Emerging Alternative Therapies for Type 2 Diabetes ~ 10th Sept 2002
-Ginseng has been used in Chinese traditional medicine for 3,000 years and
is currently very popular as a dietary supplement. While health claims for
ginseng include curative, aphrodisiac, and restorative properties, few human
studies have been done to test these claims. In vitro and animal studies
have suggested that ginseng may have therapeutic effects on diabetes;
ginseng has lowered blood glucose in rodents. The only long-term human study
of ginseng and diabetes found that long-term glycemic control improved with
ginseng supplementation (200 mg ginseng extract/day for 8 weeks). However,
the type of ginseng extract was not specified and the results may have been
confounded because the subjects also experienced significant weight loss.
The authors tested the effects of American ginseng (Panax quinquefolius) on
postprandial glucose metabolism in persons with and without type 2 diabetes.
The ginseng was given in doses ranging from I to nine grams before an oral
glucose challenge. In the diabetics, doses of three, six, and nine grams
were equally effective in lowering postprandial glucose, which was 15-20%
lower compared with placebo. The safety profile was very good, and the data
suggest that ginseng might effectively augment conventional treatment for
type 2 diabetes.
The authors also conducted a long-term, placebo-controlled, double blind,
crossover study with 24 type 2 diabetics. The patients were randomly
assigned to take either placebo or one gram standardized American ginseng
extract before meals (three times/day) for eight weeks. Significant
reductions in fasting blood glucose and hemoglobin A1c (an indicator of
long-term glycemic control) occurred when patients took the ginseng. Blood
pressure also dropped during ginseng treatment; this was unexpected, as many
previous studies linked ginseng to increased blood pressure. The authors
concluded, "That an American ginseng extract added to the conventional
treatment of diabetes significantly improved glycemic and blood pressure
control beyond conventional treatment alone."
These preliminary data suggest that both konjac-mannan and American ginseng
offer promise in the treatment of type 2 diabetes. The authors concluded,
"konjac-mannan and American Ginseng both target meal-related metabolic
excursions safely, with mechanisms that appear to be different but
complementary to each other." They cautioned, however, that interactions
with other treatments could occur, although studies have not found any such
interactions to date. They also warned readers that much more research is
needed before these supplements can be considered mainstream alternative
therapies.
-Christina Chase, MS, RD