Eggcetra went a popular jingle not so long ago. The bird flu must have scared everyone into staying away from chicken eggs, but it certainly doesn't mean it isn't as good for you as it was earlier. One large egg contains 300 micrograms of choline (in the yolk), and also 315 milligrams of phosphatidylcholine . Besides having a significant effect on brain function and the nervous system, choline also has an impact on cardiovascular health since it is one of the B vitamins that helps convert homocysteine, a molecule that can damage blood vessels, into other benign substances.