Loading…
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 about cookies
Head-to-head evidence comparison — which supplement is right for you?
Beetroot vs Iron: Iron has the stronger overall evidence (9 vs 7.5/10); they're alternatives for improve endurance — the best pick depends on your goals. Take the 60-second quiz for a pick tailored to your goals.
Iron wins 2 of 3 categories. Both are solid choices — the best pick depends on your specific goals.
Verdict
Likely helps
7 of 9 studies with measurable effects showed benefit.
Top outcomes
Verdict
Likely helps
6 of 8 studies with measurable effects showed benefit.
Top outcomes
400-500mg nitrates (or 500ml beetroot juice) (the cited trials gave about 260 to 1,040 mg of nitrate, none gave 400 to 500 mg)
2-3 hours before exercise
Concentrated beetroot shots (70ml)
18-40mg elemental iron for deficiency (varies by severity) (a typical label dose, not the dose used in the cited trials, which used 60 to 120 mg a day)
On empty stomach if tolerated, Away from tea, coffee, dairy
Ferrous bisglycinate (gentle, well-absorbed) or iron protein succinylate
and 6 more not shown
2-3 hours after intake
2-3 hours
Immediate
30-60 minutes
2-4 weeks
4-8 weeks
4-12 weeks
Dietary Nitrate Supplementation and Exercise Performance: An Umbrella Review of 20 Published Systematic Reviews with Meta-analyses
Sports Medicine (2025) · Meta analysis · n=2672
Twenty systematic reviews with meta-analyses, representing 180 primary studies and 2672 unique participants, met the inclusion criteria.
Effects of Beetroot Juice on Physical Performance in Professional Athletes and Healthy Individuals: An Umbrella Review
Nutrients (2025) · Systematic review
Fifteen meta-analyses were included in this Umbrella Review.
Sport supplementation in competitive swimmers: a systematic review with meta-analysis
Journal of the International Society of Sports Nutrition (2025) · Meta analysis · n=422
This revision included 23 studies, 16 of them (69.6%) qualified as excellent and 7 (30.4%) as good at the methodological level based on the punctuation in the PEDro scale.
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=1376204
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=4558
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).
The points come from one crossover dose-response trial in 10 healthy men given 70, 140 or 280 mL of concentrated beetroot juice, containing 4.2, 8.4 and 16.8 mmol of nitrate (about 260, 521 and 1,042 mg), 2.5 hours before cycling (PMID 23640589). 70 mL did not change the exercise responses compared with nitrate-depleted placebo. 140 and 280 mL extended time to task failure in severe cycling by 14% and 12%, and the higher dose gave no further improvement, so the curve is flat above 521 mg. The abstract does not report tolerability, so no ceiling is set. The curve rests on acute single doses in young men and cannot show effects of daily use, in women, in older adults or in trained athletes.
AI-estimated from published studies. Interpret as directional guidance.
Iron has a higher evidence score (9/10 vs 7.5/10) and wins in 2 of 3 categories.
For improve endurance, Beetroot has a higher relevance score (95 vs 75).
No documented interaction was found in the data searched. This does not establish that this exact combination is safe.
Caffeine, citrulline, beta-alanine, creatine — the ingredients that work, at clinical doses (vs fairy dusting).
On Ozempic/Wegovy/Mounjaro? What actually helps — muscle preservation, GI relief, nutrient gaps (no upsell).
Tired? Why most "energy" pills only work if they fix a deficit — and how to find yours first.
Selenium helps; iodine can WORSEN Hashimoto’s. The honest take on "thyroid support".
The right pick depends on your goals. Answer a few quick questions for a personalised recommendation — or dig into the full evidence on each.