From The October 2001 Issue of Nutrition Science News

At the Counter with Dan Lukaczer, N.D.

It's Nice To Share
Q: I take prescription medications as well as dietary supplements. Should I tell my doctor about the supplements I take?

A: Yes, I think you should, although you don't appear to be alone. Dietary supplements sales have jumped nearly 80 percent since 1994, with half of Americans taking supplements. However, a recent study revealed that most of those people do not discuss supplements use with their physicians.¹ Many do not discuss this issue because they believe their doctor knows little or nothing about these products and may be biased against them. One useful book for physicians and patients is the Drug-Induced Nutrient Depletion Handbook (Lexi-Corp, 2001).

Interestingly, the survey also revealed that the majority of Americans favor increased government regulation of dietary supplements. They want the U.S. Food and Drug Administration to review the safety of new dietary supplements prior to their sale; to remove products shown to be unsafe; and to increase the government's authority to ensure the validity of advertising claims. Consumer attitudes are changing as the population becomes more educated and, consequently, more demanding that they get what they pay for.

Get The Lead Out
Q: Is the lead found in hair-coloring agents absorbed in the body, and, if so, is it toxic?

A: There's no question that lead is a toxic metal, even in minute amounts. Lead is dangerous when inhaled or ingested. I do not believe there is significant lead absorption from hair-coloring agents, and I am not aware of any studies that evaluate increased lead toxicity in people who use them.

At the same time, it is important to remember that lead toxicity is subtle, and the level at which exposure is safe is unknown. In fact, the federal government has consistently lowered the acceptable limit over the past few years as researchers discover that lower concentrations than they had originally thought cause subtle neurological deficits. For instance, very low levels of lead exposure can be a source of learning disabilities in children.

Hair analysis can often be useful in assessing levels of toxic elements absorbed from the environment. However, I would not recommend a hair analysis for people who color their hair because it would result in a false-positive reading. That is, the lead in hair color, which then is bound onto hair, would skew the results upward and would not be a good indication of how much lead is being absorbed. I don't think a serum analysis is useful either because serum levels generally measure acute exposure. In this case, lead toxicity may be evaluated using pubic hair, but this should be discussed with a reliable research laboratory staff.

Fiber May Protect The Colon
Q: I have a family history of colon cancer, and I am confused by the conflicting news stories about fiber intake. What is your opinion?

A: Colon cancer ranks among the top three forms of cancer in the United States, for both men and women. Prevention is the key, and researchers have attempted to clarify what nutritional and dietary habits are most important. Fiber has long been thought to act as a preventive agent against colon cancer, but some recent studies show no protective effect, or worse, possibly a negative effect as a result of certain fiber supplements.^2,3 However, initial results from the largest study of diet and health ever undertaken, the European Prospective Investigation of Cancer (EPIC) study, indicates that dietary fiber provides strong protective effects against colon and rectal cancers.4 EPIC involves more than half a million people in 10 European countries. It is expected to produce much more detailed information about the effect of diet on long-term health than previous studies. EPIC data on the relationship between fiber and colon cancer are not yet published, but have been reported at medical conferences.

Fiber supplements are generally safe, but we need to continue monitoring research to ensure supplements' safety. While the scientific debate continues, people need to make decisions now. Although this is a confuing research topic, it seems to me that there is much to gain and little to lose by eating more fiber-rich foods. We often forget Hippocrates' dictum, "let food be your medicine," in our haste to pop a pill or supplement. Increasing fiber intake through foods, however, has little downside. Increasing dietary fiber may not provide a complete solution for colon cancer prevention, but it is clear that a high dietary fiber intake is a good start and offers numerous other benefits as well.

Dan Lukaczer, N.D., is director of clinical research at the Functional Medicine Research Center, a division of Metagenics Inc., in Gig Harbor, Wash.

References

1. Blendon RJ, et al. Americans' views on the use and regulation of dietary supplements. Arch Intern Med 2001;161(6):805-10.

2. Alberts DS, et al. Lack of effect of a high-fiber cereal supplement on the recurrence of colorectal adenomas. N Engl J Med 2000;342;1156-62.

3. Bonithon-Kopp C, et al. Calcium and fibre supplementation in prevention of colorectal adenoma recurrence: a randomised intervention trial. Lancet 2000;356:1300-6.

4. Bingham S, et al. Plant polysaccharides, meat and colorectal cancer. European Conference on Nutrition and Cancer; 2001 Jun 21-24; Lyon, France. [Abstract # 0.21].