Can you take Caffeine and Iron together?
Coffee can reduce non-heme iron absorption by 40–60%, primarily due to polyphenols rather than caffeine itself. Separate them by at least an hour.
Severity
Caution
Evidence
strong
Timing
Iron first, coffee 1+ hour later.
How it works
Chlorogenic acid and other polyphenols in coffee chelate non-heme iron, forming insoluble complexes in the gut.
Tea is even more inhibitory than coffee for iron absorption. Pure caffeine supplements have a smaller effect, but separation is still recommended. The polyphenol content, not the caffeine, drives most of the inhibition.
What to do
Take iron first thing in the morning on an empty stomach, then wait at least an hour before coffee. Pairing iron with Vitamin C helps counteract any residual inhibition.
Frequently asked
Should I separate Caffeine and Iron?
Consider separating them. Iron first, coffee 1+ hour later. Consult a healthcare professional for personalised advice.
Why do Caffeine and Iron interact?
Chlorogenic acid and other polyphenols in coffee chelate non-heme iron, forming insoluble complexes in the gut.
How strong is the evidence for this interaction?
The evidence is strong, supported by multiple published studies and clinical data.
About these supplements
Other Caffeine interactions
Other Iron interactions
Related reading
Check your full stack
for interactions.
See what competes, what combines well, and when to take everything. Every interaction cites a published source.
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6 supplements
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1 flagZinc and Iron compete for the same absorption pathway. Take at least 2 hours apart.
Supplements
This information is for educational purposes only. It is not medical advice and does not diagnose, treat, cure, or prevent any disease. Always consult a qualified healthcare professional.