Ashwagandha vs Selenium (Selenomethionine)
Adaptogen vs Mineral · evidence-backed comparison
- • Ashwagandha has the broader effect profile across the 9 effect categories.
- • Selenium (Selenomethionine) is cheaper per serving ($0.10 vs $0.30).
- • Ashwagandha has a slightly cleaner safety profile.
- • Selenium (Selenomethionine) has higher bioavailability (better absorption).
Side-by-side traits
| Trait | Ashwagandha | Selenium (Selenomethionine) |
|---|---|---|
Category | Adaptogen | Mineral |
Active compound | Withanolides | Selenomethionine |
Form available | Capsule, Powder, Liquid | Capsule, Tablet |
Source | plant | synthetic |
Typical dose | 300–600 mg (5% withanolides) | 100–200 mcg daily |
Dose range | 300–600 mg | 100–200 mcg |
Loading protocol | — | — |
Best taken with | with food | with food |
Best time of day | any | any |
Bioavailability How efficiently the body absorbs and utilizes the compound. | High (4/5) | Very High (5/5) |
Onset time | Cumulative: 4–8 weeks | Cumulative: 4–12 weeks |
Half-life | ~7 hours | ~252 days (long body store) |
Evidence level Quality and quantity of human research. | Moderate (some RCTs) | Moderate (some RCTs) |
Overall effect Subjective effect magnitude. | Moderate (3/5) | Low (2/5) |
Muscle / strength | Moderate (3/5) | Very Low (1/5) |
Physical energy | Moderate (3/5) | Low (2/5) |
Focus / cognition | Moderate (3/5) | Very Low (1/5) |
Mood / stress | High (4/5) | Low (2/5) |
Sleep quality | High (4/5) | Very Low (1/5) |
Immunity | Moderate (3/5) | Moderate (3/5) |
Recovery Post-exercise recovery support. | High (4/5) | Low (2/5) |
Longevity / healthspan | Moderate (3/5) | Moderate (3/5) |
Safety rating 5 = exceptionally well-tolerated; 1 = significant risk profile. | High (4/5) | Moderate (3/5) |
Price per serving Approximate USD per typical daily dose. | $0.30 | $0.10 |
Vegan friendly | Yes | Yes |
Gluten free | Yes | Yes |
3rd-party tested | Yes | Yes |
About Ashwagandha
The most clinically-studied adaptogen. Reliably lowers cortisol, raises testosterone in stressed men, and improves sleep onset.
About Selenium (Selenomethionine)
Cofactor for glutathione peroxidase and thyroid hormone activation. Two Brazil nuts per day already meet requirements; toxicity above 400 mcg.
Vetted brands, third-party testing, ships worldwide.
Vetted brands, third-party testing, ships worldwide.
Ashwagandha safety
Common side effects:
- • Mild GI upset
- • Drowsiness
- • Increased thyroid hormone
Avoid if:
- • Hyperthyroid
- • Pregnancy
- • Autoimmune disease (theoretical)
Drug interactions:
- • Thyroid meds
- • Sedatives
- • Immunosuppressants
Selenium (Selenomethionine) safety
Common side effects:
- • Selenosis (>400 mcg/day): hair loss, garlic breath, brittle nails
Avoid if:
- • Already eating Brazil nuts daily
Drug interactions:
- • Anticoagulants
Common uses
- • Stress / anxiety
- • Sleep
- • Testosterone (in stressed men)
- • Strength
Stacks well with: Rhodiola Rosea, Magnesium Glycinate
Common uses
- • Thyroid support
- • Hashimoto's
- • Antioxidant
Stacks well with: Iodine (Potassium Iodide)
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Medical disclaimer
SupplementDuel is for educational purposes only and is not medical advice. Consult a physician before starting, stopping, or combining supplements — especially if you are pregnant, breastfeeding, take prescription medication, or have a chronic condition.