Abstract
Background: Ginger contains gingerols, shagaols, paradols, gingerdiones, and terpenes, which have been shown to display anti-inflammatory properties and inhibit pain receptors. For this reason, ginger has been marketed as a natural analgesic. This study examined whether a specialized ginger extract obtained through supercritical CO(2) extraction and subsequent fermentation affects pain perception, functional capacity, and markers of inflammation. Methods: Thirty men and women (56.0 ± 9.0 years, 164.4 ± 14 cm, 86.5 ± 20.9 kg, 31.0 ± 7.5 kg/m(2)) with a history of mild to severe joint and muscle pain as well as inflammation participated in a placebo-controlled, randomized, parallel-arm study. Participants donated fasting blood, completed questionnaires, rated pain in the thighs to standardized pressure, and then completed squats/deep knee bends, while holding 30% of body mass, for 3 sets of 10 repetitions on days 0, 30, and 56 of supplementation. Participants repeated tests after 2 days of recovery following each testing session. Participants were matched by demographics and randomized to ingest 125 mg/d of a placebo or ginger (standardized to contain 10% total gingerols and no more than 3% total shogaols) for 58 days. Data were analyzed by a general linear model (GLM) analysis of variance with repeated measures, mean changes from the baseline with 95% confidence intervals, and chi-squared analysis. Results: There was evidence that ginger supplementation attenuated perceptions of muscle pain in the vastus medialis; improved ratings of pain, stiffness, and functional capacity; and affected several inflammatory markers (e.g., IL-6, INF-ϒ, TNF-α, and C-Reactive Protein concentrations), particularly following two days of recovery from resistance exercise. There was also evidence that ginger supplementation increased eosinophils and was associated with less frequent but not significantly different use of over-the-counter analgesics. Conclusions: Ginger supplementation (125 mg/d, providing 12.5 mg/d of gingerols) appears to have some favorable effects on perceptions of pain, functional capacity, and inflammatory markers in men and women experiencing mild to moderate muscle and joint pain. Registered clinical trial #ISRCTN74292348.