Spence is concerned that people do not know just how much cholesterol is in one egg yolk. "For people who are at high risk for heart attacks and strokes the recommended amount of cholesterol is below 200 mg a day and one large egg yolk has 210 mg of cholesterol--there is more cholesterol in one egg yolk than the total recommended daily intake of cholesterol," he said. "To put that in perspective, one egg yolk has more cholesterol than a Hardee's Monster Thickburger which contains 12 ounces of beef, three slices of cheese, and four slices of bacon. I know the burger is worse than the egg because it also has saturated fat but the cholesterol per se is harmful and in fact, cholesterol is permissive of the harmful effects of saturated fats."

As such, Spence recommends switching to egg whites or to egg-substitutes and eating a diet that is low in animal fats and low in cholesterol. "I tell my patients to learn how to make a nice tasty omelet or frittata with egg whites, or--what I like even better--is a carton of scrambled eggs with no cholesterol. They're called Egg Beaters, or Better-n-Eggs," Spence said.

"Oh come on. You can get those nutrients a lot safer if you eat them in other foods that aren't loaded with cholesterol."

Better-n-Eggs is an egg substitute product that contains 98 percent egg whites and includes these additional ingredients: corn oil, water, natural flavors, sodium hexametaphosphate, guar gum, xanthan gum, color (includes beta carotene).

Is Spence concerned about the various additives and the processing that goes into these types of products? "No. I'm more concerned about the cholesterol in eggs."

It's worth pointing out that many of the nutrients found in eggs are found in the yolk. Among many other nutrients, egg yolk contains lecithin, which helps the body digest fat and metabolize cholesterol; betaine and choline which lower homocysteine levels; glutathione, which helps fight cancer and prevents oxidation of LDL; lutein and zeaxanthin, which have been shown to prevent colon cancer; and biotin, a B vitamin crucial for healthy hair, skin, and nerves.

I asked Spence what he thought about the various nutrients found in egg yolks -- if we eliminate eggs from our diets won't we be missing out on these nutrients? "Oh come on," he said. "You can get those nutrients a lot safer if you eat them in other foods that aren't loaded with cholesterol. There are no nutrients in the egg yolk that you need."

The MIT researcher Stephanie Seneff would beg to differ. In fact, research she is currently working on shows that one crucial nutrient -- sulfur, which egg yolks contain in very high amounts -- may be the underlying deficiency to our collective problems with cholesterol and heart disease. "The key to everything may just be sulfur," Seneff says.

Sulfur is a mineral found in several foods, including vegetables like broccoli, cauliflower, Brussels sprouts, garlic, and kale. It is also found in very large amounts in animal proteins -- one of the best-known sources is egg yolk. When sulfur combines with four oxygen molecules, it becomes sulfate. Sulfate is combined with cholesterol to produce cholesterol sulfate in large amounts when our skin is exposed to sunlight as well. Sulfation is important to enable cholesterol transport to all the tissues.

The research Seneff and her team are working on is a complete reevaluation of our understanding of cholesterol and its role. It's a fairly complex biological process but put simply, Seneff believes that the build up doctors find in arteries is "cholesterol trapped in the wrong place," or cholesterol trapped in the plaque. The reason it's trapped in the plaque is because the LDL is damaged from excess sugar in the blood. As a result of our highly processed, starchy, sugary diets, many Americans have excess blood sugar. Once the sugar has damaged the LDL it cannot go back to the liver where the cholesterol would be processed and recycled back into the body. The plaque then builds up in the arteries, where it "waits for the opportunity to become cholesterol sulfate, which all of the body's systems need," Seneff says. "The bottleneck is the sulfate. Cholesterol needs sulfate to be mobile. The damage then is a consequence of lack of cholesterol and lack of sulfate."

This may be why a much larger study in The Journal of the American Medical Association found "no overall significant association between egg consumption and heart disease." In fact, the study of 118,000 people found that those who ate five or six eggs per week had significantly lower mean serum cholesterol levels than those who ate one egg per week. Plus, the daily nutrient intake of people who ate eggs was much higher than the non-egg eaters.

In the public imagination, cholesterol is the villain whose only function is to clog up arteries. "This is the complete wrong picture," Seneff says. "It's very easy to imagine plaque build up -- but it's not the correct picture. Cholesterol is vital -- it is a precious substance in our bodies. Cholesterol is to animals what chlorophyll is to plants."

Are we to increase our consumption of egg yolks as Seneff suggests or completely eliminate them as Spence advises? What we need are clear guidelines, not influenced by industry, that present a straightforward approach to weight loss and a healthy body. The simplest answer currently available is to eliminate processed foods from our diets -- the saturation of processed foods into our diets tracks most closely with the rise in obesity and diet-related disease in this country. So when presented with confusing dietary advice or questions while food shopping ask yourself this simple question: What's my least processed option? Take that one.