Adaptogens for Blood Sugar and Metabolism: What Trials Found
What trials and reviews report for ginseng, holy basil, ashwagandha and astragalus on blood sugar and body weight, and why people on diabetes medicines should ask a pharmacist first.
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> If you take insulin or other diabetes medicines: NIH says some evidence suggests Asian ginseng might lower blood sugar and advises consulting your health care provider first, and says ashwagandha might interact with diabetes medicines. [1][2] Ask the prescriber or pharmacist before adding an adaptogen. Do not replace diabetes treatment with a supplement. [3]
The question
Products suggest adaptogens help "blood sugar balance," "metabolism" or weight loss. This page separates findings for different plants. A result for one plant, plant part or extract does not carry over to another.What the evidence shows
| Plant and use | What the source found | Strength of evidence | Population and form |
|---|---|---|---|
| Panax ginseng (genus) and fasting blood glucose | A meta-analysis of 16 trials found a modest drop in fasting glucose versus control; there was no significant effect on fasting insulin, insulin resistance or HbA1c overall. Most trials were short (67% under 12 weeks). [4] | Mixed | People with and without diabetes; varied ginseng products |
| Panax ginseng (Asian ginseng) in prediabetes and diabetes | NIH describes a 2022 review of 20 studies (1,295 participants) with improved fasting glucose, cholesterol and some inflammatory markers, but says overall research on blood sugar control in diabetes is inconclusive and conflicting. [1] | Mixed | Prediabetes and diabetes |
| Ocimum tenuiflorum (holy basil, tulsi; formerly O. sanctum) | A review of 24 human studies (searching books, theses and databases) reported favorable outcomes in metabolic disorders and no significant adverse events, and called for studies clarifying dosage and form. [5] | Promising but limited (varied designs and preparations) | Varied tulsi preparations |
| Withania somnifera (ashwagandha) and body weight | A trial of 52 adults under chronic stress (8 weeks) reported improvements in stress, food cravings and secondary measures that included body weight and BMI. [6] But a 2026 meta-analysis of 20 studies found no significant effect on body weight or body fat percentage. [7] | Mixed | Root extract; chronic stress vs. general adults |
| Astragalus (root) with metformin | NIH describes a 2024 review of 20 studies (953 adults with type 2 diabetes) where adding astragalus reduced fasting glucose and HbA1c more than metformin alone, but most studies were low quality. [8] | Insufficient evidence (low-quality studies) | Added to metformin |
| Ashwagandha and diabetes | NIH says there is not enough evidence to determine if it helps diabetes. [2] | Insufficient evidence |
The scientific name for holy basil is checked against GBIF, which lists Ocimum sanctum as a synonym of Ocimum tenuiflorum. [9]
Weight loss claims
The sources we read do not show that any adaptogen is a proven weight-loss aid. The two ashwagandha findings above disagree, and the meta-analysis found no effect on body weight. [7] Weight, diet and exercise guidance sits in prediabetes, type 2 diabetes and metabolic syndrome.Limits
- Blood glucose, HbA1c and cholesterol are markers; the trials did not show fewer complications.
- Most ginseng trials were short and often in people with good blood sugar control already (median HbA1c 7.1% in diabetes trials). [4]
- Asian ginseng trials are mostly small (under 200 participants) and under 3 months. [1]
Frequently asked questions
Does ginseng lower blood sugar?
A meta-analysis of 16 trials found a modest drop in fasting glucose but no clear effect on HbA1c overall; NIH calls the evidence in diabetes inconclusive. [4][1]
Does holy basil help with blood sugar?
A review of 24 human studies reported favorable metabolic outcomes, but it included varied designs and asked for more studies. [5]
Does ashwagandha help weight loss?
Evidence is mixed: one chronic-stress trial reported improved body weight measures, but a 2026 meta-analysis found no significant effect on body weight or body fat. [6][7]
Can adaptogens replace diabetes medicine?
No. NIH says it is very important not to replace medical treatment for diabetes with an unproven health product. [3]
Are adaptogens safe with diabetes medicines?
NIH says ashwagandha might interact with diabetes medicines and that Asian ginseng might lower blood sugar; ask a pharmacist or the prescriber. [2][1]
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
What regulators and health bodies say
Safety
References
- Asian Ginseng: Usefulness and Safety (NCCIH, NIH). Read 2026-10-23.
- Ashwagandha: Usefulness and Safety (NCCIH, NIH; last updated March 2023). Read 2026-10-23.
- Diabetes and Dietary Supplements: What You Need To Know (NCCIH, NIH). Read 2026-10-23.
- The effect of ginseng (the genus panax) on glycemic control: systematic review and meta-analysis, PLoS One 2014 (PubMed 25265315). Read 2026-10-23.
- The Clinical Efficacy and Safety of Tulsi in Humans: a systematic review, Evid Based Complement Alternat Med 2017 (PubMed 28400848). Read 2026-10-23.
- Body weight management in adults under chronic stress with ashwagandha root extract, J Evid Based Complementary Altern Med 2017 (PubMed 27055824). Read 2026-10-23.
- Effects of Withania somnifera on cognitive and physical function in adults: systematic review and meta-analysis, Front Pharmacol 2026 (PubMed 42199854). Read 2026-10-23.
- Astragalus: Usefulness and Safety (NCCIH, NIH). Read 2026-10-23.
- GBIF Backbone Taxonomy, species name matching (api.gbif.org species/match), checked for Withania somnifera, Rhodiola rosea, Panax ginseng, Panax quinquefolius, Ocimum sanctum, Astragalus mongholicus, Lepidium meyenii. Read 2026-10-23.