Research condemning vitamin supplements has several flaws

Research condemns vitamin supplements, but points out methodological flaws

By Blake Gossard, Kira Schmid, ND, Lucas Hube, ND, MBA, Steven V. Joyal, MD.

Source: Life Extension Foundation
Translated by: Essentia Pharma

“With serious methodological errors, two publications and an editorial in the December 17 edition of the magazine Annals of Internal Medicine have tried to discredit the value of vitamin supplements.¹-³

In one of the studies, participants were given multivitamins without quality assurance or in inadequate therapeutic doses. Adherence and drop-out rates were disappointing in all the studies. However, mainstream sources are using these flawed studies to condemn multivitamins.

The first study, which used low-dose vitamin supplementation, analyzed cognitive effects in elderly males² and, not surprisingly, the conclusions questioned the benefits of multivitamins for cognition. In the second study, individuals with a history of heart attacks had their cardiovascular risk parameters assessed and monitored for around 4.5 years, receiving either a multivitamin supplement or a placebo.¹

Despite flaws in the design and methodology, the study nevertheless revealed beneficial evidence in the association between multivitamins and cardiovascular risk. However, the researchers who developed the study ignored the findings that offered protection to the cardiovascular system, questioning the benefits of this type of treatment - misconceptions that are not being discussed in the media.

Topics related to the study of cognitive function

Inadequate criteria

Individuals who took the supplement for only 2/3 of the study period were included, i.e. even if they went 4 months during the year without supplementation, these participants would be part of the statistics.

Memory-based quiz

Once a year, participants were asked to report on their treatment. This approach, based on memory, tends to be biased, since more rigorous studies, among other methods, ask participants to bring the amount of unused product with them to be quantified.

Low dosage

The supplement used in the study had inadequate concentrations of nutrients, with only a small amount of vitamin C (60 mg), vitamin B12 (25 mcg) and selenium (20 mcg).

Health-seekers who are conscientious about nutritional needs for therapeutic purposes know that the above doses are unlikely to offer considerable health benefits, and the authors themselves point out that “doses of vitamins may be too low...”.

Cognitive benefits

After 2.5 years of low-dose treatment, there was an improvement in the cognitive function of the participants compared to the controls, although without statistical significance.

Nutrients X Cognitive Function

Vitamins B6, B12 and folic acid are important for methylation reactions and deficiency of these nutrients is associated with severe impairment of brain function.⁵ Men and women with mild cognitive impairment supplemented with vitamins B6, B12 and folic acid for 24 months were found to have 29% less brain atrophy and higher cognitive test scores, compared to those who received placebo.⁶
Several studies implicate oxidative stress in mild cognitive impairment and Alzheimer's disease,⁷-⁹ and antioxidant vitamins such as C, E and beta-carotene appear as brain protectors against oxidative damage.¹⁰

Evidence points to the actions of vitamin A on the physiology and behavior of the adult brain. One example is a vitamin A metabolite, retinoic acid, which signals the regulation of nerve cell and nerve growth, and synaptic plasticity.¹¹

In a double-blind, placebo-controlled study involving more than 200 healthy individuals aged 50 on average, they were randomly divided into two groups who received either vitamins or placebo and were then assessed for cognitive function. During the cognitive challenges proposed, those who ingested a greater amount of nutrients showed less fatigue, as well as being faster and more accurate in solving them.¹²

Another double-blind, control-placebo study, published in 2012 by Australian researchers, administered multivitamins to men aged 50 to 74 for 8 weeks. The authors noted that supplementation significantly improved some aspects of memory and concluded that “relatively short-term supplementation can prevent [...] risk factors for cognitive decline.”¹³

Topics related to the study of cardiovascular changes

Low adherence

When cardiovascular risk parameters were studied, 46% of the subjects dropped out of treatment during the study - a considerably high percentage. To generate an effective analysis, an acceptable number of participants must be used who follow the treatment from start to finish. For members of the Life Extension®, “...it is surprising that the editors of the Annals of Internal Medicine allowed this methodologically flawed research to be published.

We know that health benefits are not acquired casually or with intermittent treatments, but through a lifelong effort that requires quality and regular nutritional supplements.”

Study minimizes the effects of multivitamins

Two participants included in the study and supplemented had reduced cardiovascular events, although without statistical significance. This effect is usually greater when the duration of treatment is more than four and a half years. Despite concluding that multivitamins do not protect against cardiovascular changes, the researchers themselves found a reduction of 11% in their primary endpoint. In addition, there was a reduction of 18% in the secondary endpoint.

High confidence interval (CI)

An important part of a study design involves defining a range that considers the statistical results relevant or not. In this study, the authors projected a 25% reduction in cardiovascular risk. This means that for the treatment to be effective, the intervention would have to eliminate 1 in 4 outcomes for cardiovascular changes - a rate that is considered very high and which assumes that multivitamins would not provide any advantage from the outset.

Supplemented group had more diabetic patients

Diabetes mellitus is one of the strongest known risk factors for cardiovascular disease. It is therefore extremely important for any study to ensure that all participants have similar baseline glucose levels. If there are altered levels that are very different from each other, the group with a higher frequency of diabetes will have a higher cardiovascular risk.

Low doses of vitamins D and B12

Although the researchers referred to the multivitamin as “very effective”, one of the most important components for heart health was practically absent from the formula.¹⁴ In the study, vitamin D was in a dosage of 100 IU. To maintain 25(OH)D levels between 50 and 80 ng/mL, the medical community currently advocates the daily use of 2000 IU of vitamin D a day.

The other nutrient that was not widely available was vitamin B12 (100 mcg). This is essential for reducing levels of the amino acid homocysteine in the bloodstream, which is associated with cardiovascular risk.¹⁵ Doctors consider that levels of between 300 and 600 mcg of vitamin B12 are necessary to maintain optimal homocysteine levels (8 μmol/L).¹⁶

The importance of gamma tocopherol overlooked

While the alpha-tocopherol form of vitamin E was included in the formula used in the study, the gamma-tocopherol form was not. Evidence shows that, in the absence of gamma-tocopherol, alpha-tocopherol may not provide significant cardiovascular protection, as well as reducing pre-existing gamma-tocopherol levels.

Editorial downplays the researched benefits of vitamins and minerals

Despite the opinions presented by the authors of the editorial, other research has shown that multivitamins protect against cancer and cardiovascular disease.²⁶,²⁷

Conclusion

Based on an analysis of these studies and existing research, the Life Extension® continues to recommend the supplementation of a high quality multivitamin, containing physiological doses of a wide range of vitamins and minerals, as well as higher doses of omega 3, vitamin D, curcumin, coenzyme Q10, PQQ, carnosine, lipoic acid, among other nutrients and hormones that play a crucial role in maintaining health.”

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