American ginseng improves glycemia in individuals with normal glucose tolerance: effect of dose and time escalation.
OBJECTIVE
We studied the effect of escalating the dose and administration time of American ginseng (AG, Panax quinquefolius L.) in nondiabetic individuals to achieve further improvements in glucose tolerance seen previously when 3 g of AG was taken 40 minutes before a 25 g glucose challenge.


METHODS
Ten nondiabetic individuals (6M:4F; mean +/- STD: age = 41 +/- 13 years, BMI = 24.8 +/- 3.5 kg/m2, FBG = 4.5 +/- 0.1 mmol L(-1)) on 12 separate occasions, randomly received 0 (placebo), 3, 6 or 9 g of ground AG root at 40, 80, or 120 minutes before a 25 g oral glucose challenge. Capillary blood glucose was measured prior to ingestion of AG or placebo capsules and at 0, 15, 30, 45, 60 and 90 minutes from start of challenge.


RESULTS
Compared with the placebo, 3, 6 and 9 g of AG reduced (p<0.05) postprandial incremental glucose at 30, 45 and 60 minutes; also, 3 and 9 g of AG did so at 90 minutes. At 60 minutes, 9 g of AG reduced incremental postprandial glucose relative to 3 g of AG (p<0.05). All AG doses reduced (p<0.05) area under the incremental glucose curve (3 g, 26.6%; 6 g, 29.3%; 9 g, 38.5%). AG taken at different times did not have an additional influence on postprandial glycemia.


CONCLUSIONS
In nondiabetic individuals, 3, 6 or 9 g of AG taken 40, 80 or 120 minutes before a glucose challenge similarly improved glucose tolerance.
Vuksan
V
V
Department of Nutritional Sciences, Faculty of Medicine, University of Toronto and Clinical Nutrition and Risk Factor Modification Centre, St. Michael's Hospital, Ontario, Canada. v.vuksan@utoronto.ca
Stavro
M P
MP
Sievenpiper
J L
JL
Koo
V Y
VY
Wong
E
E
Beljan-Zdravkovic
U
U
Francis
T
T
Jenkins
A L
AL
Leiter
L A
LA
Josse
R G
RG
Xu
Z
Z
D000328:Adult; D019540:Area Under Curve; D001786:Blood Glucose / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D006943:Hyperglycemia / Q000517:prevention & control*; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D005894:Panax / Q000627:therapeutic use*; D008517:Phytotherapy; D010946:Plants, Medicinal; D019518:Postprandial Period; D013997:Time Factors; D016896:Treatment Outcome
D001786:Blood Glucose; D007004:Hypoglycemic Agents