So if you are taking any form of levothyroxine
(Synthroid, Unithroid, etc.), do not take any calcium- or iron
-containing foods or supplements within four hours of taking the levothyroxine. This means avoiding milk and yoghurt – two classic breakfast foods. It also means avoiding eggs and baked beans, which are surprisingly high in iron. (But eggs are also rich in iodine, so they are a brilliant food to pick for lunch, once you've safely converted any thyroxine tablets from T4 to T3).