Mild interactionMildSeparate by 4h
Dairy (milk, yoghurt) and Levothyroxine: interaction, severity and spacing
Dairy (milk, yoghurt) and Levothyroxine interact because the calcium in milk binds levothyroxine; even a splash in the coffee you take it with lowers absorption. Take them 4 hours apart. Mild risk.
Last reviewed: 2026-09-20Reviewed by: StackingRight clinical review
The interaction in detail
| Pair | Dairy (milk, yoghurt) and Levothyroxine |
|---|---|
| Type | Food interaction |
| Severity | Mild |
| Required spacing | 4 hours minimum |
| Onset | At the time of dosing |
Mechanism
The calcium in milk binds levothyroxine; even a splash in the coffee you take it with lowers absorption.
What to do
Take levothyroxine with plain water only, at least 30-60 minutes before breakfast.
How to fit both into one day
Levothyroxine
morningempty stomach
Levothyroxine needs an empty stomach and gastric acid for full absorption. Take it 30-60 minutes before breakfast with plain water, and keep calcium, iron and coffee at least 4 hours away.
Putting Dairy (milk, yoghurt) in the morning and Levothyroxine in the morning satisfies the 4-hour separation without disrupting either one's absorption window.