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Head-to-head evidence comparison — which supplement is right for you?
Iron wins 2 of 3 categories. Both are solid choices — the best pick depends on your specific goals.
Verdict
Likely helps
9 of 12 studies with measurable effects showed benefit.
Top outcomes
Verdict
Likely helps
11 of 15 studies with measurable effects showed benefit.
Top outcomes
Shared outcomes (1)
Outcomes where both Chromium and Iron have evidence — compare verdict strength side-by-side.
200-1000mcg daily
With meals (especially carb-containing), Can split doses with meals
Chromium Picolinate
18-45mg elemental iron for deficiency (varies by severity)
On empty stomach if tolerated, Away from tea, coffee, dairy
Ferrous bisglycinate (gentle, well-absorbed) or iron protein succinylate
May slightly reduce absorption of each other
Separate by 1 hour if taking therapeutic doses of chromium
8-16 weeks
2-4 weeks
8-12 weeks
2-4 weeks
4-8 weeks
4-12 weeks
The effectiveness of nutritional supplements in improving polycystic ovary syndrome in women: a systematic review and network meta-analysis
Reproductive biology and endocrinology : RB&E (2025) · Meta analysis · n=5501
Inositol significantly decreased total cholesterol and triglyceride levels, while curcumin was most effective in improving low-density and high-density lipoprotein cholesterol levels.
Comparative effects of vitamin and mineral supplements in the management of type 2 diabetes in primary care: A systematic review and network meta-analysis of randomized controlled trials
Pharmacological research (2023) · Meta analysis · n=14223
Low to very low certainty evidence established chromium supplements as the most effective in reducing fasting blood glucose levels and homeostasis model assessment of insulin resistance (SUCRAs: 90.4% and 78.3%, respectively).
Comparison of nutritional supplements in improving glycolipid metabolism and endocrine function in polycystic ovary syndrome: a systematic review and network meta-analysis
PeerJ (2023) · Meta analysis · n=2362
The network meta-analysis showed that carnitine, inositol, and probiotics reduced body weight and body mass index (BMI) compared to placebo, and carnitine outperformed the other supplements (SUCRAs: 96.04%, 97.73%, respectively).
Daily oral iron supplementation during pregnancy
The Cochrane database of systematic reviews (2024) · Meta analysis · n=48971
There is probably little to no difference in maternal death (2 versus 4 events, RR 0.57, 95% CI 0.12 to 2.69; 3 trials, 14,060 women; moderate-certainty evidence).
The Prevalence of Anemia among Pregnant Women in China: A Systematic Review and Meta-Analysis
Nutrients (2024) · Meta analysis · n=722
The results showed that the prevalence of anemia, ID, and IDA among pregnant women in China were 30.7% (95% CI: 26.6%, 34.7%), 45.6% (95% CI: 37.0%, 54.2%), and 17.3% (95% CI: 13.9%, 20.7%), respectively.
Treatment for women with postpartum iron deficiency anaemia
The Cochrane database of systematic reviews (2024) · Meta analysis · n=572
Intravenous iron versus oral iron supplementation The evidence is very uncertain about the effect of intravenous iron on mortality (risk ratio (RR) 2.95, 95% confidence interval (CI) 0.12 to 71.96; P = 0.51; I² = not applicable; 3 RCTs; 1 event; 572 women; very low-certainty evidence).
Meta-analysis showed ~19 mg/dL reduction in fasting glucose with chromium supplementation. Effects primarily demonstrated in type 2 diabetes patients. Chromium picolinate shows higher bioavailability than other forms.
Based on meta-analyses showing hemoglobin improvements of 2.01-5.30 g/dL in iron deficient populations. Higher doses show diminishing returns with increased GI side effects. Effectiveness varies significantly by baseline iron status and form used.
AI-estimated from published studies. Interpret as directional guidance.
Iron has a higher evidence score (9/10 vs 4.5/10) and wins in 2 of 3 categories.
May slightly reduce absorption of each other Separate by 1 hour if taking therapeutic doses of chromium Consult a healthcare provider for personalized advice.