Table 1. Characteristics of Studies Investigating the Effect of Ginseng on Glycemic Outcomes.
| Study* | Subject characteristics† | Age (y) | BMI (kg/m2)‡ | Setting | Glucose (mmol/L)§ | Insulin (pmol/L)§ | HbA1c (%)§ | HOMA-IR§ | Design | Ginseng form | Ginseng preparation | Ginseng dose∥ | Ginseng species | Comparator¶ | Follow-up | MQS** | Funding Sources†† | Manufacturer |
| Diabetes | ||||||||||||||||||
| Chio et al. 1997 [19] | 31subjects with T1DM (15M:16F) | T: 51.6±10.9; C: 50.4±7.5 | N/R | OP, Korea | T: 10.9±3.1; C: 13.2±4.4 | N/R | T: 9.0±1.8; C: 10.1±2.6 | N/R | Parallel | Capsule | Korean red ginseng (Unspecified preparation method) | 2.7 g/d | Panax ginseng | No ginseng | 24 wks | 8 | N/R | N/R |
| Kim et al. 2011 [21] | 38 subjects with T2DM (23M:15F) | T: 56.0±7.2; C: 51.2±10.7 | T: 24.8±2.7; C: 23.9±3.0 | OP, Korea | T: 7.6±0.9; C: 8.1±1.5 | T: 65.9±21.5; C: 63.9±20.8 | T: 7.4±1.0; C: 7.5±1.2 | T: 3.1±1.1; C: 3.2±1.2 | Parallel | Capsule | Fermented Korean red ginseng (Unspecified preparation method) | 780.0 mg/d | Panax ginseng | Placebo | 12 wks | 6 | Agency | N/R |
| Ma et al. 2008 [22] | 20 subjects with T2DM (12M:8F) | 51.0± 8.5 | 28.5±5.8 | OP, Hong Kong | 8.3±3.1 | 149±111.9 | N/R | 7.4±3.8 | Crossover | Capsule | Roots of Panax ginseng | 2214.0 mg/d | Panax ginseng | Placebo | 4 wks | 8 | Agency | N/R |
| Reeds et al. 2011 [25] | 15 subjects with Pre-DM and T2DM (1M:14F) | 46.0±11.6 | T1: 35.0±6.7; T2: 36.0±4.5; C: 31.0±2.2 | OP, USA | 5.2±0.2 | 52.4±22.5 | 5.9±0.4 | N/R | Parallel | Capsule | T1: Extract of Korean red ginseng; T2: Ginsenoside Re | T1: 3.0 g/d first 2wks, 8.0 g/d following 2wks; T2: 3.0 g/d first 2wks, 8.0 g/d following 2wks | Panax ginseng | Placebo | 4 wks | 10 | Agency | Spectrum laboratories, Gardena AIPOP, Gangdown-Do, Korea |
| Sotaniemi et al. 1995 [7] | 36 subjects with T1DM (16M:20F) | T1: 59.7±7.0; T2: 57±9.0; C: 60±6.0 | N/R | OP, Finland | 8.3±1.3 | N/R | 6.5±1.7 | N/R | Parallel | Capsule | Extract of unspecified ginseng type | T1: 100.0 mg/d; T2: 200.0 mg/d | Unspecified | Placebo | 8 wks | 7 | N/R | Dansk droge, Copenhagen, Denmark |
| Vuksan et al.2000 [29] | 24 subjects with T2DM (13M:11F) | 64.0±7.0 | 28.0±5.0 | OP, Canada | 8.3±2.5 | 88.1±66.9 | 7.1±0.1 | 5.4±3.9 | Crossover | Capsule | Extract of American ginseng (CNT2000) | 3.0 g/d | Panax quinquefolius | Placebo | 8 wks | 7 | Industry | Chai-Na-Tai Corporation, Langley, BC, Canada |
| Vuksan et al. 2008 [9] | 19 subjects with T2DM (11M:8F) | 64.0±8.7 | 28.9±6.1 | OP, Canada | 7.7±1.7 | 35.0±17.4 | 6.5±0.3 | 1.7±0.9 | Crossover | Capsule | Rootlets of Korean red ginseng | 6.0 g/d | Panax ginseng | Placebo | 12 wks | 8 | Agency | Korea Ginseng Manufacturing Plant, Chung-buk, Korea |
| Yoon et al. 2012 [30] | 72 subjects with T2DM (44M:28F) | T1: 52.7±11.0; T2: 52.7±10.0; T3: 51.1±8.6; C: 54.8±10.0 | T1: 26.3±4.8; T2: 24.0±2.6; T3: 25.4±2.7; C: 25.3±1.92 | OP, Korea | T1: 9.2±2.2; T2: 9.6±1.9; T3: 8.9±1.5; C: 8.3±1.8 | T1: 80.6±39.6; T2: 65.9±30.6; T3: 84.0±45.8; C: 68.8±29.2 | T1: 7.8±1.3; T2: 7.8±1.2; T3: 7.7±0.8; C: 7.6±0.4 | T1: 4.7±2.5; T2: 4.1±2.0; T3: 4.9±2.9; C: 3.8±2.1 | Parallel | Capsule | Vinegar extract of Panax ginseng (Ginsam) | T1: 500.0 mg/d; T2: 2000.0 mg/d; T3: 3000.0 mg/d | Panax ginseng | Placebo | 8 wks | 10 | Industry | YuYu Pharamaceutical Seoul, Korea |
| Zhang et al. 2007 [32] | 84 subjects with Pre-DM and T2DM (51M:33F) | T: 62.9±12.0; C: 63.4±10.5 | N/R | IP, China | 7.7±1.91 | 58.8±57.4 | N/R | 1.1±0.57 | Parallel | Capsule | Extract of Panax quinquefolius saponin (PQS) | 1.8 g/d | Panax quinquefolius | No Ginseng | 4 wks | 8 | Agency | Manufacturer name reported in Chinese |
| Non-diabetes | ||||||||||||||||||
| Dickman et al. 2009 [20] | 25 Otherwise healthy females | T: 62.3±5.9; C: 61.7±6.5 | T: 25.3±3.8; C: 24.7±2.5 | OP, USA | 4.6±0.5 | N/R | N/R | N/R | Parallel | Capsule | Dry whole root of American ginseng | 1.0 g/d | Panax quinquefolius | Placebo | 16 wks | 7 | Agency | Kaiser Farms,Wausau,Wi |
