Tips For Choosing The Best Multivitamin

September 30, 2025 by Dr. Steve Chaney

Don’t Fall For Misleading Marketing Claims

Author: Dr. Stephen Chaney

There are lots of multivitamin-multimineral products in the marketplace. Every company must differentiate their product from the competition to win their market share. When that differentiation is based on quality, purity, and clinical proof the product works, I am all for it. May the best company win.

However, the pressure to win market share is intense. Quality controls and clinical studies are expensive. All too often companies try to differentiate their multivitamin-multimineral products based on marketing hype and/or worthless ingredients that subtract money from your wallet without adding anything of value to your health.

With so many claims and counter claims in the marketplace, it has become almost impossible for the average consumer to know which claims are true and which are false. Everyone wants to get the best multivitamin-multimineral for their health at the least possible cost. Perhaps that is why I am so frequently asked for guidance on how to choose the best multivitamin.

In this week’s article, I will give you 6 tips you can use to select the multivitamin-multimineral product that is best for you. I will tell you what to look for in a good multivitamin and which marketing claims you should just ignore.

But first, we need to look at how nutritional standards are set.

How Are Nutritional Standards Set?

The standards for nutritional supplements are set in a two-step process.

Step 1: In the first step, The Institute of Medicine (IOM) of the National Academies of Sciences selects a committee of experts called the Food and Nutrition Board to set standards for a specific set of nutrients. They set 3 kinds of standards:

Recommended Dietary Allowances or RDAs are the average daily dietary intake level sufficient to meet the nutrient requirements of nearly all (97-98 percent) healthy individuals in a group.

Adequate Intakes or AIs are established when evidence is insufficient to develop an RDA and are set at a level assumed to ensure nutritional adequacy.

Where toxicity is a potential concern, Tolerable Upper Limits or ULs represent the maximum daily intake unlikely to cause adverse health effects.

Just to confuse things, all three standards are part of what is called Dietary Reference Intakes or DRIs.

Step 2: The DRIs are specific for age, gender, pregnancy & lactation. It would be hopelessly complicated to use DRIs for nutrition labels on foods and supplements. Therefore, the FDA sets a Daily Value (DV) for the purposes of food and supplement labeling. Originally, DVs were set based on the highest DRI for a specific nutrient. However, currently the DV is an average of DRIs for adults and children 4 years and older. It is not identical to the RDA or DRI for any specific group, but it is a useful standard for supplement labels.

With this information in mind, let’s get back to the 6 tips for choosing the best multivitamin.

#1: Good Product Design Matters

Comparing nutrition labels on multivitamin-multimineral supplements can be tricky. Some supplements only provide 5-10% of the Daily Value (DV) for some nutrients. Are those nutrients unimportant? Some supplements provide hundreds or thousands % of the DV for other nutrients. Is more better?

Often companies will quote some random scientist or one or two clinical studies to support the mix of nutrients they include in their multivitamin-multimineral supplement. Don’t fall for their marketing hype.

The only valid nutritional standards for multivitamin-multimineral products in the United States are the DV standards set by the Food & Nutrition Board of the Institute of Medicine. They are the standards you should look for in evaluating nutrition labels.

That’s because the National Academies of Sciences is the real deal. The National Academies represents the top 1-2% of scientists in the country. To be selected to the National Academies you must be nominated by an Academy member and voted on by the entire Academy. Selection is based on your research contributions over decades. (No, I am not a member of the Academy, but thanks for thinking that question).

The Institute of Medicine of the National Academies of Sciences selects the best of the best to serve on the Food and Nutrition Board. They are world renowned experts who review all the pertinent literature (not just one or two studies) They decide on which nutrients are essential and how much of them we need.

It always amazes me that some companies pretend they know more than the Food and Nutrition Board. It amazes me even more that some people believe those companies.

With that in mind, this is what to look for when comparing nutrition labels:

The FDA has set Daily Value (DV) recommendations for 24 vitamins and minerals (23 if the supplement is for adult men or postmenopausal women and does not contain iron). Make sure your multivitamin-multimineral has all 24. Count them. If a company leaves out an essential nutrient, they are not required to list it on the label.

