Expert: Leo Nollet - 10/29/2009

Question
Hello!  I keep running into articles which tell me that you shouldn't drink milk with tea, because the milk does something to the polyphenols.  I'm trying to get more details on this issue, but I'm coming up blank.

Does this mean that I can't have any dairy around the same time as I drink tea?  If so, how long should I leave between them?  For instance, if I drink some tea, can I eat a piece of cheese an hour later or will that ruin the health benefits of the tea I drank?  Also, the articles only mention tea, but doesn't this apply to polyphenols from other sources?  Wouldn't it also mean that I shouldn't put milk in my coffee, for example?

Thank you for taking the time to read my question!

Answer
Dear Miranda,
A team of scientists found that casein proteins from milk blocked the effect of tea all by themselves. These proteins bind specifically to tea chemicals which cause rat aorta to relax, and especially a catechin called EGCG. Catechins are a kind of polyphenol, a group of chemicals long thought to underlie tea's healthful effects.
It is preferable not to add milk to tea. Eaten cheese wouldn't have the same effects because you don't add cheese to tea.
For other polyphenols from different sources I don't know.