I learnt a few years ago that even vitamin and mineral supplements can be lethally toxic if an overdose is taken, when I saw a program on TV. A family was moving houses that week, so Mum had packed the contents of the medicine cabinet, along with just about everything else in the house. Their little boy went digging in the box, found his vitamins, and started eating them like they were Halloween candy without telling anyone. By morning he had flu-like symptoms. Mum wasn't worried until she found spilled vitamins on his clothes, and around half his bedroom. She rushed him to hospital, and his stomach had to be pumped. He'd taken in too much iron or something. The boy was fine, but he learnt his lesson.



The thing I'm wondering about is, what about people who take several different types of multivitamins? Potentially, one person could be taking a different vitamin geared for their age, their gender, their level of physical activity, menopause or pregnancy, and a general multivitamin just to make sure they're getting everything they need. But most of those would have several components in common, resulting in the person getting several times their daily requirements for some vitamins or minerals. My question is, at what level do each of the various vitamins and minerals become toxic? How much is too much?

Usually you have to take very high doses to get toxic effects, any excess is, in the majority of cases, excreted out. For example, it is quite easy here to get vitamin D supplements with many times the recommended dose (30mcg vs the RDA of 5mcg), I get these on prescription once in a while when my levels drop low due to winter, red hair + freckles, and staying indoors due to bad weather The majority of vitamins are water-soluble, and so any excess is removed in urine. Fat soluble vitamins are usually where you would have a risk of toxic effects as these are more easily stored.

For the majority of people, there is no need to take multivitamins as it is fairly easy to get your required amounts, even on an "unbalanced" diet. I do take a multivitamin due to my very restricted diet, although my blood tests usually come back fine (with the exception of Vit. D mentioned above), so it is more a peace of mind thing for me, and I suspect for many people. I only do this in winter, as my diet in summer is much higher in fresh fruit and veg content. The levels at which toxic doses occur are also very high compared to daily intake, if you take for example vitamin C, the RDA is 90mg, and the upper limit is 2000mg, some of the B-vitamins have lower ratios if I remember. More common side effects are things like diahorrea, especially from supplements with iron.

Thanks for the link, I found it very helpful. I was just thinking about all those health nuts out there who think you have to take ten supplements a day or something crazy. Personally, I just take one general, because I don't eat as many fruit or veg as I should, and an iron complex because I'm a regular blood donor, and a female.

It all depends on what kinds of vitamins were in the multivitamin tablets consumed and how many were eaten. While many supplements are relatively non-toxic up to very high amounts (e.g., you could take a single dose of 10 gms of vitamin C or 2000 IU of vitamin E without having any serious reaction), others are extremely toxic in smaller overdoses, such as vitamin A. Generally, the severe toxicity would appear quickly, so if the patient is still all right probably no problems will arise. Also, keep in mind that multivitamins usually have pathetically small doses of all their component vitamins and minerals.

An important distinction should be made between the dose of supplements required to prevent vitamin or mineral deficiency disease -- which is extremely low -- and the dose required to gain beneficial health effects beyond just avoiding vitamin or mineral deficiency disease. The Medical Establishment, which lives in terror that its captive patients will ever gain control over their own health by being able to access effective non-prescription treatments which the Establishment cannot control, always pretends that the only possible effect that supplements can have is to avoid vitamin or mineral deficiency disease. But in fact, it is the much higher doses which can produce the truly beneficial health effects of reducing cancer, diabetes, and heart disease risk, but they don't want you to believe any of the thousands of scientific studies which confirm these benefits.

It is best to take several supplements in low dose that a few ones at high doses. Apart from reducing the risk of side effects, a multiple combination of low-dose supplements enhances the benefit of each individual vitamin etc. so the net effect is a much more powerful effect with few side effects.

That's some good advice, thank you. I take Centrum, which is a low-dose multivitamin, and additional Iron in a 'high' dose. Altogether I get about half my daily limit of Iron from my supplements, and I mean 'limit', not 'recommended dosage'. I looked it up on the internet, and I found that the highest ammount of Iron an adult woman can take before it starts becoming unhealthy is 45mg. I get 23mg per day, 8 from my Centrum, and 15 from my additional Iron supplement. On days when I feel like I'm going to faint, like when I've recently donated blood, and then my fertility cycle kicks in, I might take two Iron tablets, but I only do that on rare occassion, never more than once a month, because I know it takes the body longer than with most vitamins to get rid of excess iron.

Well, quite a few vitamins are lipohilic and do not get secreted efficiently. These generally carry the highest risk for overdosing, as they may accumulate to some extent. In many cases and on normal diets many supplements have little beneficial effects. In contrast to what Marat claims, there is little evidence that high doses have wide-ranging beneficial effects (conspiracies aside).

Iron is one of those from which many women actually do benefit, though, especially on diet with low iron content. The toxicity is, for the most part low, though one should be careful e.g. in cases of infections or intestine problems, as high levels of available iron can allow bacteria to grow more efficiently. This also goes for pathogenic ones. Also note that adverse effect levels are usually rough estimates. One should try not to use those levels as hard safety limits.

Excess of everything is bad. The same rule applies to vitamins.

The risk is especially greater for fat soluble vitamins, the absorption process of which is extremely efficient and much more than required amount can be absorbed into the body. Thus when an overdose is taken, extra amount is absorbed and toxic effects are produced.

I recently started taking Selenium in addition to my other supplements. It's an antioxidant which is supposed to greatly reduce the chances of me getting cancer. Would anyone care to comment on that?

Some studies have shown selenium to be effective in the prevention of some cancers. However, the therapeutic window for selenium is quite narrow, so I would be very careful not to take too much.

Personally, I would avoid micro-nutrient supplements unless you've been diagnosed as deficient by a licensed MD [which I am not]. This is just my opinion though, as many of the effects of trace nutrient deficiency or overdose are not that well understood. I would ere on the side of caution.

Selenum is a well established antioxidant and was found to be beneficial in cancer in laboratory experiments. Its benefit on human cancer in everyday situations has not been proved beyond doubt. I have seen many people who have been taking selenium daily for years and have not reported any significant side effects.

Can anyone tell me what the window quantity is exactly? My tablets are 200 Micrograms. What does Selenium dioxide do? What makes it so dangerous? Can anybody recommend a safer antioxidant? And what is a brazil nut? I eat a snack box consisting of 30 raisins, 10 cashews, 5 pecans, and 10 almonds every day. I make them myself. I find my snack boxes are excellent for the digestion system.