The Incredible, Edible Egg

Eggs are a near perfect food all wrapped up in one single cell. Eggs contain the most complete and highest protein rating of any food. Two eggs contain more than twelve grams of protein, just over half in the white and the rest in the yolk. In addition, eggs also contain many essential nutrients, including significant amounts of vitamins A, D, E, B1, B2, B6, folic acid, and especially vitamin B12. Eggs also contain important minerals including calcium, magnesium, potassium, zinc, and iron. Choline and biotin, also important for energy and regulation of stress, are contained in large amounts in eggs. Most of these nutrients are found in the yolk.

The fat in egg yolks is also nearly a perfect balance, containing mostly monounsaturated fats and about 36 percent saturated fat. Additionally, egg yolks contain linoleic and linolenic acids—both essential fatty acids. Eggs have almost no carbohydrate (less than one gram), making them the perfect meal or snack for the millions who are carbohydrate intolerant. Ounce per ounce, eggs are also your best food buy with hardly any waste. And, with so many ways of cooking them, eggs are delicious and quick to prepare. For most people, eggs can be part of a healthy food plan; I eat several whole eggs a day.

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While most people love the taste of eggs, many are still concerned about eating them because of cholesterol—it’s one of the most misunderstood subjects related to heart disease. Abnormally high levels of cholesterol can be a risk factor for heart disease, although your total cholesterol is not the best—or only—measure for heart-disease risk. Many people who die of heart disease have normal total cholesterol numbers, and many with high cholesterol never develop heart disease.

Perhaps the greatest misconception about cholesterol is that eating foods containing it significantly raises levels in the blood. In truth, most studies have shown that eating cholesterol does not alone substantially increase blood-cholesterol levels. Moreover, some studies show that not eating cholesterol can prompt your body to make more—and that eating eggs can improve your cholesterol numbers!

While there is a correlation between higher total cholesterol in the blood and incidences of heart attacks, evaluating cardiac risk calls for a complete fasting blood-lipid profile that measures at least total, HDL (high-density lipoprotein), and LDL (low-density lipoprotein) cholesterol, and triglycerides.

The most important thing to know about cholesterol is that cholesterol itself isn’t “bad,” but rather something to be kept in balance. It’s also important to understand that most of the cholesterol in the bloodstream is actually made by your liver. If you eat more cholesterol, your body prompts the liver to make less of it. But if you take in less, your liver makes more. That’s why many people on a low-cholesterol diet still have high blood-cholesterol levels.

Actually, all cells in the body—including those of the heart—make cholesterol every day. That’s because cholesterol is necessary for many essential processes that keep us healthy. For example, the outer surfaces of cells contain cholesterol that helps regulate which chemicals enter and exit. Cholesterol is also used to make many hormones, including sex hormones and those that control stress. Cholesterol is also a key component of the brain and nerve structure throughout the body, and a key compound in the skin, allowing us to make vitamin D from the sun.

HDL cholesterol is called “good” cholesterol because it protects against disease by removing accumulated deposits of cholesterol and transporting them back to the liver for disposal. So, higher HDL numbers are generally healthier. It’s best if you can divide your total cholesterol figure by your HDL number and get a ratio below 4.0, which is about the average risk for heart disease. Aerobic exercise, monounsaturated fats, fish oil, and moderate alcohol can increase HDL. Excess stress and anaerobic exercise, hydrogenated fats, and excess consumption of saturated fats and refined carbohydrates lower it.

More importantly, the recommendation that people substitute polyunsaturated fats for saturated can be devastating for HDL levels. If the ratio of polyunsaturated fat to saturated fat exceeds 1.5, HDL levels usually diminish, raising your cardiac risk. If your fats are balanced, as discussed in the next chapter, you avoid raising your ratio above 1.5.

LDL cholesterol is known as the “bad” cholesterol. A recent trend in preventative medicine is to stress lowering LDL cholesterol with drugs. But it’s really not the LDL itself that causes the potential harm or risk. It’s only when the LDL oxidizes that it deposits in your arteries. Oxidation of LDL results from free radicals, in much the same way that iron rusts. While lowering LDL levels can make less of it available for oxidation, antioxidants from fruits and vegetables can help prevent oxidation. In addition, many of the factors just mentioned that raise HDL also lower LDL, which is best measured when blood is drawn after a twelve-hour fast for an accurate evaluation.

Excess dietary carbohydrates can especially adversely affect LDL levels. This is due to excess triglycerides from carbohydrates producing more, smaller, denser LDL particles, which are even more likely to clog arteries.

In addition, a lower intake of dietary cholesterol is linked to an increase of these more dangerous LDL particles. And to make matters worse, these types of LDL particles are also associated with the inability to tolerate moderate to high levels of dietary carbohydrates (i.e., insulin resistance) even in relatively healthy individuals.

One of the worst scenarios for your cholesterol is if the HDL is lowered while the LDL and total cholesterol are elevated. Hydrogenated and partially hydrogenated fats (trans fats) do this, and many experts now consider the intake of hydrogenated fat to be a risk factor for heart disease. So avoid margarine and products containing this dangerous substance.

Eating too much saturated fat can raise LDL and total cholesterol levels. The worst offenders may be dairy foods such as butter, cream, cheese, and milk. Red meat such as beef, while it does contain saturated fat, can actually improve cholesterol levels. This is partly because, just as in eggs, about half the fat in beef is monounsaturated. Grass-fed beef has the best balance of fats compared to most beef, which is corn-fed. In addition, much of the saturated fat in beef is stearic acid, a fatty acid that won’t raise cholesterol and may actually help reduce it. (The fat in cocoa butter also contains high amounts of stearic acid.)

Fiber and fiber-like substances are also an important factor in decreasing total cholesterol and improving total cholesterol/HDL ratios. Most people don’t eat enough fiber, especially from fresh vegetables and fruits. Eating at least one large raw salad daily in addition to cooked vegetables and one to three servings of fresh fruit or berries—totaling eight to ten servings—will provide significant amounts of fiber. These foods also provide natural phytosterols, which help reduce cholesterol and may be the reason early humans, who ate very large amounts of saturated fat, were well protected.

Back to eggs. Do you avoid eating eggs because you fear they will somehow raise your blood cholesterol to dangerously high levels? The fact is that eating eggs won’t necessarily raise your total cholesterol. After decades of medical research, studies have never linked egg consumption to heart disease. Stephen Kritchevsky, PhD, director of the J. Paul Sticht Center on Aging at Wake Forest University, states, “People should feel secure with the knowledge that the [medical] literature shows regular egg consumption does not have a measurable impact on heart disease risk for healthy adults. In fact, many countries with high egg consumption are notable for low rates of heart disease.”

Eggs are only as healthy as the hens that lay them, since the nutritional make-up of eggs, especially the fat, depends upon what the chickens eat. For this reason you should avoid run-of-the-mill grocery-store eggs that have been produced in chicken factories. Unfortunately this includes most eggs on the market. The healthiest eggs come from organic, free-range hens. Even better: buy eggs from a local farmer who lets chickens eat healthy, wild food and organic feed. Local free-range usually means that the hens are allowed to roam where they can eat bugs and vegetable matter, yielding more nutritious eggs. So-called omega-3 eggs come from chickens fed flax seeds. Often these hens are neither free-range nor certified organic and are still housed in very crowded hen factories.