No Cardiovascular Health Benefits Result from Most Common Dietary Supplements

It is well known within the research community that dietary supplements as a class achieve next to nothing for basically healthy people, those lacking any specific deficiency or medical condition that might cause that deficiency. In fact the evidence strongly suggests that some supplements, antioxidants for example, may even be modestly harmful over the long term. This scientific consensus has to compete with the marketing budget of the supplement industry, which seems to be doing fairly well for a community focused on selling a mix of largely useless and mildly harmful products. So studies such as this one continue to roll out, and perhaps one day there will be meaningful change as a result, but I'm not holding my breath.

Treatment and prevention of micronutrient deficiencies with vitamins and minerals in the last two-and-a-half centuries are among the most dramatic achievements in the history of nutritional science. However, interest in micronutrients has shifted recently from prevention of classic deficiency states to prevention of possible subclinical deficiencies and promotion of overall health and longevity using supplemental vitamins and minerals (supplement use). Here, the data are less clear, but supplement use is widespread.

Using the National Health and Nutrition Examination Survey data (1999 to 2012) on 37,958 adults, it was estimated that supplement use was high in 2012, with up to 52% of the population taking supplements. Multivitamins were taken by 31% of the population, vitamin D by 19%, calcium by 14%, and vitamin C by 12%. Despite high supplement use by the general public, there is no general agreement on whether individual vitamins and minerals or their combinations should be taken as supplements for cardiovascular disease (CVD) prevention or treatment.

We conducted a systematic review and meta-analysis of existing systematic reviews and meta-analyses and single randomized controlled trials (RCTs) published in English from 2012 to 2017. Where both supplements and dietary intakes of nutrients in foods were combined as total intakes, data were not used unless supplement data were also presented separately. We assessed those supplements previously reported on by the US Preventive Services Task Force (USPSTF): vitamins A, B1, B2, B3 (niacin), B6, B9 (folic acid), C, D, and E, as well as β-carotene, calcium, iron, zinc, magnesium, and selenium.

The following supplements were associated with no significant effect on CVD outcomes and all-cause mortality: vitamins A, B6, and E; β-carotene; zinc; iron; magnesium; selenium; and multivitamins. In general, the data on the popular supplements (multivitamins, vitamin D, calcium, and vitamin C) show no consistent benefit for the prevention of CVD, myocardial infarction, or stroke, nor was there a benefit for all-cause mortality to support their continued use. At the same time, folic acid alone and B-vitamins with folic acid, B6, and B12 reduced stroke, whereas niacin and antioxidants were associated with an increased risk of all-cause mortality. Overall, the effects were small; the convincing lack of benefit of vitamin D on all-cause mortality is probably the reason for the lack of further studies published since 2013. The effects of folic acid in reducing stroke is also convincing, with a 20% reduction.



On July 12th 2018, New York City, the Life Extension Advocacy Foundation will host a one-day event focused on aging research and biotech investment. Industry experts will share their knowledge of advances poised to revolutionize medicine. Well, I say the very best of luck to y'all and hoping that this event will prove productive and very worthwhile. I will be looking forward to seeing the results in the coming news events. Again, best wishes in that effort.

Posted by: John W. Sullivan at May 30th, 2018 8:19 AM

OK. There is no general agreement on the benefits of supplements/nutriceuticals. Many may be hoping they will compensate for an otherwise crappy lifestyle and diet. I think we need to be cautious that big pharma has been running a war against supplements, because they don't like the competition. Note that this study focuses largely on "chemical" supplements rather than herbals and did not mention probiotics.

Specifically regarding "antioxidants". The history goes back to 17th century English sailors being saved from scurvy by native Americans by pine bark tea. There is a general hazardous background of poison that is increasing in our environment; chlorine, heavy metals, atrazine, and plastics that damage the endocrine system. I suggest that none of these studies had a static control group. Ask yourself: Why was breast cancer extremely rare in Brazil 50 years ago, and now they have rates as high as the USA?

Posted by: Tom Schaefer at May 30th, 2018 8:37 AM

Title is a sweeping generalization in terms of the conclusion here. There's also a lot of evidence contradicting the conclusion about D on its own. Also is it D3? How was it taken? How much? What about hydroxyvitamin-D instead of D3? Why lump D in with multivitamins? Why lump any of them together this way instead of testing each one individually? Multivitamins are notorious for poor quality ingredients and plus, some of the other ingredients may have confounding effects that negate any positive benefits of one or another.

Posted by: Nathan at May 30th, 2018 9:24 AM

I don't take any vitamins except for Vitamin D and K2. Does this mean that they are worthless to take?

Posted by: DdR at May 30th, 2018 9:48 AM

A lot of denial and wishfull thinking in the comments. The study clearly shows that most supplements don't have any effect, and for those that have an (either beneficial or detrimental) effect, it's small.

Posted by: Antonio at May 30th, 2018 10:37 AM

I believe I made some valid criticisms and asked valid questions, no wishful thinking here.

Posted by: Nathan at May 30th, 2018 10:48 AM

I will agree with Nathan. And there are a lot next generation supplements that are not strictly vitamins. And maybe they were just not taking enough Zn, Mg, whatever. FWIW it is better to take methyl folate than folic acid as a lot of people are deficient in the conversion enzyme

Posted by: JohnD at May 30th, 2018 11:19 AM

It all depends on the specific supplement

Posted by: Scott e at May 30th, 2018 2:17 PM

Vit D3 is just a proxy for living outside in full spectrum sunlight, inhaling oxidized terpenes from plants, meeting friends, moving around using muscles etc.

