I’ve added all these to my diet and I’m pretty sure I’ve traced the onset of a stomach issue going back a week now to when I started taking them. I’ve taken fish oil with no issues in the past.
It’s a long shot, but the DMAE could also be an issue.
There are a number of neurotransmitters involved with running the digestive system (they’re not all used in the brain), and the increased choline could be knocking something out of balance.
But it’s a very long shot… serotonin levels generally screw with digestive behaviors more than anything.
What you probably should have done is stuck with the standard protocol with any stack of “add one at a time, use it for a few days, and monitor side effects, then add the next thing.”
In your case, drop the fish oil, see if it makes a difference. If not, add it back in, and drop the DMAE; if not, drop the B complex.