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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
Probably helps
4 of 7 studies with measurable effects showed benefit.
Top outcomes
Verdict
Mixed evidence
4 of 11 studies with measurable effects showed benefit.
Top outcomes
400mg extract (standardized to 10-30% andrographolides), 3x daily for acute use
At first sign of cold symptoms, With meals
Standardized extract (10-30% andrographolides)
150-300mcg for maintenance; higher only if deficient under supervision
Any time with food
Potassium iodide (most common and studied)
2-5 days
2-5 days
2-5 days
4-12 weeks
4-8 weeks
Herbal Medicines for the Treatment of Active Ulcerative Colitis: A Systematic Review and Meta-Analysis
Nutrients (2024) · Meta analysis
In pooled analyses, when compared with placebo, clinical response rates were significantly higher for Indigo naturalis (IN) (RR 3.70, 95% CI 1.97-6.95), but not for Curcuma longa (CL) (RR 1.60, 95% CI 0.99-2.58) or Andrographis paniculata (AP) (RR 0.95, 95% CI 0.71-1.26).
Safety of Andrographis paniculata: A systematic review and meta-analysis
Pharmacoepidemiology and drug safety (2021) · Meta analysis · n=1000
Incidence of serious AEs was very rare with the pooled incidence (95% CI) from RCTs of 0.02 per 1000 patients (0.0-0.5).
A double-blind, randomized, placebo-controlled study to assess the efficacy of Andrographis paniculata standardized extract (ParActin®) on pain reduction in subjects with knee osteoarthritis
Phytotherapy research : PTR (2019) · Rct · n=103
Patients treated with 300 or 600 mg/day of ParActin® showed a significant reduction in pain at days 28, 56, and 84 compared with a placebo group.
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.
Based on RCT showing significant improvement in cough (SMD -0.39) and sore throat symptoms. Conservative effectiveness estimates due to moderate effect sizes in meta-analysis of respiratory infections.
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.
AI-estimated from published studies. Interpret as directional guidance.
Iodine has a higher evidence score (9/10 vs 8.5/10) and wins in 2 of 3 categories.
No known interactions between Andrographis and Iodine have been documented in our database. However, always consult a healthcare provider before combining supplements.