The Food and Nutrition Board has classified several other nutrients as essential but does not feel there have been enough studies to establish a DRI. Without a DRI, the FDA cannot set a DV. Those nutrients are represented with a “dagger” symbol on the label with the footnote “Daily Value not established”. These can be useful additions to a multivitamin-multimineral supplement, provided they are not present in excess.

Ignore anything companies list on their nutrition labels that does not have a %DV value or a “dagger” symbol. This is often just marketing hype. In some cases, the ingredients have no proven benefit. In many other cases, it’s just not possible to put enough of them in a multivitamin-multimineral tablet to provide any real benefit.

#2: Look For Balance

This is another area in which we need to be guided by the recommendations of the Food and Nutrition Board of the Institute of Medicine. One of the reasons many experts recommend that people get their vitamins and minerals from foods rather than from supplements is because many supplements are unbalanced. That’s a problem because there are many cases in which too much of one nutrient can interfere with the absorption or metabolism of related nutrients. For example,

Zinc and copper compete for absorption. For best absorption and maximal utilization by the body, the zinc to copper ratio should be close to 1:1 based on DV.

B vitamins should be in balance. Look for a multivitamin-multimineral supplement that provides 100-200% of the DV for all 8 essential B vitamins. (The levels can be higher in a B Complex supplement, but they should still be in balance.)

Some manufacturers will leave out the expensive B vitamins and load up on the cheap ones. This saves them money. It also allows them to use marketing terms like “mega” or “super”. A supplement that provides 50% or less of the DV for some B vitamins and 1,000% or more of the DV for others is ridiculous. There is absolutely no rationale for a ratio like that except to mislead consumers.

As for the other nutrients in multivitamin-multimineral supplements, they should not be significantly below 50% or significantly above 250% of the DV.

Calcium, magnesium, and phosphorous are a special case. They are bulky, so many manufacturers only provide 5-10% of them in their multivitamin-multimineral supplements. This is not ideal because many of the nutrients in a multivitamin-multimineral supplement are required for optimal utilization of calcium and magnesium in bone formation.

Many Americans get only 50% of the DV for calcium and magnesium in their diet. Thus, it makes good sense to provide 30-50% of the DV for calcium and magnesium in a multivitamin multimineral supplement. Most Americans get close to the DV for phosphorous from their diet, so the amount of phosphorous in a supplement is not particularly important.

#3: Don’t Fall For The Hype

In their attempts to differentiate themselves, many companies claim that they use a more natural or a better utilized form of the vitamin or mineral than their competitors. Ignore those claims. They are just marketing hype. For example,

In previous issues of “Health Tips From the Professor” I have debunked the claims that folate and methyl folate are more natural, safer and more effective than folic acid. The claims that alternate chemical forms of other vitamins are more natural, safer, and more effective are equally bogus.

The claims by some manufacturers that they use a form of calcium that is more readily absorbed are not just misleading. That is the wrong question. Calcium in our bloodstream can do bad things (like calcification and hardening of the arteries) if it is not quickly utilized for bone formation.

- Thus, the important question is how well the calcium is utilized for bone formation. Look for clinical studies showing that the calcium in their multivitamin-multimineral supplement is efficiently utilized for bone formation rather than hype about how quickly it gets into the bloodstream.

There is a good reason that many supplement companies continue to use ingredients like folic acid for B9, cyanocobalamin for B12, pyridoxine for B6, etc. All of them are supported by hundreds of clinical studies showing that they are safe and effective. I have no issue with companies choosing to use different forms of these vitamins. Just don’t fall for their hype that the forms they are using are somehow more natural, safer or more effective than the traditionally used forms of the same vitamin.

#4: Don’t Fall For Buzz Words

Some manufacturers attempt to differentiate their products by claiming they are natural, organic, non-GMO, or are made from food. The companies are attaching buzz words to their product that they know resonate with the American people. Don’t believe them. Those claims are all bogus. They are marketing hype. For example,

There is no standard for “natural” so companies are not required to provide any evidence to back up their claim. If they claim that their product is natural, ask for a detailed list of the source and processing method for all their ingredients. If they are unwilling or unable to provide you with that information, don’t believe their claim of natural.

