This is a common problem and certainly many people take supplements regularly. Unfortunately, the commercialization and relative lack of regulation in supplements means that companies can promote use even if there is no absolute clinical need.
Also, we cannot be sure what will happen with long term use as supplements rarely go through the rigorous safety checks that required from prescribed medications.
Often the best "supplements" are adequate rest, exercise and a good diet.
If you are concerned about specific symptoms, it might be worth attending a general check-up or going for a screening such as what we offer to athletes and the general public.
During this, you can discuss your concerns in more depth and specific blood tests can be organised to look for deficiencies - after which focused supplements can be provided.
Its always good to consult someone before taking things, often we don't need additional pills and portions other than the core elements I mentioned above.
Hope this helps.
BW
Dr Dinesh
