If not for their high cholesterol content, eggs could be considered a nearly perfect food: an excellent source of complete protein (in the whites only), a source of all the essential vitamins except vitamin C and niacin, and a good source of many needed minerals, especially iron and iodine, all at a caloric bargain of 160 calories in two large eggs.
But eggs need not have a downside. Various manipulations, from extracting some of the cholesterol in the yolk to replacing the yolk with a cholesterol-free substitute, have resulted in eggs that can be eaten without concern by nearly everyone.
It is also possible to change the constituents of eggs by manipulating the diet fed to chickens. For example, when American chickens are given feed that contains fish meal or flax, they produce eggs with higher amounts of healthful fatty acids.
Still another concern about eggs involves their ability, when consumed raw or minimally cooked, to transmit the food-poisoning bacterium Salmonella, which can be fatal to people who are very old or very ill.
This has resulted in advice not to use raw eggs to make things like mayonnaise, Caesar salad and uncooked sauces, and to cook all egg dishes thoroughly.
However, according to the U.S. Department of Agriculture, eggs that are soft-boiled can be eaten safely, as long as the egg is cooked at 140 degrees Fahrenheit for 3-1/2 minutes. This kills the bacteria, yet leaves the egg soft enough to use in dressings like mayonnaise and sauces.