Posted by: arren brandt at May 31st, 2018 1:00 AM

I would expect to have at least some placebo effect. And usually people taking eye supplements are marginally more health conscious s over the average. That means that the supplements stupid be slightly harmful to combat those two effects.

Posted by: Cuberat at May 31st, 2018 4:20 AM

However, folic acid alone and B-vitamins with folic acid, B6, and B12 reduced stroke risk factor. The rest do not appear to be useful and antioxidants are a bad idea in general due to the important role of reactive species in redox signaling.

Posted by: Steve Hill at May 31st, 2018 4:53 AM

Another supplement that is documented as being useful is glucosamine, this has been shown to reduce all-cause mortality and cancer mortality risk factors. Most supplements are likely useless junk but not all, and one has to read the literature to understand the difference. Saying all supplements are useful, or that all supplements are useless is wishful thinking and shows a distinct lack of understanding of how biology works.

Posted by: Steve Hill at May 31st, 2018 4:56 AM

For anyone actually interested in the data and not sticking to entrenched ideas, here are some interesting glucosamine studies that show reduced mortality from various sources:

Bell, G. A., Kantor, E. D., Lampe, J. W., Shen, D. D., & White, E. (2012). Use of glucosamine and chondroitin in relation to mortality. European journal of epidemiology, 27(8), 593-603.

Pocobelli, G., Kristal, A. R., Patterson, R. E., Potter, J. D., Lampe, J. W., Kolar, A., … & White, E. (2010). Total mortality risk in relation to use of less-common dietary supplements. The American journal of clinical nutrition, ajcn-28639.

Posted by: Steve Hill at May 31st, 2018 5:01 AM

Those studies prompted me to start taking glucosamine though I did not have an idea as to the mechanism; Reason posted on an interview with Michael Ristow wherein he discusses a possible mechanism:

It's cheap and seems quite safe, but I would not take more than the recommended dose:

I mostly try to get micronutrients from foods sources, though it is difficult to meet the RDA for some things. Foods that are especially helpful in ticking the boxes are: broccoli (esp. sprouts), cauliflower, spinach, kale, sweet potatoes, lentils, soy (tofu, natto, tempeh), black beans, mushrooms, almonds, bell peppers & berries. Of course, there are also a lot of food constituents that have health benefits that are not classed as vitamins or minerals.

Posted by: CD at May 31st, 2018 11:28 AM

Yeah, glucosamine seems to be useful, which is a rarity in supplements. The mortality data is fairly compelling for it and given it's cheap, it is something I take in the recommended dosage.

Posted by: Steve Hill at May 31st, 2018 6:04 PM

Dr. Mercola refuted all the claims in the article that supplements are useless in and article in his health column today. You should go to his cite and read the article to get a more enlightened view of the subject.

Posted by: Biotechy Marcks at June 3rd, 2018 7:53 AM

Mercola lol

Posted by: Steve Hill at June 4th, 2018 1:57 PM

This is such an poor study. It starts with the equivalent of, "It's a well known fact..", and concludes with an admonition to eat healthy foods and stay away from supplements. Wow! It isn't necessary to read any further, but if you skip to the end to see who funded this so-far-removed from reality meta analysis of meta analyses - voila - the trusted names in science: Coca Cola, Kellogg, Quaker Oats, Proctor and Gamble, Unilever, along with a host of agriculture associations.

Posted by: Noel Quinn at June 5th, 2018 1:01 PM

So true Noel, and you forgot Bayer, LoL! Is it any wonder that mainstream media conglomerates jump all over these flawed studies because of the fact that all of these corporations make up the bulk of their advertising revenue! I was going to write a detailed rebuttal to this but suffice to say anyone reading this website should be able to see the blatant problems with it.

Posted by: Eric at June 10th, 2018 10:46 AM

For those trained in the evaluation and interpretation of meta-analyses, it is useful to read the original study. I would not give the above summary high marks for objectivity but the study itself was perhaps most instructive for the generalizations and trends that it did not observe. A number of limitations apply to this kind of study and this study in particular. One weakness of these kinds of studies is that the dependent variables (e.g., antioxidants) have a materially different meaning in each of the primary studies. Therefore, when one makes a claim about the impact of antioxidants, the force of the claim rests on many different studies using many different antioxidants, on many different populations, under many different conditions, and for many different spans of time. Another restriction in the utility of the study goes to the impact time span when compared with the progression of CVD toward an observable event. For those looking for social bias, I note the dominance of Canadian researchers who carry out their work in a strongly anti-supplement culture. Such biases can manifest themselves in subtle ways. I see potential evidence of such bias in some of the wording of the findings. I also find that some of the citations to individual studies actually show positive benefits. For example, the randomized clinical trial to investigate the efficacy of an oral antioxidant micronutrient mixture to slow progression of age-related cataract showed a modest but highly statistically significant result.

In the end, take this study with an interpretative grain of salt in the same way that most positively or negatively trending studies should be taken. Look instead for general trends in a large number of studies, especially well-structured and controlled individual studies that do not set out to prove a point one way or another. Also look for small and well-defined case controlled studies that show dramatic results. Breakthroughs sometimes occur in this fashion.

Posted by: Robert W Tucker at October 12th, 2018 6:25 PM

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