“Organic” certification for a supplement simply means that ingredients come from crops raised using organic methods. It is no guarantee of purity. Organically grown crops can still be contaminated if the air, soil or water is contaminated from any nearby pollution source. For example, ground water pollution is the major source of heavy metal contamination often seen in rice-derived ingredients. It is far more important to select your supplement based on rigorous quality control standards that assure it is pure than to rely on “organic” on the label.

A “non-GMO” designation is useful for foods and for protein, but it is meaningless for the ingredients in a multivitamin-multimineral supplement. Those ingredients have been extensively purified. They contain no genetic information. They are chemically indistinguishable from purified ingredients obtained from GMO sources. If you would like more detailed information about the GMO controversy, I have provided a balanced perspective on GMO in a video.

Claims by some companies that their vitamins are derived from foods are completely bogus. That is a physical impossibility. For example, let’s look at what it would take to provide the DV for just 3 of the nutrients in a single multivitamin pill, assuming they started with the best food sources of those 3 nutrients:

- It would take 1 cup of cooked lentils, 2 cups of cooked spinach, or 4 cups of cooked broccoli to provide the DV for folic acid.

- It would take 1 cup of sunflower seeds, 1.5 cups of pistachio nuts, or 7 ounces of cooked tuna to provide the DV for vitamin B6.

- It would take 5 ounces of cooked chicken breast, 1 cup of peanuts, or 6 cups of green peas to provide the DV for niacin.

That’s just 3 nutrients and one multivitamin tablet. You do the math. If they lie to you about their vitamins coming from food, they will probably lie about other things as well.

#5: Don’t Fall For Scare Tactics

Some companies try to scare you into buying their products by claiming their competitors are using unsafe ingredients. These claims are usually bogus, but it is useful to understand where this misinformation comes from.

There is a lot of unfounded hysteria on the internet about product ingredients. Much of this hysteria has been fueled by a few well-known bloggers. I believe their intentions were pure in the beginning. They started by warning the public about truly dangerous ingredients like artificial colors, flavors, preservatives and sweeteners.

However, blogging has a dark side. To capture a large audience, your blog posts need to be sensational every week. As the weeks go by it becomes harder and harder to find subject matter that is both sensational and accurate. That’s when some bloggers go over to “the dark side”.

They become more concerned about the size of their audience than the accuracy of the information they post. They start vilifying ingredients that are perfectly safe as long as the manufacturer purifies them correctly and tests them for purity. These are ingredients which might be of concern for products made by a company with poor quality controls but pose no concern for products made by a company with high quality control standards. In other words, they should not be spreading hysteria about the ingredient. They should focus on some of the real quality control issues in our industry.

To help you sort through all the hysteria about product ingredients, I have previously published a two-part series on ingredients in which I sorted through the claims and divided common ingredients into the good, the bad, and the ugly.

#6: Demand Proof

This is the most important tip of all. Many companies make wild claims about their products but feel no need to back up their claims. Ignore their hype and demand they give proof to back up their claims.

If they claim their products are pure, ask how many quality control tests they run on their products.

If they claim their products work, ask for proof. Ask for clinical studies…

- That have been done with people, not with animals, cell culture, or test tubes*

- That have been published in peer-reviewed scientific journals.

- That have been done with their product, not studies done with another product.

*Animal, cell culture and test tube studies are valid if they are used to identify a potential mechanism of action but should not be cited as proof the product works. For ethical reasons, I prefer companies that do not use animal studies.

The Bottom Line

Everyone would like to get the best multivitamin-multimineral for their health at the least possible cost. However, there are lots of multivitamin-multimineral products in the marketplace. The pressure to win market share is intense. Quality controls and clinical studies are expensive. All too often companies try to differentiate their multivitamin-multimineral products based on marketing hype.

With so many claims and counter claims in the marketplace, it has become almost impossible for the average consumer to know how to choose the best multivitamin-multimineral product. In this week’s article, I have given you 6 tips you can use to select the multivitamin-multimineral product that is best for you. I have told you what to look for in a good multivitamin and which marketing claims you should just ignore. In summary:

Start with the nutrition label. A good multivitamin-multimineral supplement should contain all 24 essential nutrients recommended by the Food and Nutrition Board of the Institute of Medicine (23 if the supplement is without iron). Anything else is probably marketing hype.

