Chickens, humans and other animals produce a waxy substance known as cholesterol and store it in their liver and blood. Although cholesterol has a negative connotation because of its association with coronary heart disease, you need cholesterol to build healthy cells, produce vitamin D from sunlight, create bile acids that digest your food and excrete hormones that regulate sexual functioning and other body processes.
Cholesterol and Fat
A large chicken egg yolk contains 184 mg of cholesterol, along with 4.5 g of total fat. Unhealthy saturated fats make up 1.6 g of the total fat in an egg yolk, while monounsaturated fats account for 2 g and polyunsaturated fats make up 0.7 g. The white portion of this same egg, on the other hand, is cholesterol-free and contains a scant 0.6 mg of total fat, with no measurable amount of saturated fat.
Significance
A single egg yolk provides a significant amount of your daily maximum level of both cholesterol and saturated fat. The American Heart Association advises most adults to limit their cholesterol intake to 300 mg a day. If your blood level of low-density lipoprotein, or LDL, cholesterol is above 100 mg/dL, or if you already have coronary heart disease, you should stay below 200 mg of dietary cholesterol a day. The AHA also advises keeping your total fat intake between 25 and 35 percent of your calorie requirements and limiting saturated fats to less than 7 percent of total fats. On a 1,500 calorie diet, that means 375 to 525 calories of total fat and 23 to 37 calories from saturated fats. At 9 calories per gram, your saturated fat intake should stay between 2.6 and 4 g. Two egg yolks put you over the lower limit and close to the upper limit, with no allowance for other menu items.
Substitutions
A heart-healthy diet limits the amount of animal foods high in cholesterol and saturated fats, including egg yolks. When a baking recipe calls for an egg, try substituting two egg whites for the whole egg. If you're scrambling a pan of eggs for your family, toss out half of the egg yolks. You can also purchase commercial egg substitutes that are cholesterol-free.
Tips
Cooking methods make a big difference when it comes to cholesterol and fat content. If you fry two eggs in two tablespoons of butter, for example, you end up with a total of 430 mg of cholesterol and 17.8 g of saturated fat. A hard-boiled egg, on the other hand, has 184 mg of cholesterol and 1.6 g of saturated fat. Instead of piling high-fat cheeses, sour cream, bacon, sausage or other animal products on top of your scrambled eggs, add chopped tomatoes, peppers or other heart-healthy vegetables.
