Fat does not make anyone gain weight. In the 50s and 60s, we had plenty of fat in our meals: fried chicken, beef and fish (which is surprisingly high in fat - although it is monounsaturated fat). Despite that, there were only maybe 2 kids in any grade I was ever in who would be considered "fat."
It has never been about fatty food: ever since people in the US adopted the "low fat" diet, they thought that gave them license to eat Oreo cookies, which had the nerve to advertise themselves as "low fat - 1 gram!" And people bought into it. And apparently still do.
The London Telegraph had an article about low-fat diets yesterday - oh, it's Sunday morning. Scratch that. It appeared in their newspaper on Friday.
It is astounding to think people haven't gotten the message that fat doesn't make you fat. The only reason for low fat is to be very "cut." If that's your thing, THEN you want low fat. Otherwise, there's no need for it. However, I wouldn't rush to eat foods cooked in lard, either.