I don't know of any particular study, but if you don't eat a good balanced diet, taking vitamins is a good idea.
There HAVE been studies about vitamins, herbs, etc. related to memory - all have shown that there is NO "magic pill" which improves memory or concentration.
The best way to have a good memory is to be healthy (eat right, drink lots of water, get enough sleep, exercise) and use your brain! Try some of the related questions for memory tricks and tips, and do a mental "work out" by doing puzzles and brain teasers.
Taking vitamin supplements means ingestion of vitamins by means of medicines, and food with vitamins is vitamins in the natural foods like fruits and vegetabales. vitamin supplement is in vitamin deficiency.
Taking normal doses of vitamin C daily for long period is not likely to affect the kidney in any way. The normal dose of vitamin C, in scurvy is 50 mg of vitamin C, four times a day. But taking up to one gram of vitamin C per day for long term also is unlikely to have any adverse effects on the kidney.
Vitamin A deficiency can be prevented or treated by taking vitamin supplements or by getting injections of the vitamin.
Yes taking drug can interfere with memory.
Your stomach could be queasy after taking a vitamin for a number of reasons. You could have had it on an empty stomach.
There is no incompatibility between iron and vitamin C; some multivitamins contain both of these nutrients. Consult a physician before taking any nutritional supplements.
Vitamin A
Q10 vitamins have numerous benefits. However, if you want to research the specific benefits of this vitamin, you can find more information on WebMD. You could also speak to your doctor to determine if taking this vitamin would be beneficial for you.
You get sick, then your skin turns orange then you die. If your doctor tells you you are taking too much vitamin A, stop taking it.
Not necessarily. Men who take daily multi-vitamin supplements can have colored (yellow/orange) semen if the ejaculate within a few hours after taking the vitamins. If memory serves, it is ithe B vitamin that colors urine and/or semen. Consult a urologist.
With
It depends on which medication. One should avoid consuming excess vitamin E when taking the medication that is used for thinning blood. Too much consumption of Vitamin E is dangerous and you should consult a doctor before taking Vitamin E supplements.