Supplement Questions clean
Do you know what’s in your supplement?

A trip to a grocery or health food store shows that there are many different kinds of supplements out there. It can be difficult for consumers to choose a particular supplement given the large number of options available and the wide variety of health claims. There is a dizzying array of options, doses, and formulations that can often leave consumers baffled.

What makes matters worse is the possibility that what is listed on a supplement label might be completely different than what is actually inside the bottle. Most recently, issues about fraudulent claims of the content of herbal supplements have been raised and are currently under investigation. Media reports on this inquiry sometimes incorrectly referred to the supplements in question as vitamins, highlighting the inattention to detail by journalists that incorrectly lump all supplements together.

However, that does not mean other dietary supplements can’t be scrutinized. A recent analysis of fish oil supplements in New Zealand has also raised concerns about the quality and freshness of those products and, possibly, other products containing omega-3 fatty acids. Again, these results cannot and should not be used to gauge all other supplements on the market, since quality supplements DO exist (despite what it might sound like on the news).

At the Linus Pauling Institute, we know that finding these high-quality supplements can be difficult. Although our online resource, the Micronutrient Information Center (MIC), provides information about vitamins, minerals, phytochemicals, and other nutrients commonly found in supplements, we do not research or recommend specific supplement brands or formulations. However, that doesn’t mean you are completely without resources to find a quality supplement.

Here are some places you can go for help:

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The US Pharmacopeial Convention (USP) is a nonprofit agency dedicated to verifying the quality, purity, and potency of dietary supplements. As part of their verification program, the USP audits the manufacturer’s facility and does an extensive review of quality control and manufacturing documentation to ensure that supplements are produced according to specifications. The USP also tests the supplements produced in this process, verifying that the product matches claims of quantity on labels. If a dietary supplement passes this review, it is awarded the USP Verified Mark. Although other companies may post the letters USP on their bottles, without the official seal they are not considered to be approved by the Convention. A list of products that have the USP Verified seal can be found on their website. In a similar fashion, another nonprofit agency called NSF International has a verification program for dietary supplements. NSF has an online database of supplements verified by their program; these supplements bear the NSF verification seal.

Look for these marks to ensure quality supplements

However, both the NSF and USP programs are voluntary – manufacturers can choose to participate in the program or not – and a detailed analysis of the products tested may not be made available. If you’re looking for information about the quality and composition of specific dietary supplements, there are additional online resources. Sites like provide an analysis of commercially-available supplements to determine if the product meets the claims on the label. Recommendations made by these sites are based on a variety of factors, including quality and cost of the supplement.

Unfortunately, the quality and content of over-the-counter supplements are not regulated by the US Food and Drug Administration (FDA), except when it comes to safety in the manufacturing process. The FDA does maintain a list of known contaminated and tainted products, but this does not extend to the purity or potency of active ingredients in your supplement.

The Linus Pauling Institute promotes eating a healthy diet as the primary source of micronutrients to keep you healthy. However, we recognize that sometimes supplements are necessary to prevent gaps between recommendations and the nutritional content of your diet. Together, the resources above should give you enough information to help you choose a dietary supplement that suits your needs. Other tips for choosing the right supplement can be found in the LPI’s Rx for Health.

Rx for Health

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“Don’t waste clean thinking on dirty data.”

For decades we have been trying to understand the effects of vitamin C on the immune system, especially since Linus Pauling wrote Vitamin C and the Common Cold in 1970, with only limited success. Our best and most comprehensive analysis of the data at hand, collected from decades of research studies, shows that vitamin C has very limited effects on the frequency and duration of the common cold in the general population. This has led many to conclude that taking vitamin C to ward off a cold just isn’t worth it.

Common Cold Vitamin C miniDoes this mean we can now close the book on vitamin C and colds? Far from it.

Hundreds of thousands of people, if not millions, take vitamin C to support their immune function. Anecdotal reports from around the globe have attested to the impact of vitamin C supplementation on health. Are people just fooling themselves? Why can’t the scientific evidence give us a definitive answer?

To put in bluntly: vitamin C studies have been a large mess of dirty data. Despite many decades trying to get it right, scientists still are doing a terrible job with vitamin C studies.

Vitamin C research has evolved very slowly over the 80 years since the vitamin was discovered. Scientists have yet to develop successful ways of studying many micronutrients, and vitamin C presents a special challenge due to the complexities of its biology and chemistry. Unfortunately, as we recently discussed in the Linus Pauling Institute Research Newsletter, this means that many of the published studies on vitamin C were not well designed and are hard to interpret. Trying to tie all those studies together is often impossible and definitive conclusions are few and far between.

Is it now time to rethink vitamin C from the ground up, especially with studies on the common cold? A restart, so to speak.

Where do we begin? Just like every new beginning, we need to learn from our past mistakes. Vitamin C researchers need to agree on essential criteria to measure the effect of vitamin C on the common cold. But even this seemingly simple step requires us to learn a great deal more about vitamin C’s role in the immune system.Orange Juice Vitamin C

Furthermore, we can turn to work with other vitamins and the immune system to provide a framework for future studies. For example, a recent analysis of vitamin D supplementation in the treatment of respiratory tract infections included studies only if they met very specific criteria that represent the best of nutritional science and our knowledge about the way vitamin D works in the body.

One of the most important criteria for a good study (and one of the main reasons that studies with vitamin C fall short) is to determine if taking a vitamin supplement actually increases vitamin levels in the body. People do not all respond to supplements the same way – there are variations in absorption and metabolism – and you can’t make any assumptions based simply on dose or its timing. Researchers must take the time to determine if their subjects could potentially benefit from a vitamin (by seeing it increase in their blood, for example) before actually determining if it had an effect.

