I would say yes, but it is a crowded market. Think of all the sites that exist that promise great results fast. You're competing with all of them. My blog is aimed at health and politics, but also has a weight loss component to it, as well. I write about what is on my mind, not ranking, so the competition doesn't bother me. If you're interested in health, feel free to check out my blog.

http://thesoapboxblog.com