too many vitamins are actually bad for you
No. I literally just watched a documentary about this. There is no proof at all that too many vitamins are bad for you. The worst they can do is give you temporary side effects such as diarrhea or headaches. For example, there was a women suffering from severe depression, all she'd do was sit in the corner all day. A nutritionist suggested giving the women increasing amounts of Vitamin C until she felt better. Once they had increased the amount of Vitamin C to 11,500 mg a day, she was no longer experiencing the depression. However, as soon as they stopped with the Vitamin C, she was back in the corner.
Statistically, there have been only ten deaths in the past 24 years or so that were only suspected to be caused by overdosing on vitamins. And that's left to suspicion. Compare that to the number of people who did each year due to overdosing on manmade drugs.
There are other things super-dosing on vitamins can do as well. By increasing one patient's intake of Vitamin C to 200,000 mg per day (at a nutritional clinic, not a hospital, mind you), the patient was effectively free of the cancer they'd had previously. There are many other similar success cases from nutritional clinics as well, but why don't we hear about them? Well, for starters, nutrition is hardly even touched upon in med school, so most doctors aren't even aware as to the effectiveness of vitamins. There's also the major drug companies' involvement, absolutely bombarding the market and society with the promise for "drugs for every ailment". This puts the spotlight on them, partially on purpose. After all, if the world knew just how effective vitamins could be, drug companies would rapidly lose money. They make up a huge portion of the country's GDP, so that would cause an economics uproar. However, I'm supposed to be talking about vitamins, aren't I?
Anyway, you can choose to believe it or not, but there is way more evidence in favor of vitamins than against them. In fact, the "evidence" against them is mostly speculation. Do you know what your body does once it has no more need for a certain vitamin that you've been super-dosing? It simply turns the rest into waste and expels it from the body. This isn't true with commercial drugs. You take those in large amounts, and you'll do serious, if not lasting harm to your body.
How do you think people survive(d) and are even healthy in other cultures where they don't have health care or any sanitary practices? The food they eat is far more vitamin rich than what we generally eat in America. Not only do they mostly eat plants raw, but they eat far more of them than we do. Certain raw plants are simply saturated with vitamins, and those people learned over time which ones made them the most healthy.
I hope this has cleared up some of the false ideas of vitamins. I'd highly suggest that documentary, but I forgot the name. If we still have it from the library, I'll post the title of it here for anyone who wants to see it.