Sunny Side Up GREELEY, CO (KUNC) - It's hard to switch topics - especially when there's new information to build on what you've already talked about. That's the case for KUNC commentator Dr. Marc Ringel.

It's been exactly two weeks since my last piece aired. It was about macular degeneration. Though there are thousands of other medical illnesses I could choose to talk about, I've decided to go on some more about this one, the most common cause of blindness in Americans over 65 years-old, because a fascinating article has come across my desk since that previous commentary.

The title of this report is more than a mouthful. "Consumption of 2 and 4 egg yolks per day for 5 weeks increases macular pigment concentrations in older adults with low macular pigment taking cholesterol-lowering statins," appears in the September 16th edition of the American Journal of Clinical Nutrition. Let me explain what it's about in a number of bite-size pieces.

The authors studied 37 people over 60 years of age who had been identified at a University of Massachusetts eye clinic as having low levels of pigment in their maculae, the highest acuity spot on the retina. You may recall that the yellowish macula consists of an extra-high concentration of cones, which do their light-sensing job thanks to highly-colored photosensitive pigments.

A low concentration of macular pigment can be a sign of impending visual trouble, including macular degeneration. So it was an encouraging sign when the researchers found that eating just two egg yolks a day for five weeks significantly increased pigment levels in the subjects' maculae and that four egg yolks worked even better. Egg yolks are rich in lutein and zeaxanthin, nutrients that promote production of visual pigments.

Egg yolks are also chock full of cholesterol. When the connection was first made in the 1960s between cholesterol and coronary artery disease, cutting yolks out of the diet was a cornerstone of the nutritional advice given to patients with heart disease. And so was born the egg white omelet.

The study's authors did cover the heart disease question. They chose patients who had had high enough levels of LDL ("bad cholesterol") to have been taking statin drugs for their blood fat problems. The researchers did blood tests on the subjects, both before and after adding egg yolks to the diet. They found no ill effects in terms of absolute levels nor in terms of proportions of "good" and "bad" subtypes of cholesterol.

Let me caution you, though, before you throw out the granola or invest in an egg farm, that demonstrating an extra bit of coloration in the macula over the course of a month or so is a far cry from showing a decrease in macular degeneration and its consequences over the course of years. Still, it's heartening. Especially for an egg lover like me.
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