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Head-to-head evidence comparison — which supplement is right for you?
Maca wins 2 of 3 categories. Both are solid choices — the best pick depends on your specific goals.
Verdict
Mixed evidence
4 of 12 studies with measurable effects showed benefit.
Top outcomes
Verdict
Likely helps
3 of 3 studies with measurable effects showed benefit.
Top outcomes
Shared outcomes (1)
Outcomes where both Iodine and Maca have evidence — compare verdict strength side-by-side.
150-300mcg for maintenance; higher only if deficient under supervision
Any time with food
Potassium iodide (most common and studied)
1500-3000mg
Morning or early afternoon, With food
Gelatinized maca powder (easier to digest)
4-12 weeks
4-8 weeks
6-12 weeks
4-8 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.
Effects of Maca (Lepidium meyenii Walp.) on Physical Performance in Animals and Humans: A Systematic Review and Meta-Analysis
Nutrients (2024) · Meta analysis
They revealed a large effect for all outcomes (SMD: FST = 2.26, RRT = 6.26, GST = 5.23, LA = -1.01, and BLA = -1.70).
A review of the study of active components and their pharmacology value in Lepidium meyenii (Maca)
Phytotherapy research : PTR (2021) · Systematic review
Additionally, the research on the change of active components in Maca at different growth stages by MS will be beneficial to full utilization of active components in Maca and other natural resources.
Enhancement of Interferon-γ Secretion by Lepidium meyenii Extract Supplementation After Exhaustive Endurance Exercise in Healthy Men: A Double-blind, Placebo-controlled Trial
International journal of medical sciences (2025) · Rct · n=20
Regarding the main time effect, the number of lymphocytes in all participants was significantly lower at 2 and 4 hours after exercise than before supplementation.
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 meta-analysis showing large effect sizes for physical performance outcomes. Effects may vary significantly between raw and gelatinized forms. Limited human studies with small sample sizes.
AI-estimated from published studies. Interpret as directional guidance.
Maca has a higher evidence score (5.5/10 vs 8.5/10) and wins in 2 of 3 categories.
For boost daily energy, Iodine has a higher relevance score (95 vs 70).
No known interactions between Iodine and Maca have been documented in our database. However, always consult a healthcare provider before combining supplements.