A remarkable study just published in the very influential American Journal of Clinical Nutrition examined the effects of eggs on the risk of heart attack and stroke in middle-aged and older men.

Egg yolks contain high concentrations of saturated fats and cholesterol, and for years it has been assumed that too many eggs would increase cholesterol levels, predisposing egg lovers to heart attacks and strokes. The results of this new study not only challenged the traditional thinking but also illuminated some very surprising effects of long-term egg consumption.

This study followed the health of 21,000 male physicians for 20 years. At the beginning, the average age of participants was 54. Each year, the men filled out a questionnaire in which they described their physical activity; their health conditions, including the presence of diabetes or high blood pressure; and whether they took aspirin.

They also listed their egg, vegetable and cereal consumption. Men who consumed up to six eggs weekly tended to be older, heavier and had higher cholesterol levels. Remarkably, despite the heavy consumption of eggs, these participants experienced no increase in the risk of heart attack or stroke, nor did it affect overall health.

But for reasons that are totally unexplained, those who consumed seven or more eggs weekly were 23 percent more likely to die of any cause during the study, and the risk was particularly high in diabetics. In other words, heavy egg eaters were more likely to die from cancer, lung disease and even motor vehicle accidents.

This is not the first time that research has shown similar findings. For more than 30 years, we have known that lowering cholesterol by the use of medications, such as statins, dramatically decreases the risk of heart attack and stroke, but it does not prolong life expectancy. Patients who stave off heart disease just die of other causes.

Before egg lovers everywhere revolt, it is important to analyze the details of this study. First and foremost, the results confirm that reducing the risk of one disease does not necessarily mean a longer life. So focusing solely on one medical concern is not the best approach.

Furthermore, just because a study shows a statistically significant difference between one group and another (egg eaters vs. egg abstainers), that does not mean that it is important or of any relevance.

What exactly does a 23 percent increased risk of death in egg eaters mean? Let's assume that the number of individuals dying in the group who did not eat eggs averaged one per 1,000 individuals per year. Then a 23 percent increase in risk of death means that 1.23 per 1,000 individuals would die annually in the group eating a large number of eggs weekly. Simply put, the difference is not of great relevance.

Many research studies purport to show a significant benefit or disadvantage of a certain food, intervention or medication. But that does not mean the study is of any importance whatsoever. Remember, statistics can be misleading.

Let's look a little more closely at this study on eating eggs. Eggs are a great source of protein, but they contain a great deal of cholesterol. They are extremely nutritious, containing many other valuable nutrients. And most importantly, eggs are very cheap. In areas of the world where malnutrition is epidemic, eggs can save lives. And in the United States, it is quite clear that eggs can constitute a valuable component of a healthy lifestyle.

An egg a day may not be unhealthy, particularly if it is a part of a heart-healthy diet that includes the right fats (olive and canola oils and a small serving of nuts as a source of omega-3 fatty acids), the right protein (lean meat and fatty fish), all the fruits and vegetables you want, and moderate starch consumption. A diet such as this will lower the risk of many illnesses and conditions, including cancer, heart disease and diabetes.

On the other hand, if the high-egg diet also includes hefty servings of red meat, fried foods, loaded baked potatoes and rich desserts, your cholesterol will be high, you will be overweight, and your risk of early death will increase.

Bottom line: An egg a day is fine if it's part of a plan promoting a healthy life. Be an educated consumer of health care, and make sure you understand how to interpret any research study.

Dr. David Lipschitz is the author of the book "Breaking the Rules of Aging." To find out more about Dr. David Lipschitz and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate Web page at www.creators.com. More information is available at www.drdavidhealth.com.

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