A source of all essential amino acids and complete protein, hard-boiled eggs provide necessary vitamins, minerals and phytonutrients such as riboflavin, B12, pantothenic acid, folate, phosphorus, selenium, zinc, choline, vitamin D, lutein and zeaxanthin. A large egg supplies 78 calories, 5.3 g of total fat and 6.3 g of protein. Because a cholesterol content of 213 mg is contained in the yolk, more than one egg consumed per day exceeds the recommended 300 mg maximum daily intake for cholesterol. This limits the quantity of eggs you may eat on a low-cholesterol, heart-healthy diet.
Protein
Egg protein, a complete protein, provides all essential amino acids that the body requires. Diet must provide these amino acids because the body cannot synthesize them. One large egg provides 6.3 g of protein. The white and yolk contain 3.6 g and 2.7 g of protein, respectively. A daily protein intake of .8 g per kg of body weight is recommended for most people, although athletes and pregnant or lactating women need more.
Cholesterol
Dietary cholesterol is found in animal products such as meat, dairy and eggs. A heart-healthy diet includes a diet low in cholesterol, total fat, saturated fat and sodium. The yolk of one hard-boiled egg contains approximately 213 mg of cholesterol, or 71 percent of the 300 mg maximum daily recommended intake. If you have high low-density lipoprotein cholesterol or take cholesterol medication, one egg yolk exceeds your daily cholesterol maximum of 200 mg.
Lutein and Zeaxanthin
One large egg yolk contains 176 micrograms of lutein and zeaxanthin, antioxidants found in the lens and retina of the human eye. Lutein and zeaxanthin may help prevent common causes of age-related blindness and slow the development of age-related macular degeneration and cataracts. Whole eggs contain 5.3 g of fat, which may increase bioavailability of these carotenoids, as they are better absorbed with fat in a meal. In the August 2004 issue of the "Journal of Nutrition," researchers from Tufts University reported that the bioavailability of lutein from lutein-enriched eggs was significantly higher than from spinach or lutein supplements.
Choline
The yolk of one hard-boiled egg provides 112.7 mg of the essential nutrient choline. Daily recommended choline intake requirements for adult men and women are 550 mg and 425 mg, respectively. One egg provides 20.5 percent of this requirement for men and 26.5 percent for women. Choline is needed for production of the neurotransmitter acetylcholine, proper nerve and brain function, fetal brain development and to synthesize phosphatidylcholine, a molecule that prevents fat and cholesterol accumulation in the liver. A choline derivative, betaine, may help reduce risk of cardiovascular disease by helping to lower homocysteine levels.
Heart-Healthy Options
A cholesterol content of 213 mg in the yolk limits the quantity of eggs consumed per day on a heart-healthy diet. Meal items such as scrambled eggs, omelets or baked goods may be prepared with an increased ratio of white to yolk in effort to reduce cholesterol intake. An omelet made with three egg whites and one yolk reduces the cholesterol content from 639 mg to 213 mg. Protein content is also reduced by 5.4 g. Additional fresh herbs or spices may enhance flavor.
References
- Incredible Egg: It's All In an Egg
- USDA Nutrient Database: Egg, Whole, Cooked, Hard-Boiled
- American Heart Association: Common Misconceptions About Cholesterol
- Medline Plus: Protein in Diet
- USDA Nutrient Database: Egg, White, Raw, Fresh
- Institute of Medicine: Dietary Reference Intakes: Protein and Amino Acids
