I take a lot of vitamin and other supplements. I think the science is clear that taking such supplements can help keep one healthy and can extend one's life expectancy.
I also know there are a ton of charlatans out there making promises that can't possibly be kept. Separating the wheat from the chaff requires careful weighing of the evidence.
I find Life Extension Foundation to be a consistently reliable source of information on the latest scientific findings on the usefulness of vitamins and supplements and an excellent source of those supplements. They sell pharmaceutical grade supplements and I believe you get exactly what you order. They also publish a great monthly magazine with the latest findings on efforts to extend life expectancy and keep one healthy as long as possible. A visit to their website will give you a taste of the vast stores of knowledge this foundation has. I highly recommend their products and have every confidence that their supplements are of the highest quality. Use your brain. Join LEF and get their vitamins and supplements.