[doublekill]

So what about:

> The Centers for Disease Control and Prevention found that nearly 10% of all Americans have a nutritional deficiency.

And what about very low, but non-deficient levels?

It very much depends how the study is designed: in this case they do not measure quality of life or disease progression, but clinical outcome. That is what OP was alluding to: if you are going to only look at clinical outcome and completely tar "effectiveness" with that, then that is a very one-sided view of health and well-being.

Osteoporose patients are at increased risk of vitamin K deficiency. Just because multivitamins are not effective at taking us to Mars, are you really going to recommend patients to spend their vitamin money on fresh fruits?

[arcticbull]

Right, sure, that aligns with what I suggested. That if you have a nutritional deficiency, they may be useful, but 86% of Americans take vitamins or some other nutritional supplements, but only 20-something percent of them have been diagnosed with any kind of condition indicating they may need them.

The analysis needs to come from the other direction: take one vitamin, and prove it does something. Don't load people up with 20 vitamins and hope. Here's a great breakdown of the state of common supplements and whether they do anything at all that I found here, actually, a while back [1]

I put the onus on you: tell me why I should be putting this into my body. Explain what benefit it would provide me. Rather than saying "well, if you have low but not deficient levels of some vitamins supplementation may do something" -- that's not how medical science works :) I mean, eating lots of things may do something, but the burden of proof is higher.

[1] https://informationisbeautiful.net/visualizations/snake-oil-...

[doublekill]

90 percent of the restaurant is eating, but just 20 percent of those are still hungry :). They can stop eating and return next week when they are starving.

For me it is proof enough that my wise mother told me take my vitamins, but more scientific: you have a vector of essential vitamins and minerals. There are thresholds for deficiency. There are optimal levels. Aim for optimal levels, and do not overdo it. Supplements can help with that, and easier and cheaper than a diet which includes all necessities. Low levels are suboptimal for you. Makes sense?

[arcticbull]

> For me it is proof enough that my wise mother told me take my vitamins.

That's not proof of anything.

> There are thresholds for deficiency. There are optimal levels.

And there are levels that cause toxicity.

> Supplements can help with that.

[citation needed] which is kind of the point of this article.

> ...and easier and cheaper than a diet which includes all necessities. Low levels are suboptimal for you. Makes sense?

Unless your diet already has you covered, in which case it's strictly harder and more expensive.

Again, you should look for evidence of improvement, that's what the scientific process is all about. I encourage you to embrace the scientific process and take a data driven approach to whether ingesting something is going to help, harm, or have no impact on you at all, instead of just listening to your mom. My mom is a saint, but she's not right about everything.

Worse yet, because multivitamins like all nutritional supplements are not regulated by the FDA, they can range from totally ineffective to half decent, but you have no way of really knowing. The most common magnesium supplement I've found on Amazon is only 19% bioavailable [1] as compared to a best-in-class 90%. Where does your multivitamin rank? That's just one specific example.

[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6683096/

[doublekill]

I just did. The research is divided into two: those that look at clinical outcomes (such as cardiac arrest) do not find that vitamins help. Those that look at quality of life indicators, recovery, infection severity, and muscle strength do find significant improvements of supplementation.

And they find no harm of normal use, but warn against dangerous toxicity effects of overdosing.

[arcticbull]

Without any regulation how do you know how effective your particular multivitamin is at making bioavailable any given vitamin or mineral, re: the study I posted showing a range of 19% to over 90% for magnesium? It's pretty much impossible to know if they do anything at all. Which brings me back to my point: if you have a specific issue, a specific supplement whose effectiveness if validated is likely way cheaper and much more effective -- otherwise, the advice I would give anyone is to eat their greens and stop fretting.