To underscore the importance of vitamin C measurements as part of a research trial, we turn to a recent paper from Dr. Carol Johnston at Arizona State University. Dr Johnston and her colleagues recruited 28 healthy, non-smoking, young men and measured the vitamin C levels in their blood. Interestingly, despite eating (on average) food that contained the recommended intake values for vitamin C (~90 mg/day), these men showed vitamin C plasma levels in the low-normal range.

common cold nose blowAt the beginning of the study, half of the subjects were randomized to a group that received 1,000 mg of vitamin C each day, while the other half received an inert placebo pill. During the study, plasma levels of vitamin C were measured in each subject. Although it was not surprising – but still essential to confirm  – within four weeks vitamin C levels increased in the men taking the vitamin C supplements but not in those who took the placebo pill.

By the end of the eight-week study, fewer men taking the vitamin C supplements had colds versus those taking the placebo, suggesting that raising vitamin C levels in the body was very important in preventing a cold from developing. And although the result did not reach statistical significance, the men taking vitamin C who did have a cold had fewer days with symptoms – shortening their colds by about three days. Those taking vitamin C supplements were also more physically active, possibly because they were feeling better, but other possibilities exist; in particular, vitamin C has been shown to affect mood and energy metabolism.

This was a remarkable finding and perhaps a new beginning for research on vitamin C and the common cold. However, this study had a small number of subjects, so it will be interesting to see if comparable results are found in larger, yet equally well-designed studies.

If scientists learn from past mistakes and perform high-quality studies on micronutrients, the beneficial effects of vitamin C on the common cold may finally be elucidated as we begin to fully understand the ways this important vitamin impacts human health.

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vitamin EA surprising number of Americans fall short of micronutrient intake recommendations, as we have discussed in previous blog posts. While most of us are not suffering from rickets or pellagra (vitamin D and niacin deficiency diseases, respectively), many people may experience micronutrient ‘inadequacy’—insufficient intakes for optimum health.

Maret Traber with molecular model.It is hard to know if you have an inadequate diet. Often there is no telltale sign of an existing micronutrient inadequacy, as many have non-specific symptoms or no symptoms at all. Yet, the evidence suggests that these inadequacies may have very real and long-term consequences on our health and well-being.

As an example, we turn to Dr. Maret Traber’s new review on vitamin E inadequacy. Marginal vitamin E status is difficult to define, and its effects on neurological function are often subtle, in contrast to frank or severe vitamin E deficiency.

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Recent research at the Linus Pauling Institute has found that lipoic acid, a substance found in many plants and animals and also made in the body, modulates circadian rhythms in laboratory rodents. We realize that circadian rhythms aren’t something you hear about every day, so here is a primer on circadian rhythms and their importance.

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The Linus Pauling Institute has some very exciting research to report on potential therapies for amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig’s disease. Using a mouse model of ALS, Dr. Joseph Beckman (one of the leading researchers in this field, and a distinguished professor at the Linus Pauling Institute) and his colleagues in Australia and the United Kingdom have shown that a copper compound, called CuATSM, delayed the onset of symptoms and extended lifespan.

motor neuron

Put simply, this is potentially groundbreaking.

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Following nutrition news headlines in the last few months, its hard to escape a message that multivitamins are useless and that the science all points to these supplements being a complete waste of money (Guallar et al., “Enough Is Enough”).


This is simply not the case. In a recently published letter in Annals of Internal Medicine, nutrition experts from the Linus Pauling Institute at Oregon State University, the Children’s Hospital Oakland Research Institute, Tufts University, and the Harvard School of Public Health gather scientific evidence to show that the conclusions to stop your multivitamins are just plain wrong.

Want to see for yourself?

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In the last few months, stories from various news outlets (and even from different researchers at Oregon State University) have said:

This is confusing and frustrating for all of us. As is the case with most headlines, when you look more closely at the study details, explanations emerge. We have been gathering information on omega-3 fatty acids for decades and slowly learning about the many, varied, and complex effects of omega-3 fatty acids on health.

When you read the next news headline, consider these important issues:

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A report from the US Preventive Services Task Force (USPSTF) was published recently (February 25 issue) in the Annals of Internal Medicine. This report focused on the use of vitamin, mineral, or multivitamin supplements for the prevention of cardiovascular disease and cancer. The conclusions of the task force were largely that the current evidence is insufficient to assess the benefits and harms of most single-nutrient and multivitamin/mineral supplements with respect to prevention of cardiovascular disease and cancer, although they did issue caution for vitamin E and beta carotene supplements. For the most part, experts at the Linus Pauling Institute (LPI) at Oregon State University agree with these findings, and state they are supported by an evidence-based review of the scientific literature on vitamin and mineral supplements.

But do these conclusions mean you should stop taking your vitamins? Not in the slightest.Multivitamins2

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An article by Paul Offit titled “The Vitamin Myth: Why We Think We Need Supplements” has been part of the media blitz surrounding so-called negative claims of vitamin and mineral supplements.

Keep Taking Your Vitamins Blog Version

This article specifically takes excerpts from Offit’s recently published book “Do You Believe in Magic? The Sense and Nonsense of Alternative Medicine.”  The Linus Pauling Institute at Oregon State University has a different point of view – one that is based on the totality of the evidence, rather than selective claims:

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This week’s (December 16, 2013) headlines stated that adults should stop taking multivitamin/mineral supplements (what some refer to simply as a ‘multivitamin’) as they have no apparent health benefit and may potentially be harmful. We at the Linus Pauling Institute believe that these conclusions are wrong and ignore the totality of the evidence from decades of nutrition research. Continue reading

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