The sunny side of eggs

EGGS are cracking open some nutritional barriers.

After decades of being out of favor because of their high cholesterol content, eggs are earning high marks as a low-cost source of protein. They pack key vitamins and minerals, including iron. They’re a good source of lutein, which may help protect vision. They’re low in saturated fat, have no trans fat and provide some healthful fat.

“Eggs certainly can be part of a healthy diet,” says American Heart Assn. President Robert Eckel, who cautions that even so, consumers still need to track how much cholesterol they eat.

Foods high in saturated and trans fatty acids, such as fried foods, are the biggest contributors to increased blood cholesterol levels. But studies have also shown that eating an egg a day leads to about a 1% to 3% increase in blood cholesterol levels.

Large population studies show more mixed results for egg consumption. Some point to an increased risk of heart disease. Others show no risk and even a possible benefit. But more recent research suggests an additional, independent risk of heart disease from eating high-cholesterol foods such as eggs. That indicates, Eckel says, “that dietary cholesterol may increase the risk of heart disease by a mechanism that we do not yet understand.”

That’s why the current advice from U.S. government agencies and medical groups alike is to limit cholesterol intake to 300 milligrams daily, even for those whose blood cholesterol levels are normal. People who already have high blood cholesterol, heart disease or diabetes are urged to keep cholesterol intake to 200 milligrams or less per day.

Because that’s about what one large egg contains, “it makes it real difficult to incorporate more than one egg a day,” said Penny Kris-Etherton, professor of nutrition at Pennsylvania State University.

Not all scientists agree that healthy people need to restrict eggs or other high-cholesterol foods. In Australia and Canada, health guidelines recommend no upper limit on daily cholesterol intake for the healthy population.

The National Heart Foundation, Australia’s equivalent of the American Heart Assn., recently awarded eggs a Heart Tick, a check-mark symbol that’s reserved for heart-healthy food. As to how many eggs should be eaten, the foundation notes that it “does not restrict consumption of eggs for the general population. For healthy people, the best guide is to include a wide variety of nutritious foods, including eggs.”

But the foundation does encourage people who have high blood cholesterol levels or heart disease to seek additional dietary advice from health professionals before eating eggs or other high-cholesterol foods.

“Identifying the egg as the source of other nutrients is meritorious,” said Eckel, of the American Heart Assn. “But dietary cholesterol is not necessary for health, and we certainly don’t want to add a potentially injurious [food] substance at unlimited levels.”

In the meantime, here’s what you need to know about eggs and cholesterol:

* Skip the yolk whenever possible. That’s where all the cholesterol is in the egg. An egg white, on the other hand, has nearly 4 grams of protein, and no fat or cholesterol. So cut cholesterol intake by using one yolk for every two to three whites when you make scrambled eggs or omelets. In baking, you can also substitute two whites for a whole egg. Other options: Use egg substitutes, or look for cartons of pourable egg whites available in many grocery stores.

* Hedge your bets. If you add eggs or other cholesterol-rich foods to your daily fare, get a blood cholesterol test now and another in two to three months to see if your levels have changed. Individual response to eating high-cholesterol food can vary widely.

* Track other sources of cholesterol in your diet. Organ meats (liver, kidney, brains) are also very high in cholesterol. Crab, shrimp and squid contain moderate amounts of cholesterol. A quarter pound of shrimp, for example, has about the same amount of cholesterol as an egg yolk.

Whenever possible, avoid fried fish, which adds saturated and sometimes trans fats. If you do eat high-cholesterol foods, keep saturated fat low and add a little bit of healthful fat, such as canola oil, which can help blunt the cholesterol’s effects.

* Look at the big picture. One meal or one day of high-cholesterol food probably will not affect your blood cholesterol levels.

“Focus on your overall lifestyle, not on single food items,” says Neil Stone, professor of medicine at Northwestern University. “The two biggest things people can do diet-wise are: No. 1, to limit saturated fat and trans fats; and No. 2, to avoid becoming overweight.”