Education and debate

Validity of advertising claims for multivitamin preparation Vitacor 20/90 on the internet

Uwe Tröger, resident in clinical pharmacology,  Frank P Meyer, professor of clinical pharmacology. 

Institute of Clinical Pharmacology, Otto-von-Guericke University, University Hospital, Leipziger Strasse 44, 39120 Magdeburg, Germany

Correspondence to: Dr Tröger uwe.troeger{at}medizin.uni-magdeburg.de

New electronic media such as the internet offer great possibilities for spreading serious medical information from healthcare professionals, organisations, and authorities to the public. However, there is also a reverse side to this coin. Some companies misuse the new medium for uncontrolled distribution of drugs that have not been tested properly by national authorities or medical societies. These companies deceive patients in their advertising messages. By using citations from serious medical journals, they lead people to believe that their drugs are "highly effective." In addition, use of such drugs may encourage patients to abstain from the usual drugs administered by doctors.

In response to a patient's question about the usefulness of a multivitamin preparation in preventing and treating some cardiovascular diseases, we evaluated some of the claims made about Vitacor 20/90, which is being advertised intensively on the internet by Health Now (San Francisco, California, USA, http://www.healthnow1.com) and is distributed in Germany from the Netherlands.

	Product details

Vitacor 20/90 consists of 35 components (see box on next page for details). This information was available only by buying the product, as the company did not provide product information without a purchase. The bottle label stated that a daily dose of three tablets was suitable for everyone aged 20-90 years; suggested that it was useful for preventing and, as an adjunct, treatment of coronary heart disease, high blood pressure, irregular heart beat, heart failure, and diabetes; and that Vitacor had been clinically tested. We wished to test the validity of these claims since use of this product could have considerable financial and health risks. Daily use of the preparation for a year would cost an individual $350 (£234) for tablets and $475 (£316) for the drink mix.

	Proof of advertising statements in scientific literature

To support its advertising statements, Health Now offers on the internet on request a list of 40 references: "Clinical studies on nutrients in heart disease, a reference list." Assuming that, in its own interest, Health Now would cite cogent papers, we examined the listed studies. As Health Now is closely connected with the name of Mathias Rath, we also carried out a literature search for "Rath-M" in Medline and Embase Drugs. Independently of this, we examined key clinical studies on this topic. In our evaluation we limited ourselves to cardiovascular diseases, vitamins C, E ( tocopherol), the combination of vitamin C and vitamin A ( carotene), and clinical studies.

The papers by M Rath, L Pauling, and colleagues were either of hypothetical nature or they described animal experiments or surrogate criteria and are thus not considered here. Some of their texts were even identified as "advertisements." The single clinical test performed by the distributor of the product does not meet the quality criteria for controlled clinical studies in evidence based medicine.¹ Notably, the daily dose used in the test was three times higher than the recommended daily dose printed on the bottle.

Most of the 40 references offered by Health Now either investigated the influence of vitamins, etc, on surrogate criteria or the papers were only overviews. The results of the eight clinical studies that were of interest are compared with the company's advertising statements in the table. Certain pathological situations, such as obesity, can be connected with reduced plasma concentrations of  tocopherol and  carotene, which is seen as an additional cause of increased cardiovascular risk in obese people.¹⁰ However, no general clinical benefit of vitamins C and E and carotene can be proved from the works cited by Health Now.

	Current knowledge of benefits of vitamins for cardiovascular diseases

More recent works provide comparatively negative results. Vitamin A, retinol, carotenoids, and vitamin C did not reduce mortality from coronary heart disease in postmenopausal women.¹¹ Vitamin E, however, did have some beneficial effects at medium doses (8-12 IU/day), but higher doses (>12 IU/day) increased the risk again.¹¹ Health Now recommends 200 IU/day. Authors who could deduce from epidemiological investigations potential benefits from higher doses of vitamins C and E explicitly state the need for further intervention studies. ^{4 5 8}

In the case of patients at high risk of cardiovascular disease (men aged 50-69 who smoked and who had already had a heart attack) the risk of dying from heart disease was clearly increased by vitamin E and  carotene, both alone and in combination, when compared with placebo.¹² In another placebo controlled study  carotene (50 mg on alternate days) taken over 12 years did not protect 22 071 male doctors aged 40-84 against cardiovascular disease or against death from such disease.¹³ The combination of  carotene (30 mg/day) and vitamin A (25 000 IU/day) even led to an increased risk of dying from cardiovascular disease compared with placebo (odds ratio 1.26 (95% confidence interval 0.99 to 1.61)).¹⁴ As the patients receiving vitamins also died more frequently from lung cancer, the study was ended prematurely. Multivitamins ( carotene, vitamin C, and vitamin E) had no significant effect on the rate of angiographic restenosis or on major clinical endpoints such as death, myocardial infarction, coronary artery bypass grafting, and percutaneous transluminal coronary angioplasty.¹⁵

In summary it can be said that, although some epidemiological studies suggest that the intake of vitamins reduces the risk of getting or dying from cardiovascular diseases, these results are inconsistent. Intervention studies demonstrate no benefit from vitamin A, vitamin E, or  carotene. In certain situations the patients taking the vitamins are at greater risk than those taking placebo. There is still a lack of prospective, double blind, randomised, controlled clinical trials of vitamin combinations. Some are in progress now. One of the largest will be the Oxford heart protection study, with 20 000 subjects receiving a cocktail of vitamin E, vitamin C, and  carotene or placebo over five years.

	Conclusions

The uncontrolled advertising of drugs and nutritional supplements in electronic media such as the internet poses new problems for drug regulation. The distribution of these products circumvents national laws and authorities, and substances are circulated that have never been checked for effectiveness and safety. Furthermore, it is impossible to ensure correct use of such products, as patients are likely to treat themselves without consulting a doctor. In broad terms, this situation will probably lead to an increased incidence of individual damage to health.

The statement by the chairman of the BMA's general practice prescribing subcommittee, Dr Peter Fellows, that "People who have access to the internet are likely to be more intelligent and better off and not so easily duped by duff advertising"¹⁶ seems to have become obsolete. After all, it was a normal patient who asked us for detailed information about Vitacor, and who reported that the drug was introduced to her by her relatives and acquaintances, who were all enthusiastic users of this mixture. An effective mechanism to control medical advertisements in electronic media such as the internet can be established only on an international basis.

	Acknowledgments

Funding: None.

Conflict of interest: None.

	References

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(Accepted 19 June 1998)