From The June 2001 Issue of Nutrition Science News

At The Counter

With Dan Lukaczer, N.D.

Artichokes As Powerful Medicine
Q: Can artichoke heart extract lower cholesterol levels?

A: Not only is the artichoke (Cynara scolymus L.) a delicious vegetable, but its leaves contain phytonutrients with numerous health-enhancing effects. Perhaps the most important overall effect is increased bile production, and because the body makes bile acids from cholesterol, increasing bile acid production decreases serum cholesterol levels.

Increasing bile acid secretions also aids digestion—one reason why artichokes have traditionally been used for indigestion and dyspepsia.

Although the research on artichoke's ability to lower cholesterol is not all positive, the most recent and largest trial shows promise. A German, multicenter, placebo-controlled, randomized trial analyzed the effect of 450 mg artichoke dry extract four times/day on 143 patients with initial total cholesterol levels greater than 280. After six weeks, those taking the artichoke extract showed an 18.5 percent reduction in cholesterol, compared with 5.6 percent reduction in the placebo group.¹

Artichokes contain the phytonutrient cynarin (1,5-dicaffeylquinic acid). This is probably not the only active ingredient, but it is wise to select products standardized to cynarin content. Artichoke extract also has been shown in animal studies to have a marked antioxidant effect.²

Oily Advice For Pregnant Women
Q: Is it beneficial for pregnant women to eat fish?

A: Yes. It appears that in utero babies benefit from having their mothers consume fish. The benefits may be transferred during breast-feeding as well. A significant amount of research indicates breast-feeding at least four to six months is good for a baby. One of the reasons has to do with the kinds of fats that the baby is likely to get in breast milk.

Research suggests that certain fats are good for infants born prematurely. Docosahexaenoic acid (DHA), a fat from the omega-3 family, helps specifically with a preterm baby's eyesight. According to a recent article in the American Journal of Clinical Nutrition, full-term infants also benefit. This report suggested that healthy full-term infants who are breast-fed for at least four months show greater visual perception skills in early childhood than their bottle-fed counterparts.³ Researchers measured stereoacuity—a type of visual depth perception—in 435 three-and-a-half-year-olds. Breast-feeding for four months or more independently had the greatest positive effect on that visual skill. These researchers measured DHA in the mothers during pregnancy and concluded that those women with higher DHA levels, and who ate more fish, most closely corresponded with their children's improved visual skills.

This study supports the idea that even normal-term infants may develop improved visual acuity because they receive extra nourishment from DHA. Sources include fatty fish such as salmon, mackerel, sardines and tuna, fish oil or cod liver oil capsules and capsules containing an algae-derived vegetarian source of DHA.

Walk A Mile Further With Ginkgo Biloba
Q: My legs hurt when I walk, and I've been told I have 'intermittent claudication.' I've heard that the herb ginkgo can help me walk more comfortably. Is this true?

A: There's a reasonable chance that ginkgo (Ginkgo biloba) might help. Just as clogging of the arteries that supply the heart muscle can cut off oxygen flow and cause a heart attack, similar clogging in the leg arteries can damage the muscles there. This process is known as peripheral arterial insufficiency (PAI). The standard medical approach often includes taking prescription medications, such as pentoxifyline or cilostazol. Although these drugs may reduce symptoms and improve walking distance, they can also cause side effects such as headache, diarrhea, abnormal stools, dizziness and irregular heartbeat.

It is known that ginkgo helps blood flow in the brain, and a few studies in the past 10 years have suggested it might work in PAI. In one meta-analysis—a careful review of eight studies in which ginkgo was used to treat PAI symptoms—the authors concluded that the research showed a significant increase in pain-free walking distance in patients using ginkgo. While they described the herb's overall benefit as "modest," the improvement appeared to be comparable to that achieved with pentoxifyline.⁴ The usual dosage of a standardized ginkgo extract is 120 to 160 mg/day, divided in three doses. Using it for at least one month is a reasonable time period to expect results.

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. Englisch W, et al. Efficacy of artichoke dry extract in patients with hyperlipoproteinemia. Arzneimittelforschung 2000;50(3):260-5.

2. Gebhardt R. Antioxidative and protective properties of extracts from leaves of the artichoke (Cynara scolymus L.) against hydroperoxide-induced oxidative stress in cultured rat hepatocytes. Toxicol Appl Pharmacol 1997;144(2):279-86.

3. Williams C, et al. Stereoacuity at age 3.5 y in children born full-term is associated with prenatal and postnatal dietary factors: a report from a population-based cohort study. Am J Clin Nutr 2001;73(2):316-22.

4. Pittler MH, Ernst E. Ginkgo biloba extract for the treatment of intermittent claudication: a meta-analysis of randomized trials. Am J Med 2000;108(4):276-81.