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Head-to-head evidence comparison — which supplement is right for you?
Berberine vs Iodine: they're closely matched on evidence (7.5 vs 8.5/10); they're alternatives for estrogen & progesterone balance — the best pick depends on your goals. Take the 60-second quiz for a pick tailored to your goals.
Berberine and Iodine are closely matched across evidence, studies, and safety.
Verdict
Likely helps
15 of 19 studies with measurable effects showed benefit.
Top outcomes
Verdict
Mixed evidence
4 of 11 studies with measurable effects showed benefit.
Top outcomes
500mg 2-3x daily (1000-1500mg total)
With meals, Split into 2-3 doses
Berberine HCl capsules
150-300mcg for maintenance; higher only if deficient under supervision
Any time with food
Potassium iodide (most common and studied)
4-12 weeks
8-12 weeks
First 2 weeks
If on diabetes medications
4-12 weeks
4-8 weeks
Clinical Efficacy of Curcumin, Resveratrol, Silymarin, and Berberine on Cardio-Metabolic Risk Factors Among Patients With Type 2 Diabetes Mellitus: A Systemic Review and Bayesian Network Meta-Analysis
Phytotherapy research : PTR (2025) · Meta analysis · n=1337
For HbA1c, silymarin was more effective than resveratrol (MD -2.08, 95%Cl -3.50 to -0.72) (P < 0.05).
Effects of berberine and barberry on selected inflammatory biomarkers in adults: A systematic review and dose-response meta-analysis of randomized clinical trials
Phytotherapy research : PTR (2023) · Meta analysis · n=1600
In addition, the non-linear analysis showed a significant lowering effect of berberine/barberry on IL-6 and TNF-α levels in doses <1000 mg/day and less than 5 weeks of intervention.
Berberine Ursodeoxycholate for the Treatment of Type 2 Diabetes: A Randomized Clinical Trial
JAMA network open (2025) · Rct · n=113
The study included 113 patients with T2D (mean [SD] age, 54.3 [10.6] years; 72 male [63.7%]) who were randomized.
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 meta-analyses showing FPG reduction of 0.59-0.82 mmol/L and HbA1c reduction of 0.63%. Studies primarily used berberine HCl with low bioavailability. Effects require divided doses and may take 8-12 weeks.
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.
Both Berberine and Iodine are closely matched — the best choice depends on your specific health goals.
Both Berberine and Iodine score equally (70) for estrogen & progesterone balance.
No known interactions between Berberine and Iodine have been documented in our database. However, always consult a healthcare provider before combining supplements.
The honest tier list — proven staples vs situational vs mostly marketing. The hub the other guides feed into.
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What genuinely lowers LDL/triglycerides — and why "red yeast rice" is a statin in disguise.
Berberine, inositol, magnesium vs the cinnamon/chromium hype — and the med-interaction warning.
The right pick depends on your goals. Answer a few quick questions for a personalised recommendation — or dig into the full evidence on each.