Media Coverage of Antioxidant Study - Lies, Damned Lies and Statistics!

Response from Quest Vitamins

Media Coverage of Antioxidant Study - Lies, Damned Lies and Statistics!

A rigorous assessment of the methodology of the original meta-analysis of vitamins by Bjelakovic et al; was carried out by Dr. Steve Hickey, Dr. Len Noriegai and Dr. Hilary Roberts (academics at Staffordshire University and Manchester Metropolitan University). This assessment uncovered the meta-analysis as being nothing more than basically lies, dammed lies and statistics!

Some of the main points made by Drs. Hickey, Noriegai and Roberts are listed below.
The statistics were inappropriately applied to poorly selected data, thus the conclusions are invalid.
Experimenter bias was compounded by a basic misuse of statistical testing.
Of the initial studies, 14,910 (93%) were discarded, with only a brief explanation of the exclusion criteria.
747 (92%) of the 815 were rejected, for example, because no subject died during the experiment. The remaining 68 studies were included in the analysis.
The large number of studies by Bjelakovic himself raises concerns in respect of objectivity, as the probability of trials being selected for inclusion in a meta-analysis can be influenced by knowledge of their results, leading to inclusion bias.
critical failing of the Bjelakovic paper is the absence of detail on the number of statistical tests performed on the data.

The fact that this many tests were carried out on just one of the supplements (vitamin A) investigated suggests the results of the study are unreliable. Conventionally, a single statistical test has a 1 in 20 probability of being significant by chance alone. With 100 such tests, we would therefore expect five 'significant' results, just by chance.

Media reports gave the impression that scientific evidence suggests vitamins may be harmful. In fact, no evidence has been provided to this effect. The statistics provided were insufficient to support a claim that vitamin supplements will increase mortality. Moreover, the results cannot validly be generalised to a relatively healthy general population

Bjelakovic's meta-analysis has little biological meaning, because of the large number of ill-defined substances that have been grouped together. The meta-analysis includes a diverse range of doses of the individual supplements, with no concern for the expected physiological effects.
A The authors, by not controlling for experimenter bias, have produced a paper that might simply reflect their own personal bias.

Do Antioxidants Increase Mortality?

Response From Quest Vitamins

DO ANTIOXIDANTS INCREASE MORTALITY? – ABSOLUTELY NOT!

In fact, antioxidants are a vital element of the daily diet, be it from food or supplements.
The media have been busy with sensational headlines that suggest "Treatment with beta carotene, vitamin A, and vitamin E may increase mortality." Do we now all stop taking our daily vitamin supplements? Before we do that, let's first examine this study.

"This is a flawed analysis...the totality of the evidence indicates that antioxidants from foods or supplements have many health benefits, including reduced risk for cardiovascular disease, some types of cancer, eye disease, and neurodegenerative disease...they are a key to an enhanced immune system and resistance to infection."

Dr. Jeffrey Blumberg, Director of the Antioxidants Research Laboratory at Tufts University in Boston, Massachusetts

First of all, the conclusions of this study were based entirely on a statistical review of selected old data. There was really no experimental design or actual study done here. Further, it was published by the same "scientists" that denounced antioxidants in a Lancet article in 2004. The latter was dismissed as science fiction by most credible scientists but the authors are back again with even more nonsense. They discount most of the well-established scientific support for antioxidants and go on to conclude that antioxidant vitamins increase death from all causes.

Wrong Dosages Evaluated
If one wants to see whether or not a nutrient is effective in preventing or curing illness one must at least use the correct dosage. The statistical review used suboptimal, very wide and inconsistent dosage ranges for the antioxidants evaluated.

Supplement Dose range
Vitamin A (synthetic) 1,333-200,000*** IU
Alpha Tocopherol (synthetic) 10-5,000 IU
Vitamin C (synthetic) 60 – 2,000 mg
Selenium (natural) 20 – 200 mcgWho in their right mind takes 200,000 IU of vitamin A for 3 months of time on their own? The way this review is put together one would assume that everyone does this and ends up poisoning himself or herself.

Poor Selection of the Study Population for Too Short Duration
The studies selected for review used an average age of 62 for their subjects for an average of 3.3 years. No one in their right mind could possibly hope that the use of selected antioxidants could somehow be beneficial in prolonging life in those that had already endured a lifetime of oxidative damage.

In other words, giving 60 year old plus smokers who had been taking at least 3 or more drugs some antioxidants is like using petrol to put out a fire. Yet, this is similar to what these authors did.

Overwhelming Antioxidant Safety and Efficacy Studies Ignored
Several hundred studies published in peer reviewed medical journals have used large populations of individuals studied for decades (not 3.3 years) and concluded highly significant life extending benefits of antioxidant supplements.