Supplement
Wild yam is a climbing vine whose root contains diosgenin, a plant compound with a structure similar to steroid hormones. The best-supported finding is for thinking skills: in a small crossover trial of 28 healthy adults, a diosgenin-rich extract improved cognition, though the evidence is limited. Other studies were also small, with blood pressure improving in one and hormone results in menopause coming out mixed.
Sources: PMID 29064406
- Updated
- How we grade
- 5 studies cited
- Best evidence
- Grade C
- Conditions studied
- 6
- Outcomes
- 29
- Graded outcomes
- 0070
Evidence by condition
- Strong
- Moderate
- Limited
- Very limited
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Cognition Small Improvement | Improves (the measure goes up) | Small effect | 1 study | 28 people | ||
| Cognitive Decline | Improves (the measure goes down) | 28 people | ||||
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| DHEAS Small Increase | Improves (the measure goes up) | Small effect | 50 people | |||
| Estrogen Mixed effect | 50 people | |||||
| Menopausal Symptoms | Improves (the measure goes down) | 1 study | 50 people | |||
Studies that measured menopausal symptoms | ||||||
| Follicle-Stimulating Hormone | Improves (the measure goes up) | 50 people | ||||
Premenstrual Syndrome (PMS)
- Estrogen
- Prostaglandin E2: improves
- Pain: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Estrogen Mixed effect | 10 people | |||||
| Prostaglandin E2 | Improves (the measure goes down) | 1 study | 10 people | |||
| Pain | Improves (the measure goes down) | 10 people | ||||
| Progesterone | Improves (the measure goes up) | 10 people | ||||
Menstrual Health
- Estrogen
- Prostaglandin E2: improves
- Pain: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Estrogen Mixed effect | 10 people | |||||
| Prostaglandin E2 | Improves (the measure goes down) | 1 study | 10 people | |||
| Pain | Improves (the measure goes down) | 10 people | ||||
| Progesterone | Improves (the measure goes up) | 10 people | ||||
Neurological Health
- Hematocrit
- Liver Enzymes: changes; see studies
- Pain: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Hematocrit Mixed effect | 25 people | |||||
| Liver Enzymes | Changes; see studies | 1 study | 25 people | |||
| Pain | Improves (the measure goes down) | 25 people | ||||
| Red Blood Cell Count | Improves (the measure goes up) | 25 people | ||||
| Urinary Albumin | Improves (the measure goes up) | 25 people | ||||
| White Blood Cell Count | Improves (the measure goes up) | 25 people | ||||
Healthy Muscle Aging
- Blood Pressure: improves
- Body Mass Index (BMI): improves
- HbA1c: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Blood Pressure Small Improvement | Improves (the measure goes down) | Small effect | 66 people | |||
| Body Mass Index (BMI) | Improves (the measure goes down) | 1 study | 66 people | |||
Studies that measured body mass index (bmi) | ||||||
| HbA1c | Improves (the measure goes down) | 66 people | ||||
| Heart Rate | Improves (the measure goes down) | 66 people | ||||
| High-density lipoprotein (HDL) | Improves (the measure goes up) | 66 people | ||||
| Muscle Mass | Improves (the measure goes up) | 66 people | ||||
| Muscular Endurance | Improves (the measure goes up) | 66 people | ||||
| Strength | Improves (the measure goes up) | 66 people | ||||
| Total cholesterol | Improves (the measure goes down) | 66 people | ||||
Key findings
- CognitionImproves (the measure goes up)
- DHEASImproves (the measure goes up)
- Estrogen
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- Grade C
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Studies cited
5 studies from PubMed
- Diosgenin-Rich Yam Extract Enhances Cognitive Function: A Placebo-Controlled, Randomized, Double-Blind, Crossover Study of Healthy Adults.
- Dioscorea esculenta Intake with Resistance Training Improves Muscle Quantity and Quality in Healthy Middle-Aged and Older Adults: A Randomized Controlled Trial.
- The assessment of efficacy of Diascorea alata for menopausal symptom treatment in Taiwanese women.
- Evaluation of the safety of Sanyak (Dioscoreae rhizoma) pharmacopuncture according to the extraction method: a double-blind randomized controlled trial.
- The effect of Dioscorea esculenta powder on prostaglandin E(2) and cytochrome c oxidase subunit 2 levels, menstrual pain, and premenstrual syndrome in young women: A randomized double-blind controlled trial.