Multi-Vitamins: Are They of Any Value?

During a recent conversation about health and nutrition the subject of multi-vitamins was raised. My friend insisted that she’d read (though certainly not in The Straight Dope!) that multi-vitamins were basically useless. Useless from a nutritional point of view, that is, since they are obviously of great value to the folks at GNC, for instance. She even went so far as to claim reading that those fortunate individuals who make their livings cleaning out porta-johns have reported finding undigested vitamin pills, with the brand name still visible, resting atop filter screens amid the muck and mire. Urban legend? Dunno. But what’s the Straight Dope? Are multi-vitamins of any nutritional value whatsoever?

BTW, Cecil, if you wanted to tackle this one yourself that’d be fine by me!

Here’s a previous discussion:

http://boards.straightdope.com/sdmb/showthread.php?threadid=31768

During a Physiology class in College we were discussing nurtrition and I asked the very same question you did to the professor. His answer, as I remember it, went something like this.

  1. If you eat an appropriate amount of food of high nutritional value and quality you would have no reason to take vitamins. But if you snack during the day, don’t eat appropriate foods (unprocessed or fast foods for example) then vitamins can help fill in the gaps for missing minerals your body might need. He also mentioned that stress can increase the need for certain chemicals and vitamins.

Keep in mind that millions of people around the world never take a single vitamin and manage to live quite healthy lives so how important could they be!

  1. Most people take more vitamins than they really need and much of it ends up in urine… at least the water soluable parts. He said that Americans have the most expensive urine in the world! So mega dosing is a problem and often times multiple vitamins have more of a particular chemical than you really need but your body gets rid of it anyway. In other words, taking a One-A-Day is okay… taking 10 of them a day is dumb and could harm you.

Regarding the finding of undigested vitamins in porta-pottys… I think that’s more urban legend than truth.

BTW, I have found that taking vitamins, particularly C and E do have a positive effect on my health. I have less colds and flus than I use to and when I get them they are less severe and don’t seem to last as long. Could this be the placebo effect? Probably not since I noticed the change over a 15 year period…

I abide by the Pauling theory of vitamin C, which I believed I noted in the link posted previously. I also said that mainstream frowned on vitamin C as being any help for colds, but now they’ve made a 20 degree turn. (Hey, every little bit helps.)

I’ve also noted that doctors, nutritionists, etc. have always stated that you don’t need pills, but when asked if they take any, they admit they take Vitamin C and/or E and possibly others.

Of course if you eat healthfully you don’t need any supplements (except possibly vitamin C). But who does? A multivitamin is insurance and cannot do any harm, so long as it’s a multivitamin and not excessive amounts of the fat soluble vitamins, especially A or D.

Pregnant women also are usually advised by prenatal care providers to take a multivitamin supplement including calcium and folic acid(usually in the form of prenatal vitamins). Unless a pregnant woman can consume 400 micrograms (ug) of folic acid daily in her food, she should take folic acid,which may prevent spina bifida and other neural tube defects in the baby.