"I'm just worried about their health," you say to excuse anti-fat comments. To which I say: "Fuck you."
However fit your ass is, you are talking out it.
Health? Do you know what some people do to achieve and maintain a "healthy"-looking body? Taking diet pills and diuretics, vomiting after meals, starving themselves, smoking cigarettes to avoid weight gain, over-exercising, paying endless money for diet meals, or limiting their diet to the point of malnutrition, for starters.
But it isn't them you're judging when you nobly spout about health.