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From The May 2001 Issue of Nutrition Science News
At the Counter with Dan Lukaczer, N.D.
Fish Benefits, Sans Fish
Q: A customer wants the benefits of good fats in fish but doesn't eat fish. What should she supplement with?
A: That's a somewhat complicated question to answer because it depends on why she's taking it. Many Americans get insufficient amounts of the healthy omega-3 fats found abundantly in cold-water fish such as mackerel, salmon, trout, and tuna. I often recommend omega-3 supplements to patients with a condition that could stem from a lack of these beneficial fats, such as arthritis, colitis, asthma, eczema, or psoriasis. Many authorities believe the American diet has an imbalanced dietary intake ratio of omega-6 to omega-3 fats, which may contribute to a host of health issues.
A maintenance-dose-range recommendation comes from a report published this year in the Journal of the American Medical Association.1 Researchers at Brigham and Women's Hospital in Boston tracked for 14 years the dietary habits and subsequent health problems of 80,000 women. They estimated that women who regularly ate fish rich in omega-3 oils significantly cut their stroke risk. In fact, women who consumed the most omega-3 fats had a 28 percent reduced likelihood of suffering a stroke. Those women said they ate fish two to four times a week. The average amount of the important fats eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in a serving of cold-water fish is about 300 mg and 200 mg, respectively. Therefore, it seems reasonable that women who don't like fish may want to take capsules totaling about 180 mg/day EPA and 120 mg/day DHA—a common capsule amount—to achieve that type of protection. Men would need somewhat higher levels because they are bigger.
Grapefruit Juice's Drug Interactions
Q: Can grapefruit juice interfere with the actions of prescription drugs?
A: Grapefruit juice is a nutritious drink, rich in vitamin C. It also contains a flavonoid called naringinin, which appears to have a pronounced effect on an enzyme called cytochrome P450 (CYP) 3A4. Found primarily in the liver and digestive tract lining, this enzyme is the key to breaking down and flushing out various drugs. If it is inhibited or blocked, then drugs that are usually broken down are instead retained and have a longer and stronger effect. This can be either good or bad.
For instance, cyclosporin A (CsA) is an immunosuppressant drug used to prevent transplanted organs from being rejected. Grapefruit juice has been investigated as a possible adjunct to CsA dosing in adult renal transplant recipients.2 It is possible that consuming grapefruit juice with CsA may essentially lower the dosage of this expensive drug.
The flip side is drug toxicity. A recent study showed that grapefruit juice dramatically decreased the metabolism of amiodarone, an antiarrythmic drug. 3 Many other drugs, including the antifungal agents fluconazole, itraconazole, and ketoconazole, are also (CYP) 3A4 inhibitors. Grapefruit juice's effect on herbal supplements is unknown. The bottom line is that we should treat grapefruit juice cautiously, particularly with patients on prescription medications.
The Skinny on Echinacea
Q: Can you get side effects with echinacea?
A: Any supplement or drug can have side effects. Recently there was a report of a single-case study of a reaction that resulted in erythema nodosum. In this case report, a 41-year-old man developed four episodes of erythema nodosum after taking echinacea.
Erythema nodosum is a condition characterized by tender, reddened nodules, usually on the front of the legs. It may be caused by or associated with infections such as streptococcus, tuberculosis, and hepatitis B. Sensitivity and subsequent exposure to drugs such as barbiturates, penicillin, and sulfonamides can also cause the reaction. In this case, the nodules appeared when the man took echinacea for flu symptoms. The patient was advised to discontinue echinacea. At one-year follow-up, he reported no recurrences.
The authors propose that echinacea may have "potentiated a susceptible patient's immune response, culminating in the development of erythema nodosum." They note atopic patients may be at an increased risk for severe allergic reactions because of the cross-sensitivity between echinacea and structurally similar allergens. They conclude, "as independent use of herbal therapies continues to grow, physicians must be aware of the potential medication interactions associated with this practice."
Echinacea has hundreds of years of historical use and is generally regarded as a safe herb with few side effects. Contraindications reported in the German Commission E Monographs include progressive systemic diseases such as tuberculosis and multiple sclerosis, and side effects include possible allergic reactions. This well-documented case study is duly noted, but should not signal alarm, decreased use, or decreased advocacy of this herb for treating minor infections.
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. Iso H, et al. Intake of fish and omega-3 fatty acids and risk of stroke in women. JAMA 2001;285(3):304-12.
2. Min DI, et al. Effect of grapefruit juice on cyclosporine pharmacokinetics in renal transplant patients. Transplantation 1996 Jul 15;62(1):123-5.
3. Libersa CC, et al. Dramatic inhibition of amiodarone metabolism induced by grapefruit juice. Br J Clin Pharmacol 2000 Apr;49(4):373-8.
4. Lee Soon S, Crawford RI. Recurrent erythema nodosum associated with echinacea herbal therapy. J Am Acad Dermatol 2001;44:298-9.
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