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From The November 2000 Issue of Nutrition Science News
Nutrition Q&A
with Dan Lukaczer, N.D.
Does Frequency Matter?
Q: A customer has been using an herbal extract called pygeum for benign prostatic hypertrophy (BPH). He takes it twice a day and says it seems to help. Can he just take it all at once?
A: The issues of how much to take of a particular herb, in what form, and the consistency or standardization of its constituents are important questions and are constantly being asked by patients and customers. The question of how often a botanical extract needs to be taken does not come up as frequently—but may be just as important. Pygeum (Pygeum africanum), an herbal extract from the bark of the African plum tree, is recommended, like the more well-known saw palmetto (Serenoa repens), for BPH. In studies, pygeum has compared favorably to saw palmetto.9
While some compounds need to be at a consistent, constant level in the bloodstream throughout the day to maintain or achieve their intended effect, others do not. With pygeum, a study conducted last year showed that taking 100 mg of the standardized extract once a day proved to be equally as efficacious as 50 mg twice a day.10 So in this case, the convenience of once-a-day dosing does not compromise its efficacy. However, this is not the case with all remedies (aspirin, for instance), and one should be sure before recommending this kind of convenience. It does no good to recommend the right medicine but with the wrong directions.
ALA Eases Diabetic Neuropathy Symptoms
Q: Is it true that alpha-lipoic acid may treat diabetic neuropathy?
A: Diabetic neuropathy (DN) is a frequent complication of diabetes and is caused by nerve damage from elevated blood-glucose levels. Numbness, tingling and unremitting pain in the feet and legs are the most common symptoms. Alpha-lipoic acid (ALA) has been investigated because of its antioxidant activity. ALA is a potent antioxidant that also regenerates other antioxidants such as vitamins C and E; it also raises intracellular glutathione levels.1 Thus far, 15 clinical trials have been completed with ALA in DN using different study designs, treatment duration, doses, sample sizes and patient populations. Generally, the results have been positive, with improvement of DN symptoms starting at doses of 600 mg/day,2 although oral dosages may have to be as high as 1,800 mg/day to show an effect.3 A long-term multicenter trial of oral treatment (NATHAN I Study) is being conducted in North America and Europe to clarify these earlier findings.
Weight Loss Woes
Q: What do I tell customers confused about the low fat/low carbohydrate issue for weight loss? Won't you lose weight just by eating fewer calories?
Weight loss is a confusing issue and is hotly debated—not only in the popular press but also in the research community. There are so many facets to why people gain weight and why they can or cannot lose it that it would take a book just to lay out all the issues.
I'll try to succinctly answer this issue of carbohydrates. Basically, all calories are not created equal and neither are all carbohydrates. In 1981, the term glycemic index (GI) was coined to describe the blood-sugar response following the ingestion of a standard amount of carbohydrate as measured against a standard test carbohydrate food.4 Some research has suggested that the higher the GI of the diet, the higher the risk for diabetes and its complications.5
But the GI of carbohydrates may be important for another reason. Because protein intake for most individuals remains within a fairly narrow range, reductions in dietary fat often recommended in weight-loss programs tend to cause a compensatory increase in carbohydrate consumption. Those carbohydrates are typically high on the GI (potatoes, refined flour products, bananas and sugar, to name a few). In fact, more than 80 percent of carbohydrates consumed by children ages 2 to 18 would have a GI rating equal to or greater than that of table sugar.6
Many studies have examined the effects of various foods on appetite and most have reached the same conclusion: the lower the GI of a food, the more satiated a person is, the longer the delay in hunger, and therefore the less a person eats.7Evidence suggests that these high-GI foods elicit higher insulin levels, calorie for calorie. These high insulin levels (hyperinsulinemia) result in weight gain by preferentially directing the body to store glucose (as fat) and inhibit fat breakdown for energy.8
Therefore, from a hormonal standpoint, all calories are not alike when it comes to carbohydrates. Of course this is but one aspect of the weight-loss story, but it is an important one. Maybe weight-loss programs should rely not so much on the percent of carbohydrates eaten as on the type of carbohydrates consumed.
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. Packer L, et al. Neuroprotection by the metabolic antioxidant alpha-lipoic acid. Free Radic Biol Med 1997;22(1-2):359-78.
2. Ziegler D, et. al. Alpha-lipoic acid in the treatment of diabetic polyneuropathy in Germany: current evidence from clinical trials. Exp Clin Endocrinol Diabetes 1999;107(7):421-30.
3. Ruhnau K, et al. Effects of 3-week oral treatment with the antioxidant thioctic acid (alpha-lipoic acid) in symptomatic diabetic polyneuropathy. Diabet Med 1999 Dec;16(12):1040-3.
4. Jenkins D, et al. Glycemic index of foods: a physiological basis for carbohydrate exchange. Am J Clin Nutr 1981;34:362-6.
5. Brand J, et al. Low glycemic index foods improve long-term glycemic control in NIDDM. Diabetes Care 1991;14:95-101.
6.Suber A, et al. Dietary sources of nutrients among U.S. children, 1989-1991. Pediatrics 1998;101:497-504.
7. Holt S, et al. Interrelationships among postprandial satiety, glucose and insulin responses and changes in subsequent food intake. Eur J Clin Nutr 1996;50:788-97.
8. Sigal R, et al. Acute postchallenge hyperinsulinemia predicts weight gain: a prospective study. Diabetes 1997;46:1025-9.
9.Breza J, et al. Efficacy and acceptability of tadenan (Pygeum africanum extract) in the treatment of benign prostatic hyperplasia (BPH): a multicentre trial in central Europe. Curr Med Res Opin 1998;14(3):127-39.
10. Chatelain C, et al. Comparison of once and twice daily dosage forms of Pygeum africanum extract in patients with benign prostatic hyperplasia: a randomized, double-blind study, with long-term open label extension. Urology 1999;54(3):473-8.
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