The Vitamin E-Beta Carotene Cancer Study in Finland
by Michael B. Schachter, M.D., F.A.C.A.M.

Recently, a now-famous beta carotene-cancer study from Finland
hit the front pages of many newspapers and magazines. The newspaper articles
warned that beta carotene might cause cancer and that people should not be so
willing to take nutritional supplements because they may be dangerous. These
newspaper reports and magazine articles were based on a study published in the
prestigious New England Journal of Medicine on April 14, 1994. The study was
entitled "The Effect of Vitamin E and Beta Carotene on the Incidence of
Lung Cancer and Other Cancers in Male Smokers." Although carried out in
Finland, the study was co-sponsored by the National Cancer Institute and paid
for largely with your tax dollars.
In this study, more than 29,000 middle-aged men, who smoked
over a pack a day for an average of 36 years each, were divided into four groups
and followed for five to eight years. One group received daily dosages of 20mg
(or 33,000 units) of synthetic beta carotene. A second group received 50mg of
synthetic vitamin E, in the form of dl-alpha tocopherol acetate. A third group
received both of these supplements. And, finally, a fourth group received a
placebo.
The results of the study indicated a significant 18% increase
in incidence of lung cancer in the participants receiving beta carotene.
Although, fewer cases of prostate cancer were diagnosed among those who received
vitamin E than those who did not, this point was not emphasized in the news
accounts.
What were the flaws in the study? There were many. The study
used only 1/8th to 1/40th the dosage of Vitamin E shown by more than 20 previous
studies to lower the risk of lung cancer in smokers. It used only 1/10th the
dosage of beta-carotene recommended by other experts for the prevention of lung
cancer in smokers. It used as subjects people from Finland despite the fact that
both the British Medical Journal and the American Journal of Clinical Nutrition
consider Finland one of the worst countries in the world for cancer/nutrition
studies since: (1) Finns have one of the world's highest rates of per capita
alcohol consumption by smokers, and alcohol interferes with the utilization of
Vitamin E and beta carotene, and (2) Finland has an extremely low level of the
essential mineral selenium in the soil, and selenium works together with vitamin
E in promoting cancer prevention.
A previous, much less publicized recent study, carried out in
China with National Cancer Institute cooperation, included 50 micrograms of
selenium, along with 30 mg of vitamin E and 15mg of beta carotene. This study
involved 30,000 people over the age of 40, who were either healthy or suffered
from the premalignant lesion, esophageal dysplasia. Those who received the
combination of these three nutrients had a significantly lower risk of dying
from cancer and other diseases.
Other criticisms of the study include the fact that the study
started immediately after the Chernobyl nuclear disaster, which occurred in
1986, and Finland was one of the first areas to receive heavy fallout. This
variable increases cancer risk and makes the jobs of these low levels of
antioxidants more difficult. The form of vitamin E was the less potent synthetic
dl-alpha tocopherol rather than the physiologic d-alpha tocopherol form. And all
of the supplements were colored with quiniline yellow, a substance with known
carcinogenic properties.
The authors themselves were careful to point out that no other
studies have ever shown any harm from taking beta carotene, whereas many studies
have shown beneficial effects. In addition, there are no known mechanisms for
toxic effects of beta carotene. There overall conclusion was: "In spite of
its formal statistical significance, therefore, this finding may well be due to
chance."
You would never know this from the media circus accounts of
the study. The universal message, received by many of my patients and the
general population, was that vitamins, particularly beta carotene, cause cancer.
I hope that this information clears up some of the confusion.
© 1996 Michael B. Schachter M.D.