What are the drawbacks of multi vitamins vs. specific supplements?

[HorseNut]

Sorry, wasn't sure where to put this. I've never understood why you might be advised to take, for example, vitamin C, D and iron supplements, instead of a general multi vitamin tablet which contain 100% of your RDA of those things. I currently take Vitamin C, B vitamins and iron supplements. I'm it thinking I need to add magnesium and Vitamin D. Is there benefit to keep adding specific pills instead of just changing to a (high quality) multi vitamin?

Individual supplements just means that you can tailor the doses/avoid excesses of certain substances, which can be useful for people with specific health conditions.

For example, I have chronic fatigue and hayfever and I take mega doses of vitamin c to help my body manage these conditions. It definitely seems to help me.

I also take a daily multivit/mineral, because CF means I don't always have the energy to prep/eat healthy food, but the vit. c levels in this are fairly low.

Thanks, that's useful to know

I think the drawbacks of specific supplements as opposed to a multivitamin is expense!
I swapped to a multivitamin after I realiesed I could be taking alot less tablets for cheaper that way.
I suppose their is a risk you could overdose on something but I imagine that would be very hard to do if you are just eating a normal diet.

It is not advisable to take iron long term (even at the rda) unless you have a deficiency.

Some components of multivitamins compete for absorption.

Multivitamins often contain the cheapest forms of the vitamin rather than the best absorbed e.g non methyl forms of b vitamins, calcium carbonate or d2.

Many contain fillers which may do more harm than good.

thanks @Clockface222 thats really helpful and makes sense. Is there a multivitamin brand or specific one you would recommend, if I was to switch to a multivitamin?

I like this one. It has methylated b vitamins and good forms of the others. It is also not too high, mainly just rda levels. My ferritin is low so I am happy that it contains some iron but you would need to check your ferritin is not high if you plan to take it long term.
https://peaksupps.co.uk/products/multivitamins-minerals-capsules-pure