With Vitamins it is a little bit like the paragraphs above.
If you are fit in general and you want to take some vitamins: fine.
If you are not fit, please go to the doctor!
If you want to do something good, watch out for Vitamins A + C + E.
They are the ones in richly coloured foods, i.e. peppers, carrots etc.
Again, if you have good enough health and you have a somewhat balanced diet, then take vitamins if you think they help you.
If you are not healthy and/or have a very ‘unusual’ diet, please seek advice.