We use essential cookies (authentication, your saved goals/stack) by default. With your permission we'll also enable privacy-respecting analytics (Vercel Web Analytics, anonymous load-time metrics) and error-replay diagnostics (Sentry — DOM snapshots only when an error fires) so we can fix bugs faster. Learn more
Head-to-head evidence comparison — which supplement is right for you?
Iodine wins 2 of 3 categories. Both are solid choices — the best pick depends on your specific goals.
Verdict
Mixed evidence
4 of 11 studies with measurable effects showed benefit.
Top outcomes
Verdict
Mostly mechanism / observational
2 of 2 studies with measurable effects showed benefit.
Top outcomes
150-300mcg for maintenance; higher only if deficient under supervision
Any time with food
Potassium iodide (most common and studied)
300–500 mg daily
Morning with breakfast, Split dosing (morning and midday) for doses above 500 mg
Nicotinamide Riboside Chloride capsules or powder
4-12 weeks
4-8 weeks
1–2 weeks
4–8 weeks
8–16 weeks
4–8 weeks
Maternal Iodine Status and Birth Outcomes: A Systematic Literature Review and Meta-Analysis
Nutrients (2023) · Meta analysis · n=42269
Birth weight was similar between UIC ≥ 150 μg/L and <150 μg/L (difference = 30 g, 95% CI −22 to 83, p = 0.3, n = 13, I2 = 89%) with no evidence of linear trend (4 g per 50 μg/L, −3 to 10, p = 0.2, n = 12, I2 = 80%).
Iodine fortification of foods and condiments, other than salt, for preventing iodine deficiency disorders
The Cochrane database of systematic reviews (2019) · Meta analysis · n=4317
This is equivalent to an increase of 38.32 µg/L (95% CI 24.03 to 52.61 µg/L).
Systematic review and meta-analysis of iodine nutrition in modern vegan and vegetarian diets
The British journal of nutrition (2023) · Meta analysis · n=4421
Vegan diets had the poorest iodine intake (17·3 µg/d) and were strongly associated with lower iodine intake (P = < 0·001) compared with omnivorous diets.
The Effect of Nicotinamide Mononucleotide and Riboside on Skeletal Muscle Mass and Function: A Systematic Review and Meta-Analysis.
Journal of cachexia, sarcopenia and muscle (2025) · Meta analysis
Systematic review and meta-analysis evaluating NMN and NR effects on skeletal muscle mass and function
NAD+ supplementation for anti-aging and wellness: A PRISMA-guided systematic review of preclinical and clinical evidence.
Ageing research reviews (2026) · Systematic review
PRISMA-guided systematic review of both preclinical and clinical NAD+ supplementation literature
NAD+ therapy in age-related degenerative disorders: A benefit/risk analysis.
Experimental gerontology (2020) · Systematic review
Systematic review of 147 articles (113 preclinical, 34 clinical) on NAD+ precursor therapy
Based on meta-analyses showing urinary iodine concentration increases with supplementation. Effects only meaningful in iodine-deficient populations. Excessive intake (>300mcg) may increase thyroid cancer risk. Most studies used potassium iodide; kelp-derived forms have variable bioavailability.
Based on 8-week RCT showing dose-dependent increases of 22%, 51%, and 142% at 100, 300, and 1000mg respectively. Individual response varies significantly (30% show variable response). NR-SAFE trial confirmed safety up to 2000mg.
AI-estimated from published studies. Interpret as directional guidance.
Iodine has a higher evidence score (9/10 vs 7.2/10) and wins in 2 of 3 categories.
For boost daily energy, Iodine has a higher relevance score (95 vs 78).
No known interactions between Iodine and Nicotinamide Riboside have been documented in our database. However, always consult a healthcare provider before combining supplements.