Make sure the nutrients are in the correct balance. Again, your evaluation should be guided by the Institute of Medicine.

Don’t fall for the hype. Many companies claim that they use a more natural, safer, or better utilized form of certain vitamins or minerals than their competitors. Ignore those claims. They are usually just marketing hype

Don’t fall for buzz words. Some companies attempt to differentiate their products by claiming they are natural, organic, non-GMO, or are made from food. The companies are attaching buzz words to their product that they know resonate with the American people. Don’t believe them. Those claims are all bogus. They do nothing to improve your health. They are marketing hype.

Don’t fall for scare tactics. Some companies try to scare you into buying their products by claiming their competitors are using unsafe ingredients. These claims are usually bogus.

Demand poof. This is the most important tip of all. Many companies make wild claims about their products but feel no need to back up their claims. Ignore their hype and demand they give proof to back up their claims.

If they claim their products are pure, ask how many quality control tests they run on their products.

If they claim their products work, ask for proof. Ask for clinical studies…

- That have been done with people, not with animals, cell culture, or test tubes.

- That have been published in peer-reviewed scientific journals.

- That have been done with their product, not studies done with another product.

For more details about each of those tips, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

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My posts and “Health Tips From the Professor” articles carefully avoid claims about any brand of supplement or manufacturer of supplements. However, I am often asked by representatives of supplement companies if they can share them with their customers.

My answer is, “Yes, as long as you share only the article without any additions or alterations. In particular, you should avoid adding any mention of your company or your company’s products. If you were to do that, you could be making what the FTC and FDA consider a “misleading health claim” that could result in legal action against you and the company you represent.

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

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About The Author

Dr. Chaney has a BS in Chemistry from Duke University and a PhD in Biochemistry from UCLA. He is Professor Emeritus from the University of North Carolina where he taught biochemistry and nutrition to medical and dental students for 40 years. Dr. Chaney won numerous teaching awards at UNC, including the Academy of Educators “Excellence in Teaching Lifetime Achievement Award”.

Dr Chaney also ran an active cancer research program at UNC and published over 100 scientific articles and reviews in peer-reviewed scientific journals. In addition, he authored two chapters on nutrition in one of the leading biochemistry text books for medical students.

Since retiring from the University of North Carolina, he has been writing a weekly health blog called “Health Tips From the Professor”. He has also written two best-selling books, “Slaying the Food Myths” and “Slaying the Supplement Myths”. And most recently he has created an online lifestyle change course, “Create Your Personal Health Zone”. For more information visit https://chaneyhealth.com.

For the past 45 years Dr. Chaney and his wife Suzanne have been helping people improve their health holistically through a combination of good diet, exercise, weight control and appropriate supplementation.

Are Multivitamins A Waste Of Money?

December 24, 2013 by Dr. Steve Chaney

Don’t Throw Your Vitamins Away Yet

Author: Dr. Stephen Chaney

The Professor is annoyed. Two things really irritate me:

Charlatans who cherry pick studies to “prove” that their snake oil supplements will cure what ails you.
Doctors who proclaim that vitamins are a waste of money without understanding the science behind the studies they are quoting.

Are Multivitamins A Waste Of Money?

You’ve seen the headlines telling you that “the experts” have concluded that multivitamins are a waste of money. You might be wondering “What’s behind these headlines? Who are these experts, and what is their evidence?”

Let’s start at the beginning. The article (Gualler et al., Annals of Internal Medicine, 159: 850-851, 2013) that generated all of the headlines was an editorial, which means it is an opinion piece, not a scientific study. It represents the opinion of five very prominent doctors, but it is, at the end of the day, just their opinion. Many other well respected experts disagree with their opinion.

