The problem is that with populations moving with the ease that they do nowadays, you get people with very dark skin that is suited to the amount of sunlight that you get at the equator, living in Birmingham where there isn't very much sunlight at all.
Tiktok, my father was concerned enough about the inability to get enough sunlight in London for me and my children (we are all fairly pale), that despite our spending a fair amount of time outdoors, he insisted that we all take multivitamins. In fact, I now live in Los Angeles and my father still wants us to take multivitamins, just to be sure. He is currently working on a paper that will recommend that that the daily requirement of Vitamin D is increased substantially.
Whomovedmychocolate...it's actually the other way around. Calcium generally has Vit D bundled with it, because you need the Vit D to be able to utilize the calcium. It's easy to find multivitamins with Vit D and without Calcium (which is what I take because the calcium constipates me).
NoviceKnitter, my understanding is that you need to start giving vitamin supplements at 6 months because that is when you should in theory begin weaning from breastmilk and since the baby will not be eating a fully rounded diet for another 6 months or so, yet will not be getting full dose of breastmilk with all its nutrients, it's a good idea to supplement with vitamins. Again, that's what my father recommended I do.
There is a school of thought that thinks that you should be able to get whatever you need from diet and lifestyle alone. And there is some validity to this theory. However, I trust my father and think that his belief that taking multivitamins is a good idea. Especially since there doesn't seem to be any downside in taking "too much" of most vitamins. The ones that do have adverse effects if you overdose on them are generally present in limited amounts in the average multivitamin.
In order to remember to take the vitamins, I give my kids theirs with breakfast and I take mine at night with my birth control pill. Try to find something in your daily routine that you never forget to do and put your vitamins next to it (ie brushing your teeth, doing dishes, etc.).