Depends on what it's for and what you're goals are. I'd suggest being prudent as toxicity can be a concern.
Have you considered eating liver or sweet potato? Again, without knowing circumstances of why you want to supplement etc it's difficult to say what you 'should' do...
Here, near Toronto, I've been taking Carlson (lemon flavoured) fishoil every winter, but now I'm re-thinking everything. I read some older stuff on PH re fish oil/cod liver oil and am looking forward to reading new comments too.
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