They based their editorial on three recently published studies:

The first study reported that vitamin and mineral supplements did not decrease the risk of heart disease and cancer in healthy individuals (Fortmann et al., Annals of Internal Medicine, 159, doi: 10.7326/003-4815-159-12-201312170-00729)

The second study reported that multivitamins did not affect cognitive function in healthy male physicians aged 65 and older (Gradstein et al, Annals of Internal Medicine, 159, 806-814, 2013)

The third study concluded that multivitamins did not reduce the risk of a second heart attack in patients who had previously had a heart attack and were receiving appropriate medical therapy.

These were all large, well designed studies, so it would be tempting to conclude that the headlines were right. Maybe vitamins are a waste of money.

But, what if the whole underlying premise of these studies was flawed? Let’s examine that possibility by examining the flawed premises behind these and other studies.

What’s Wrong With These Studies?

#1) These studies were too narrowly focused.

Multivitamins and individual vitamins and minerals are not magic bullets. They are not drugs. They are meant to fill nutritional gaps in our diet – not prevent or cure disease. We should be asking whether holistic approaches can prevent or cure disease – not whether individual nutrients can do so.

One of the examples that I love to use, because it really made an impression on me as a young scientist, occurred at an International Cancer Symposium I attended more than 30 years ago. I attended a session in which an internally renowned expert was giving his talk on colon cancer. He said, “I can show you, unequivocally, that colon cancer risk is significantly decreased by a lifestyle that includes a high-fiber diet, a low-fat diet, adequate calcium, adequate B-vitamins, exercise and weight control. But I can’t show you that any one of them, by themselves, is effective.”

The question that came to me as I heard him speak was: “What’s the message that a responsible scientist or responsible health professional should be giving to their patients or the people that they’re advising?” You’ve probably heard experts saying:

“Don’t worry about the fat content of your diet. It can’t be shown to increase the risk of colon cancer.”
“Don’t worry about calcium. It doesn’t decrease the risk of colon cancer”
“Don’t worry about B-vitamins. They don’t decrease the risk”
“Don’t worry about fiber. It can’t be shown to decrease the risk either”

But, is that the message that we should be giving people – that nothing matters? Shouldn’t we really be saying what that doctor said many years ago – that a lifestyle that includes all of those things significantly decreases the risk of colon cancer?

#2) These studies were destined to fail.

It’s almost impossible to prove that any single intervention prevents disease when you are starting with a healthy population (something we scientists refer to as a primary prevention study).

For example, in “Health Tips From the Professor” just a couple of weeks ago I shared with you that even when you combine all of the published studies with tens of thousands of patients, it is impossible to prove that stain drugs prevent heart attacks in healthy individuals.

If you can’t show that statins prevent heart disease in healthy people, why would you expect to be able to show that vitamins or minerals prevent heart attacks in healthy people?

I can’t resist pointing out that this perfectly illustrates the pro-drug, anti-supplement bias that is so prevalent among many of my medical colleagues. I haven’t seen a single editorial or headline suggesting that statin drugs might be a waste of money for healthy individuals.

#3) These studies simply asked the wrong questions.

For example, the third study described in the editorial was asking whether multivitamins reduced the risk of a second heart attack in patients who were receiving “appropriate medical therapy”. What does “appropriate medical therapy” mean, you might ask? It means that those patients were on 4 or 5 drugs, with all of their side effects.

In reality the study was not asking whether multivitamins reduced the risk of a second heart attack. The study asked whether multivitamins had any additional benefits for individuals who were taking 4 or 5 drugs to reduce their risk of a second heart attack. That’s a totally different question.

There are lots of examples of this paradigm. For example, 17 years ago the Cambridge Heart Antioxidant Study showed that vitamin E significant decreased heart attack risk in patients with severe cardiovascular disease (Stephens et al, The Lancet, 347: 781-786, 1996). Patients in that study were taking one or two medications. However, in today’s world that would be considered unethical. The standard medical treatment for high risk heart disease patients today is 4 or 5 drugs, and when patients are receiving that many medications it is no longer possible to demonstrate a benefit of vitamin E. The story is similar for omega-3 fatty acids.

That poses a dilemma. What recent studies show is that individual nutrients don’t reduce the risk of a second heart attack in someone who is receiving “standard of care” medical treatment.