| Park et al. 2012 [23] | 48 Females with Pre-DM | T: 43.1±10.6; C: 46.2±11.0 | N/R | OP, Korea | T: 5.9±1.0; C: 6.4±3.7 | T: 77.0±60.4; C: 68.8±71.5 | N/R | T: 3.1±2.9; C: 3.1±4.2 | Parallel | Capsule | Roots of Korean red ginseng | 4.5 g/d | Panax ginseng | Placebo | 12 wks | 8 | Agency | Korea Ginseng Corporation, Seoul, Korea |
| Reay et al. (a) 2009 [24] | 23 Otherwise healthy subjects (12M:11F) | 35.6±1.1 | N/R | OP, UK | 4.9±0.9 | 72.9±28.0 | 5.5±0.3 | N/R | Crossover | Capsule | Extract of Panax Ginseng (G115) | 200.0 mg/d | Panax ginseng | Placebo | ∼8 wks | 10 | Industry | Pharmaton SA, Lugano, Switzerland |
| Reay et al. (b) 2009 [24] | 14 Otherwise healthy subjects (5M:9F) | 38.4±10.6 | N/R | OP, UK | 5.7±0.5 | 97.2±36.8 | 5.5±0.36 | N/R | Crossover | Capsule | Extract of Panax ginseng (Cheong Kwan Jang) | 200.0 mg/d | Panax ginseng | Placebo | ∼8 wks | 10 | Industry | Korea Ginseng Corporation, Seoul, Korea |
| Rhee et al. 2011 [26] | 64 subjects with EHPT (28M:36F) | T: 55.0±9.0; C: 58.0±6.0 | T: 24.9; C: 24.7 | OP, Korea | T: 5.7±0.6; C: 5.6±0.6 | N/R | N/R | N/R | Parallel | Capsule | Extract of Korean red ginseng | 3.0 g/d | Panax ginseng | Placebo | 12 wks | 7 | Agency & Industry | Korea Ginseg Co, Daejeon, Korea |
| Scaglione et al. 1996 [27] | 227 Otherwise healthy subjects (132M:95F) | T: 48.0±16.4; C: 48.5±16.5 | T: 23.5±1.2; C: 23.4±1.2 | OP, Italy | 5.3±0.7 | N/R | N/R | N/R | Parallel | Capsule | Extract of Panax ginseng (G115) | 200.0 mg/d | Panax ginseng | Placebo | 12 wks | 8 | N/R | Pharmaton SA, Lugano, Switzerland |
| Shin et al. 2011 [28] | 30 subjects with Pre-DM (18M:12F) | T: 47.1±10.8; C: 45.9±10.5 | T: 24.9±7.4; C: 22.6±9.3 | OP, Korea | T: 6.7±0.9; C: 6.2±0.9 | N/R | N/R | N/R | Parallel | Capsule | Extract of Korean red ginseng with cheonggukjang (fermented soybean) | 20.0 g/d | Panax ginseng | Cheonggukjang (fermented soybean) | 8 wks | 10 | Agency | Keimyung Foodex Co, Daegu, Korea |
Abbreviations: T1DM – Type 1 Diabetes mellitus; T2DM – Type 2 Diabetes mellitus; Pre-DM – Pre-diabetes Mellitus; EHPT – Essential hypertension; F – Female; M – Male; BMI – Body mass index; C – Control group; T – Treatment group; T1 – Treatment group #1; T2 – Treatment group #2; T3 – Treatment group #3; IP – Inpatient; OP – Outpatient; MQS – Heyland Methodological Quality Score; N/R – Not reported.
*Studies by Sotaniemi et al. [7], Yoon et al. [30], and Reeds et al. [25] contained multiple comparisons, and to mitigate unit-of-analysis error, we combined groups to create a single pairwise comparison.
Pre-DM included subjects with either Impaired Fasting Glucose or Impared Glucose Tolerance.
Pre-study baseline BMI is listed. The study by Rhee et al. [26] did not report SD for the mean BMI of participants.
Pre-study baseline endpoints are listed. In studies were these values were not reported, the start value of control was assumed to be equivalent to baseline and was reported. Where start of control value was not given, of control value was assumed to be equivalent to baseline and was reported. Assumed values are reported in bold. The study by Reay et al. (a) & (b) [24] used n = 23 and n = 14 respectively for reporting data on fasting blood glucose, n = 17 and n = 12 respectively for reporting data on fasting plasma insulin, and n = 18 and n = 11 respectively for reporting data on HbA1c.
∥Ginseng dose is reported individually for trials with multiple treatment groups.
All ginseng doses were compared to placebo, a control group that did not receive ginseng, or fermented soybean.
**Study quality was assessed by the Heyland Methodological Quality Score (MQS) and trials with a score ≥ 8 were considered to be of high quality.
Agency funding is that from government, university or not-for-profit health agency sources. None of the trialists declared conflicts of interest.
All data is expressed as mean ± SD.