Here is my anecdotal case, so , FWIW
Myself and two kids started taking a daily fish oil pill about four years ago to help with ADHD issues and allergies from what I had been reading at the time
Since then we have all outgrown various allergies, me and boy to cats and daughter to milk. She was probably going to get past milk anyway because we were dealing with an allergist but it happened fast, like 6 months after daily regimen
Enough that we got a cat as a pet where I couldn't be in the same room as a cat before.
I can't comment on ADHD as its such a slow process and the kids were in grades where the points don't matter, however the boy seems to be doing well in school these days
Also, this time of year I used to get skin eczema on my hands and elbows now I hardly get it at all anymore.
Finally I work at a place that puts omega3 in seed crops via research. From the scientists perspectives when I talk to them they say, yes we don't get enough in our NA diet however we don't need as much as what is being promoted either. This is from the guys who read all the journals and articles regarding omega3 in our food systems.
So, one a day works for me and mine, and I feel that making it available is what is important and your body is best to moderate what is absorbed vs excreted