But that’s not the question I am interested in. I’d like to know whether natural approaches might be just as effective as the drugs or whether natural approaches might allow one to use fewer drugs or lower doses. I’d like to avoid all of the side effects of those drugs if I could.

What about you? What questions would you like answered? Do these studies answer those questions?

What Was Overlooked In Those Studies

The studies did show conclusively that there were no harmful effects from supplementing except for high dose beta-carotene in smokers. Somehow that information never made it into the headlines.

The Bottom Line

Don’t pay much attention to the reports that supplements don’t work and are a waste of money. Those studies are fundamentally flawed.

Don’t pay much attention to the reports claiming that vitamins will hurt you. Except for beta-carotene in smokers the latest studies showed no evidence of harm.

On the other hand, don’t expect miracles from your vitamins. If you spend your time sitting in front of the TV set eating pizza & drinking sodas, popping a vitamin pill won’t prevent much of anything.

Finally, holistic approaches are often as effective as drug therapy – without the side effects. Your vitamins can be an important part of a holistic approach to better health that includes weight control, a good diet and exercise.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

Use of Sports Supplements By Young Athletes

October 31, 2013 by Dr. Steve Chaney

Are Sports Supplements Effective? Are They Safe?

Author: Dr. Pierre DuBois

In recent years, the use of sports supplements by young athletes has increased dramatically. The most commonly used sports supplements among teenagers of all ages were vitamins and minerals, though “ergogenic aids” are used by some teen athletes specifically to enhance performance. Among these performance-enhancing supplements are substances such as caffeine, creatine, ephedra and other stimulants, human growth hormone (HGH) and anabolic steroids.

Of the vitamin and mineral supplements, mutivitamins, vitamin C, calcium and iron were reported as being taken most often. While the risks of taking vitamin supplements is relatively low, there is some concern that young athletes may then progress to taking more dangerous substances under the impression that they are as harmless as vitamins and minerals. And while the risk of overdose with vitamins and minerals is low, it is not nonexistent, and some vitamins can be toxic when too much is taken (such as iron and vitamin A) or may interact with other vitamins or drugs.

Although many performance-enhancing supplements are advertised as being safe – especially those made from natural compounds – a great number of them have not been tested by any regulatory agency, so their actual safety is not known. In addition, there are no formal guidelines for dosage in many cases, so there could be adverse side effects if too much is inadvertently taken.

The pressure to excel at sports is greater than ever, and there is increasing competition to get into elite sports programs where they have a better chance of being discovered by professional sports scouts looking for the next big star. The possibility of fame and fortune can be a strong enticement to young athletes to try performance-enhancing supplements to give them an edge over their competition. And often it is their coach that suggests or encourages this practice.

According to studies done on high school athletes, they report taking supplements to not only enhance performance, but also to encourage growth and muscle development, prevent illness and reduce fatigue. Supplement use was greatest among athletes who practiced two or more different sports and those who were required to “bulk up”, such as wrestlers and weight lifters.

While the opinions of friends, teammates and coaches were a big influence on the decision of young football players to take supplements (particularly creatine), it was their parents who had the greatest amount of influence on their decision. So it is incredibly important for parents to be educated as to the benefits and drawbacks of each of these supplements for young athletes.

The Bottom Line:

There is tremendous pressure on teenage athletes to qualify for elite programs that will increase their chances of being selected for the top college teams and eventually getting onto professional teams. Because of that, the use of sports supplements by teenage athletes is commonplace.

Vitamin and mineral supplements are generally harmless unless taken in excessive amounts.

Performance-enhancing sports supplements, on the other hand, are poorly regulated. Many are useless and others are potentially harmful. In next week’s “Health Tips From The Professor”, I’ll give you some examples of sports supplements you might want to avoid.

If you are the parent of a teen athlete, have a conversation with your child about supplements. Don’t lecture, but involve them in the process of doing research. You may be surprised what you both find.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

Multivitamin Supplements May Reduce Breast Cancer Mortality

October 29, 2013 by Dr. Steve Chaney

Can A Multivitamin A Day Keep Breast Cancer At Bay?

