Caffeine + Iron

Can you take Caffeine and Iron together?

ConflictHuman data

Separate them — take iron at least an hour before your coffee or tea.

What to do. Take iron on waking with water, and have coffee or tea at least 1 hour later.

Mechanism

Coffee and tea reduce iron absorption

A cup of coffee with a meal cut non-heme iron absorption by roughly 40% or more in single-meal studies, mainly because of polyphenols (chlorogenic acid) rather than caffeine itself. Tea has a similar effect.

Evidence: Human data — Human pharmacokinetic, cohort or case-series data.

Timing

A day with Caffeine and Iron

  1. 07:00

    On waking

    no food
  2. 08:00

    Breakfast

    with meal

Taking more than these two?

Add the rest of your stack and your medications for a complete check.

Check my full stack

Buying guide

What to look for on the label

  • Caffeine

    • Coffee or tea counts
    • If using pills, pair with L-theanine
  • Iron

    • Iron bisglycinate (gentler on the stomach)
    • Check the label for elemental iron, not the salt weight

Related

Other interactions

Learn more about Caffeine and Iron.