Table 1.
Studies and clinical trials on the effects of herbs and spices on metabolic syndrome risk factors.
| Herbs | Target/Groups | Dose/Duration | Main Outcome | Study Reference |
|---|---|---|---|---|
| Slimax: extract of several plants: Hordeum vulgare, Polygonatum multiflorum, Dimocarpus longan, Ligusticum sinense, Lilium brownie, and Zingiber officinale | Healthy participants | 6 weeks | Significant decrease in body weight and body mass index (BMI). | [55] |
| Significant reduction in waist and hip circumference. | ||||
| Herbal supplement: (Ma Huang & Guarana) | Overweight participants | 72 mg of ephedra and 240 mg of caffeine for 8 weeks. | Significant decrease in body weight and total body fat. | [56] |
| -Control group (n = 24) | Significant reduction in hip and waist circumference. | |||
| -Intervention group (n = 24) | ||||
| A compound of Aralia mandshurica (A) and Engelhardtia chrysolepis (E) extracts called ARALOX | Obese non-diabetic women, n = 32 | 450 mg of Aralia mandshurica (A) and 450 mg of Engelhardtia chrysolepis (E) per day for 15 weeks. | Decrease in total body weight and fat weight. | [59] |
| -Control group: Diet + placebo, n = 16 | Reduction in plasma TGs. | |||
| -Intervention group: | ||||
| Diet + compound, n = 16 | ||||
| White bean extract (Phaseolus vulgaris) | Obese adults | 3000 mg per day of each for 8 weeks. | Weight reduction in the intervention group. | [60] |
| -Control group: placebo, n = 25 | Decrease in plasma TGs. | |||
| -Intervention group: white bean extract, n = 25 | ||||
| Turmeric (Curcuma longa L.) | Prediabetic adults | 750 mg per day of each for 9 months. | 16.4% of subjects in the placebo group were diagnosed with type 2 diabetes mellitus. | [61] |
| -Control group: placebo, n = 25 | None of the participants from the Curcuma longa-treated group were diagnosed with type 2 diabetes mellitus. | |||
| -Intervention group: Curcuma longa, n = 25 | ||||
| Korean red ginseng (KRG) (Panax ginseng) | Overweight participants | 6 g per day of each for 12 weeks. | No change in HbA1c in both groups. | [62] |
| n = 19, with well-controlled type 2 diabetes | Intervention group maintained good glycemic control and improved plasma glucose and plasma insulin regulation. | |||
| -Control group: placebo, n = 9 | ||||
| -Intervention group: KRG, n = 10 | ||||
| Bitter lemon (Momordica charantia) | Newly diagnosed with diabetes adults, | 3 g per day of each for 12 weeks. | There was no significant effect on mean FBG, total cholesterol, and weight in both groups. | [63] |
| -Control group: placebo, n = 20 | ||||
| -Intervention group: Momordica charantia, n = 20 | ||||
| Cinnamon (Cinnamomum) | Participants diagnosed diabetes mellitus type 2 | 3 g per day of each for 16 weeks. | The cinnamon extract has a moderate effect in reducing fasting plasma glucose concentrations in diabetic patients. | [64] |
| -Control group: placebo, n = 39 | ||||
| -Intervention group: cinnamon powder, n = 40 | ||||
| A combination of Cissus quadrangularis (CQ) and Irvingia gabonensis (IG) | Overweight and obese participants | Intervention group: 300 mg CQ + 500 mg IG = 800 mg of compound per day. | Significant reduction in Cholesterol and LDL of FBG levels. | [65] |
| -Control group: placebo, n = 36 | Control group: 800 of placebo per day. | Significant decrease in body weight, body fat percent, and waist size in both groups. | ||
| -Intervention group: compound of CQ and IG, n = 36 | Duration: 10 weeks | |||
| Terminalia arjuna tree-bark powder | coronary heart disease (CHD) patients | Group I: placebo capsules; | Significant antioxidant action in the vitamin E group and T. arjuna tree group. | [66] |
| Group I: control group, n = 35 | Group II: vitamin E capsules 400 units per day; | Significant hypo-cholesterolemic effect in the T. arjuna tree group. | ||
| Group II: vitamin E group, n = 35 | Group III received finely pulverized T. arjuna tree bark-powder (500 mg) per day | |||
| Group III: T. arjuna tree bark-powder group, n = 35 | for 30 days. | |||
| Ginger (Zingiber officinale) | Diabetic adults | 3 g of each per day | Reduction in FBS and HbA1c. | [67] |
| -Control group: placebo, n = 44 | for 8 weeks. | Improvement in insulin resistance. | ||
| -Intervention group: ginger powder, n = 44 | ||||
| Black seed (Nigella stevia) and turmeric (Curcuma longa L.) | Males with MetS n = 250 (randomly distributed | Black seeds (1.5 g/day) | Black seeds reduced lipids and FBG, while turmeric reduced LDL-cholesterol and C-reactive protein (CRP). | [68] |
| -Control group: | Turmeric (2.4 g/day) | |||
| Placebo group, n = 64 | combination (900 mg Black seeds and 1.5 g Turmeric/day) | |||
| -Treatment group: | placebo (2 g) | |||
| -Turmeric group, n = 62 | for 8 weeks. | |||
| -Black seed group, n = 62 | ||||
| -Combination group, n = 62 | ||||
| Cinnamon, cardamom, saffron (Crocus sativus) and ginger (Zingiber officinale) | Type 2 diabetes participants | For 8 weeks, | Significant beneficial effects on cholesterol, but not on measures of glycemic control, oxidative stress, and inflammation. | [69] |
| -Control group: | three glasses of black tea and either 3 g/day of cardamom, or cinnamon, or ginger, or 1 g saffron. Control group received three tea glasses without any treatment. | |||
| Placebo, n = 39 | ||||
| -Treatment groups: | ||||
| Cinnamon, n = 40 | ||||
| Cardamom, n = 42 | ||||
| Saffron, n = 42 | ||||
| Ginger, n = 41 |