The key to successfully introducing your oil product is to understand – and articulate – your product’s Unique Selling Proposition (USP).  In other words, what is it specifically that makes your product superior to existing omega-3 oils?  By overwhelming the reader/prospect with a strong case for what makes your product superior, you’ll be off to a great start.
One other point – when it comes to those things you may perceive as a negative (higher price, established/competitive market, unknown product), I’d argue that you should use flip those points around and turn them into positives.  If your product is priced at a premium compared to others, use that opportunity to explain how individuals could actually be throwing their money away by buying an inferior product.  If the marketplace is competitive, explain to the prospect how fierce competition may lead suppliers to cut corners, resulting in a less-potent product for the user.  And if your product is unknown – take every opportunity to spell out what makes it unique.  Is the formulation different?  If so, why?  What is it about your product that not only justifies its space in the crowded market but makes it far superior to the others?