I tried the green pastures fermented Cod liver oil and had a migraine the next day. I was too chicken to try it again so have it to my mum who has been ok with it. I have gone back to the lemon flavoured Nutra pro Cod Liver Oil (which I have been able to use before) and landed a headache most of the next day! I had suggested my daughter try the GP fermented oil and she has been getting headaches too (3 times tried). I do have (suspected) Histamine intolerance which i believe may fluctuate. I’m wondering if this could be the cause? I know fermented CLO is considered high histamine, I thought regular CLO would be ok because I have tolerated it before but it may be borderline? It’s interesting that the CLO myself and the original poster took was lemon flavoured- not sure if that is a red herring (ha ha). Interested in other experiences Vanessa