I'm a few days late in commenting on two studies that were published this week suggesting that vitamin and mineral supplements are harmful. One study tracked 38,000 women starting when they were 55-69 years. The researchers asked them to fill out questionnaires periodically on their supplement usage (and a bunch of other things) and then they just waited for them to die (morbid, but true). Results showed that after 20 years, those women taking a vitamin and mineral supplement had a 2.4% higher risk of death than those who didn't take a supplement. Iron seemed to be the nutrient most associated with a higher risk of dying earlier.
A different study looked at 35,000 men who either took a selenium supplement (200 ug/d), a vitamin E supplement (400 IU/day), both supplements, or none. After tracking these guys for 7 to 12 years, those taking either supplement (or both) had a higher risk of developing prostate cancer (17% higher risk for those taking the vitamin E).
The fun in being late to report on these studies is that I can respond to many of the comments that are being posted on various news sites and other blogs. Some range from rather insightful to loony. And I apologize to anyone who's words I'm using below...but I just couldn't let these go without commentary:
"I would like to know who funded the study. Could it have been a pharmaceutical company?"
Dr. T: Both studies were funded by the National Cancer Institute. Why on earth would a pharma company pay the millions of dollars needed for these large studies?
"Big pharma profits down, no new drugs in the pipeline, running out of people to over medicate, time to attack vitamins! The bottom line.This study is a classic example of scientific reductionism being used to fulfil a particular need. In this case, it’s supplement bashing, a well-known preoccupation of Big Pharma."
Dr. T: Ah of course, this is why. Pharma companies want people to get sick so they somehow convinced the National Cancer Institute to give millions of dollars to university professors who then were in on it too and designed a study to make people die more quickly from taking supplements...."a well-known preoccupation of Big Pharma". I hope this person declines any drugs their physician prescribes to them for a life-threatening disease (all developed and proven effective from a pharma company) since they feel so strongly about "scientific reductionism". And if someone could kindly explain what that term even means, I would greatly appreciate it.
"Vitamins should not be taken to INCREASE LIFE SPAN. Vitamins should be taken to enhance life."
Dr. T: This is true, no one ever said vitamins were going to extend your life. But if they do cut your life short, are they really enhancing your life?
"Maybe they died in car accidents going to buy more vitamins"
Dr. T: This is actually the smartest comment in the bunch. The study looking at women and supplement use did not evaluate whether vitamins CAUSED early death, but rather they were looking for whether there was an association. It is possible that women who were already sick happened to be taking more vitamins. Or that these women who take vitamins have other behaviors that increase their risk of death. That said, the prostate study coming out in the same week, plus earlier studies showing similar results, all suggest that people need to think twice before taking a supplement (see below for more info on that).
"This is utter BS. Bad science is plaguing the world. Especially that which pertains to the use of vitamins. Countless studies of vitamin megadoses show phenomenally positive effects on human health. Of course, these are predominantly unheard studies as the pharmaceutical industry will stop at nothing to keep people on their meds instead of letting them take preventative measures with vitamins, natural assets that give our bodies the strength to fight disease."
Dr. T: It is possible this is the same person with the same conspiracy theory above. First off, these two studies are some of the highest quality research out there since they have tens of thousands of people. There are NO studies with tens of thousands of subjects looking at megadosing of vitamins. In fact, most of those studies have 10 to 50 people and results seem to always work best in people that are already deficient. For example, mega-dosing of iron helps children grow and learn in less developed countries (because they are low in iron). And finally, these studies are being published in top tier journals that are run independently by university professors...not pharma companies. And what exactly is a "natural asset"?
So back to the title...should you stop taking your supplements? Maybe. Some things to consider:
1. Do you drink fancy drinks containing vitamins, eat energy bars with vitamins, have a bowl of fortified breakfast cereal every day? If so, you really don't need a supplement.
2. You really don't need more than ~100% of the daily value in a supplement. If you are taking more than that, you may want to re-consider what you are taking.
3. You may only need to supplement selected vitamins and minerals. For example, a vitamin D supplement is really only needed for those living in northern locations or those who are never outside without sunscreen. Women who are menstruating and do not consume red meat probably need to take iron but men do not. Those who do not eat any fruits and vegetables (gasp!) should take a vitamin C supplement but if you are smart enough to eat those foods, you probably don't.
4. Is a "whole-food supplement" better than a regular supplement? At this point, we don't know. There are no big studies looking at food-based sources of vitamins and minerals and health. It may be that it doesn't matter where the vitamins come from. Or they may be better, but not clear yet. I would still stick to the 3 principles above until we have more information.
And I promised a friend I would look at natural remedies for cold and flu so hope to get to that topic next!