I wouldn't say no signal at all. If I have data that they are the best doctor from my options and are obese, yeah totally, I'll go for them. But if I just see a lineup of doctors and all else is equal, I'm definitely picking the obese one last.

It's possible that they're obese due to some condition relatively out of their control, or that they're working on it, (and my answer applies specifically to the US) but when 40% of the US is obese, it more than likely reflects on them as a person and their values.