I started taking about 10ug when I had really bad aches that were just getting worse.
My friend had researched it and decided that as you have to have at least 3 proper oily fish type meals a week, or the equivalent (not easy) and that making your own through your skin is not viable between Oct and Apr, then you need supplements during the winter.
So, I was a bit shocked to find that my levels were still well below optimum, at the beginning of winter, when you would have thought they would be ok after the summer. I would no doubt be deficient by now, if I had not taken the higher dose.
I was sceptical, but very surprised by how I felt suddenly better after 6 weeks. Now if I stop taking it, symptoms return.
You need to expose more skin than you think too. If we have a dull summer, we tend to be covered in scarves and cardigans.
I tend to keep well covered in the summer, because I burn easily. I also keep my tummy well covered as I had twins, and it looks a mess. I am getting a bikini and will be frightening the birds in the garden, during nice weather