Also, mild or moderate anaemia is pretty common, but people don't realise it.
Just make a note of the days when you feel listless, crappy, lethargic or can't concentrate. If it's often, you MIGHT be mildly deficient in something.
Ideally, we should all be eating lots of fresh fruit and veg, pulses, meat etc, and we should try to do that, but often we fall short. I think that the levels in multivitaims are low enough to not cause a problem if you have a both a good diet AND take a pill.
if we added Vit D to biscuits we could solve this problem
They add it to milk in the northern states of the USA, and they are further south than we are.