I think this is the best take. OP, multivitamins do work. Of course you need to fix your diet, of course it’s better to ingest the vitamin with the food so it can be absorbed better. Of course you should talk to a doctor. But if you have a deficiency of an important vitamin such as C or D, you will notice the difference.

Regarding overdoses, it is almost impossible to hurt yourself by taking a typical OTC multivitamin pill.

Consider some specific foods which give you a boost of the vitamin, such as canned tuna for Omega-3, Brazil nuts for selenium, etc.

But, at the end of the day, the general recommendation is that multivitamins are safe and pretty decent. I wouldn’t recommend any drug to a random person on the internet but multivitamins are fine.

Source: my wife is a nutritionist and we do talk about this a lot. I have a great diet but do take vitamins regularly as a complement or when I’m sick.

Yeah I knew someone who was a real wtf in so many ways …. They gave up on multi-vitamins because their nails grew faster. Wtf, one of the few people with proof of a deficiency being helped by a multivitamin and they give up? Because inconvenient to be healthier?

If you're deficient and the form of the vitamin/mineral is something your body can absorb, supplements can be helpful. If you aren't deficient, some supplements have little effect (water soluble ones just get peed out, though can cause wear and tear on your kidneys and/or liver in the meantime), while others can cause overloads which can be as bad as or worse than deficiencies.

Personally, I try to meet my micronutritional needs with foods but I occasionally take supplements to "top up", either a multivitamin if there's no specific signs of deficiency, or specific supplements if there's signs I might be low in that one (each has a set of symptoms that are associated with deficiency).

It's like when you have a Berocca and your wee is a luminous yellow for your next few trips because your body can't absorb all of the extra vitamins isn't it?