Quakers have a restricted diet?

To my knowledge, Quakers have never really had any restrictions placed on their diet. I've researched a bit of Quaker history myself, and I grew up in a Quaker church, and I never encountered any rules about one's diet. The Quaker tradition had members say "thee" and "thou" instead of "you" (when Quakerism started in the 1600s, thee and thou where used when talking to people of equal status, and you was used for superiors), members would dress plainly (not in fancy clothes or heavy ornamentation), would refuse to swear oaths, and many were pacifists. But as far as I know, there's been nothing said about diet.