Author: Dr. Stephen Chaney

A few weeks ago I wrote about soy and breast cancer survival. You’ve probably seen the latest headlines: “Multivitamin Supplements May Reduce Breast Cancer Mortality” and are wondering if they could possibly be true. After all, wasn’t it just a short time ago that the headlines said “Multivitamin supplements have no effect on breast cancer mortality” or that “Multivitamins may increase your risk of death”?

With all the conflicting headlines, you have every right to be skeptical about the latest news. So perhaps we should start with looking at the previous studies and discussing why they disagree.

What do we know about multivitamin use and breast cancer survival?

Three very large studies have reported no correlation between multivitamin use and breast cancer incidence. So it is pretty clear that multivitamins don’t prevent breast cancer.

However, breast cancer incidence and breast cancer survival are two different things. In the first case you are starting with healthy women and asking how many of them develop cancer. That is what we scientists call a primary prevention study. It is very difficult to prove the effectiveness of any intervention in a primary prevention study. In the second case you are starting with a sick population and asking if an intervention provides a benefit. It is much easier to prove whether or not an intervention is effective in this kind of study.

There, have been several small studies looking at the effect of vitamin supplementation in women who already had breast cancer. While the results have been mixed, the majority of the studies showed that vitamin supplementation did appear to reduce breast cancer recurrence and mortality.

What makes this study different?

The women in this study were part of 161,608 women enrolled the Women’s Health Initiative (WHI) study to investigate the effects of multivitamin use in post-menopausal women. In fact, this was one of the studies to report no effect of multivitamin use on the incidence of breast cancer (Neuhouser et al, Arch. Intern. Med., 169: 294-304, 2009).

What the present study did was to look at the those women in the WHI who did develop breast cancer during the previous study and followed them for an additional 7.9 years to see if multivitamin use affected breast cancer survival (Wasserthiel-Smoller et al, Breast Cancer Res. Treat., 141: 495-505, 3013).

This is the largest study of its kind (7,728 women). It started with an older and sicker group of women than previous studies. All of the women were 50-79 years old at the time the study began, and all of them had invasive breast cancer at the time of enrollment into the study.

The results were quite impressive. Multivitamin use improved survival by 30%, and the results were highly significant.

Strengths of the Study:

This was a large and very well controlled study. The authors did an excellent job of controlling for confounding variables that might have affected the outcome.

Multivitamin use was measured at multiple time points. It was assessed at enrollment into the original WHI study and at each subsequent doctor visit. The multivitamin usage for the purpose of data analysis was the usage at the time of breast cancer diagnosis, but the authors also corrected for any change in vitamin use post-diagnosis.

The study was in agreement with the majority of previous studies, further strengthening the conclusion that multivitamin use in women with breast cancer improves the likelihood of survival.

Weaknesses of the Study:

Because previous studies have been mixed with respect to the effect of multivitamins on breast cancer survival, further placebo controlled intervention studies will be required before multivitamin use becomes part of the standard of treatment for breast cancer patients.

Most of the women in the study were post-menopausal. It is unclear if multivitamins will provide the same benefit to pre-menopausal women with breast cancer.

This study measured consistent multivitamin use before and after the diagnosis of breast cancer. It did not look at women who began multivitamin use after diagnosis. So we have no idea whether starting multivitamin use after diagnosis would have also been beneficial.

The Bottom Line:

1) This study strongly suggests that multivitamin use may help improve your chances of survival if you are unlucky enough to develop breast cancer. While more studies are still needed, this study certainly strengthens the argument for multivitamin use.

2) The rap on multivitamins has always been that they aren’t needed by healthy people who have a good diet. However, multivitamins are important for assuring good nutritional status if your diet is not optimal or if you have increased nutritional needs – either because of your genetic makeup or because of illness.

3) The difficulty is that you usually don’t know if your genetics increases your vitamin needs, and once your disease has progressed far enough to be diagnosed it may be too late to improve disease outcome. That’s why many experts consider a multivitamin supplement as an inexpensive form of nutritional and health insurance. I concur.

4) As for the fear that multivitamins might just kill you, that hypothesis has been disproven by several subsequent studies including one published just a couple of weeks ago (Macpherson et al, Am. J. Clin. Nutr., doi: 10.3945/ajcn.112.o49304).

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.