Antagonism of perception practical and aesthetic

"If you were thiner, you won't exist!"
Am i really ill at this point?, the persons who surround me seems to have different pragmatic and aesthetic criteria than myself; the fat for the animals is useful to survive during compelling fasting periods du to a lack of food or hibernation, but for humans, also part of the Nature, in this times of abundance of provisions, it is practically useless to have a layer of fat on the body, this only exhaust us and slow us, we become less enduring, less athletic, less dynamic when we are overweight, therefore it is rightfully and for the entirely practical part that i'm glad to be thin, a thiness which i don't cultivate, my body represent my way of life and my personality, i need to be lively and passionate, to spend energy, to move freely, my body adapt himself and is the image of my way of living;
So, are all these criticisms due to jealousy?! because thinness is for sociéties a characteristic of beauty, but particularly for women, so being a man am i really perceived as "ill" like in having a sickly body, being too thin; does the perception of people around me could be correct, honnest?! and am i really slender though i don't see it?! or their gibes are only jealousy to confort them in their own bodies, or this is simply a difference of views aesthetic and practical?!; anyway, their remarks annoy me because the fact i was thin was the only point i tolerated in my appearance.

(i know this photo is obscene, but it illustrates prefectly this post, a friend of mine took it by himself without request probably an attempt to prove me i am too thin)