Iodine (Potassium Iodide) vs Magnesium L-Threonate
Mineral vs Sleep · evidence-backed comparison
- • Iodine (Potassium Iodide) has the stronger evidence base (strong (multiple rcts / meta-analyses)).
- • Magnesium L-Threonate has the broader effect profile across the 9 effect categories.
- • Iodine (Potassium Iodide) is cheaper per serving ($0.05 vs $1.10).
- • Magnesium L-Threonate has a slightly cleaner safety profile.
Side-by-side traits
| Trait | Iodine (Potassium Iodide) | Magnesium L-Threonate |
|---|---|---|
Category | Mineral | Sleep |
Active compound | Potassium iodide | Magnesium L-threonate |
Form available | Capsule, Tablet, Liquid | Capsule, Powder |
Source | mineral | synthetic |
Typical dose | 150 mcg daily | 1.5–2 g (≈144 mg elemental Mg) |
Dose range | 150–300 mcg | 1500–2000 mg |
Loading protocol | — | — |
Best taken with | with food | evening |
Best time of day | morning | evening |
Bioavailability How efficiently the body absorbs and utilizes the compound. | Very High (5/5) | Very High (5/5) |
Onset time | Cumulative: 2–8 weeks | Cumulative: 4–12 weeks |
Half-life | — | — |
Evidence level Quality and quantity of human research. | Strong (multiple RCTs / meta-analyses) | Limited (small studies) |
Overall effect Subjective effect magnitude. | Low (2/5) | Moderate (3/5) |
Muscle / strength | Very Low (1/5) | Very Low (1/5) |
Physical energy | Low (2/5) | Very Low (1/5) |
Focus / cognition | Very Low (1/5) | High (4/5) |
Mood / stress | Low (2/5) | Moderate (3/5) |
Sleep quality | Very Low (1/5) | High (4/5) |
Immunity | Low (2/5) | Very Low (1/5) |
Recovery Post-exercise recovery support. | Very Low (1/5) | Very Low (1/5) |
Longevity / healthspan | Low (2/5) | Moderate (3/5) |
Safety rating 5 = exceptionally well-tolerated; 1 = significant risk profile. | Moderate (3/5) | Very High (5/5) |
Price per serving Approximate USD per typical daily dose. | $0.05 | $1.10 |
Vegan friendly | Yes | Yes |
Gluten free | Yes | Yes |
3rd-party tested | Yes | Yes |
About Iodine (Potassium Iodide)
Essential for thyroid hormone synthesis. Iodized salt usually covers needs; supplement only if confirmed deficient.
About Magnesium L-Threonate
Only magnesium form proven to cross the blood-brain barrier in animals. Marketed for cognitive aging and sleep, but premium-priced.
Vetted brands, third-party testing, ships worldwide.
Vetted brands, third-party testing, ships worldwide.
Iodine (Potassium Iodide) safety
Common side effects:
- • Acne
- • Hyperthyroidism (high doses)
- • Goitre (paradox)
Avoid if:
- • Hyperthyroid
- • Graves' disease
- • Hashimoto's (caution)
Drug interactions:
- • Lithium
- • Anti-thyroid drugs
Magnesium L-Threonate safety
Common side effects:
- • Drowsiness
- • Headache (rare)
Avoid if:
- • Severe kidney disease
Drug interactions:
- • Bisphosphonates
Common uses
- • Thyroid support
- • Pregnancy
- • Iodine deficiency
Stacks well with: Selenium (Selenomethionine)
Common uses
- • Cognitive aging
- • Deep sleep
- • Memory
Stacks well with: Zinc, Vitamin D3
Related comparisons
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.