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From The June 2000 Issue of Nutrition Science News
Nutrition Q&A
with Dan Lukaczer, N.D.
Calcium vs. Cancer
Q: Can calcium prevent colon cancer?
A: There certainly appears to be a connection between calcium consumption and low colon cancer risk. Extensive epidemiological evidence suggests that low intake of calcium, along with small amounts of fiber, increases colon cancer risk.1 The theory is that individuals with high-fat diets have higher levels of toxic byproducts in the colon. Calcium and fiber help to bind up these toxins before they can damage colon wall cells.
A recent study conducted by researchers at the Department of Medicine, St Luke's/Roosevelt Hospital Center and Columbia University, both in New York, showed that in 70 patients, increasing dietary calcium intake to 1,200 mg/day resulted in significant improvement in colon cell health in subjects with a history of colon polyps.2 (Colon polyps are considered risk factors for colon cancer.)
A four-year study on more than 925 patients recently completed at Dartmouth-Hitchcock Medical Center in Lebanon, N.H., also showed benefit with the same dose of elemental calcium, although the benefits were only modest.3 Since it appears that the development of colon cancer can happen over decades, longer-term studies need to be conducted. However, because the risks associated with this level of calcium intake are minimal, and since there are various other benefits to calcium, individuals with a history of colon cancer in their family would be wise to get at least 1,200 mg/day.
An Herb for the Heart
Q: Does hawthorn cure congestive heart failure?
A: No, but hawthorn (Crataegus oxyacantha) may increase survival time and improve quality of life for those with congestive heart failure (CHF). A patient with CHF is unable to efficiently pump blood out of his heart. It is often the result of weak and dilated heart chambers. Congestion may occur in the lungs or the circulatory system and results in a variety of symptoms, most commonly shortness of breath and edema (fluid buildup and swelling). CHF is a difficult condition to treat because the heart progressively gives out—the five-year survival rate is less than 50 percent.
Hawthorn is thought to exert its effect by actually improving the micro-circulation in the heart itself. A number of studies have evaluated hawthorn's usefulness in treating CHF. The most impressive work I've seen is a cross-cultural European study in which more than 3,600 patients were treated three times/day with 300 mg of hawthorn standardized to 2.2 percent flavonoids. Although it was an observational study and not a placebo-controlled trial—researchers gave all patients the same treatment—the eight-week results were impressive nonetheless.
Heart palpitations were reduced from an average of 39.9 percent to 18.4 percent, edema dropped from 50 percent to 12.8 percent and overall symptom score was lowered from 9 to 2.6 on average during the course of the study. The authors note that hawthorn provided a significant overall benefit for patients being treated for CHF symptoms.4
Orange Blush
Q: A customer of mine has been juicing with carrots and recently complained of orange palms. What causes this and is it harmful?
A: The medical term for this condition is carotenemia. In this case, it is probably caused by the excessive consumption of carotene-rich foods. Carotenes are slowly converted to vitamin A in the body. Eating a lot of carotene-rich foods such as carrots (or taking a lot of beta-carotene supplements) overwhelms the body's conversion capabilities. The extra carotene is not converted to vitamin A and instead is stored, most often in the palms, soles and behind the ears.
This yellow hue to the skin can look like jaundice, which is a serious condition. Jaundice, however, can generally be differentiated because it turns the whites of the eyes (the sclera) yellow as well. Jaundice also has other symptoms such as fatigue and itchy skin.
Carotenemia can also occur in people with diabetes and hypothyroid disease (low thyroid function). Both of these conditions inhibit the conversion of carotene to vitamin A. Although it certainly sounds like your customer's condition is the result of eating lots of carrots, you may want to suggest that he see a doctor to rule out any more serious problems. Carotenemia is generally a benign condition that goes away a few months after carotene consumption is reduced.
In the past few years we've come to learn that the antioxidant activities of nutrients such as beta-carotene, vitamin C and vitamin E all work together. Therefore, excessive consumption of one without concurrent consumption of others may actually be problematic in some people. While I'll still occasionally prescribe single antioxidant nutrients for short durations, I'm much more likely to balance the intake with a broad-spectrum antioxidant formula.
Dan Lukaczer, N.D., is director of clinical services at the Functional Medicine Research Center, a division of HealthComm International Inc., in Gig Harbor, Wash.
References
1. Mobarhan S. Calcium and the colon: recent findings. Nutr Res 1999;57(4):124-9.
2. Holt P, et al. Modulation of abnormal colonic epithelial cell proliferation and differentiation by low-fat dairy foods. JAMA 1998;280:1074-9.
3. Baron J, et al. Calcium supplements for the prevention of colorectal adenomas. N Engl J Med 1999;Jan 14;340(2):101-7
4. Schmidt U, et al. High dose crataegus therapy in patients suffering from congestive heart failure NYHA class I and II. Z Phytotherapie 1998;19:22-30.
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