There are several variables about fish oil you need to know.
The first major hint that something of therapeutic value existed in fish oil was an enormous study by the AMA of Doctors and Nurses, which discovered that those who ate fish once a week were much less likely to have the acute, fatal type of heart attack when you are dead before you hit the floor.
The next major breakthrough was in discovering that the Omega-3 oil was the responsible factor. It had anti-inflammatory properties that balanced out the much more common Omega-6 oil, found in other meats, which by itself could slightly inflame tissue. (There is also the healthy type Omega-9 oil, but it is much less potent.)
And now it has been discovered that healthy Omega-3 oil actually has two components, EPA and DHA, and DHA does most of the “healthy heavy lifting”. So now just DHA is sold in stores as such.
(Importantly, do not confuse DHA with another OTC supplement called DHEA, which is completely different.)
EPA is still good, so fish oil is still good, but if you want to “cut to the chase”, you will want just DHA, and few fish oil pills once a week.
Proving that Catholics are goodhearted.
Also, you need about 600 mg of Omega-3 a day. It’s not necessary to take Omega-6 because we get that from multiple food sources already. You’re supposed to get twice as much Omega-3 as Omega-6. Omega-3 is linked to brain development, so it’s important for pregnant women to add it to their supplements.