h1 tags will certainly not help your SEO, as they should be used to indicate the header for the page, as covered here: Matt Cutts - More than one H1 on a page: good or bad?
If there are 10 different topics on the same page, you could pick the top one for the
h1 tag, and then stylize the other topics using CSS so they visually look like headers...
Instead however, you might consider adding separate pages for each topic with links and anchor text for them. That way, each page will be better focused on specific topics and keywords, which will be clearer to visitors so that they can decide which to view, rather than being overwhelmed with ten different topics that might result in higher bounce rates.
That will also provide additional internal links that can be indexed by search engines and provided in your SERP.