Its the hub on cholesterol lowering foods, right? Thats what I guessed when you first posted this. Id guess the traffic surge is because the hub is titled in a way that many people are likely to google the topic.
I googled 'fish lowers cholesterol' and your hub is on the second page. (Congratulations)
You want to title your hubs in a way that people are likely to search on the topic (like that one is). "Cholesterol lowering foods" is a very google friendly phrase (though id guess there are a lot of results to compete with there..)
If your other hubs are just meant to be read by the hubpages community, the titles aren't so important. But if you want them to draw in search engine traffic, title them the way you yourself would search for the same info.