for that to be a problem.

I'm 5'9.5" which I round to 5'10", eat just enough to avoid being hungry a half hour after my last bite every time I get hungry with fewer carbs than I used to eat, and was worried when I reached 145 pounds and was still shrinking to less than typical adult size.

Ribs and sternum poking out scared my wife.

So I asked my endocrinologist about my condition. He said it was "great."

I started adding extra food to stick around 137 - oblique vascularity is good; ab vascularity a bit extreme for me although I didn't notice any health problems.

I was a little lighter and less lean after a training break following a crash when I went in for my annual checkup. I asked my doctor about my weight. She said it was "great" although she wouldn't tell me to loose more, asked whether I'd read the longevity studies, and showed me the BMI calculator which has me comfortably in the green zone.