2 niches?

Are there successful business structures where people have 2 separate niches? Do they put them on the same website? I would like to focus on healthcare providers AND young women (high school and college-aged). I have extensive experience with both. I think of Brooke having the Stop Overdrinking niche and the Stop Overeating niche and its seems possible, but then I feel they are also related. So, I am not sure if it works having two different age groups vs two different topics. Thank in advance! (PS I didn’t go into the specifics of the niches yet because I wanted to just know if having 2 was a good idea or not;)