I like seeing videos about working out on Youtube because I'd like to learn tips from people who work out. Whether it's running, losing weight, going on a vegan diet (which I'm not doing btw), etc, you can find some great tips from people who are actually doing those things. And it's a lot better than listening to somebody ramble on about how you need to eat more salads and that person isn't even losing weight.
Do Twitter and Instagram put me down about body image? No. It makes me feel better because I know,unlike many of them, I have a personality and I don't have to rely on taking pictures of myself to get people to like me.