If I am taking a fish oil supplement with total omega 3 fatty acids (EPA and DHA) of 300mg, is there really any benefit of picking up a bottle of just DHA? I think 300mg is probably not enough (I weigh 174lbs.) but is it better to take fish oil with EPA/DHA or is it better to also have a pure omega 3 fatty acid supplement?
Your question is a bit confusing. There are multiple forms of omega 3s. Some of the more common forms are EPA, DHA, and Alpha Linolic Acid which is most common in flax. EPA and DHA are higher forms of omega 3s than the type in flax; with DHA being the highest form. The omegas from flax have to be converted up to EPA and DHA in the body, a pretty inefficient process from what I've read.
I don't understand what you mean by a pure omega 3 fatty acid supplement. I'd say that your fish oil is kind of low in omegas (180epa, 120dha; I'm assuming,) as there are many that are close to double that dosage per softgel.
Or you can go balls out and get liquid fish oil and get even more omegas per serving.
Benefit to just DHA, sure. DHA available in higher amounts is usually targeted for mental/mood support. Usually the higher DHA products have lower EPA, which has it's own array of health benefits. I like em both.