A research review published recently in Nutrition Today(1) says that the high-quality protein in eggs makes a valuable contribution to muscle strength, provides a source of sustained energy and promotes satiety. High-quality protein is an important nutrient for active individuals at all life stages, they say, and while most Americans consume the recommended dietary allowance (RDA) for protein, additional research suggests that some Americans are not consuming enough high-quality protein to achieve and maintain optimal health.(2,3,4)
The Nutrition Today review analyzes more than 25 protein studies and concludes that the all-natural, high-quality protein in eggs contributes to strength, power and energy in the following ways:
- Sustained energy: The protein in eggs provides steady and sustained energy because it does not cause a surge in blood sugar or insulin levels, which can lead to a rebound effect or energy "crash" as levels drop. Eggs are a nutrient-rich source of high-quality protein and provide several B vitamins required for the production of energy in the body, such as thiamin, riboflavin, folate, B12 and B6.
- Muscle strength: Dietary protein intake directly influences muscle mass, strength and function in people of all ages. One egg provides more than six grams of high-quality protein (13 percent of the Daily Value), which can help individuals build and preserve muscle mass, and help older adults prevent muscle loss. Eggs are also rich in leucine, an essential amino acid that contributes to the muscle's ability to use energy and aids in post-exercise muscle recovery.
- Gold-standard protein: The high-quality protein in eggs provides all of the essential amino acids our bodies need to build and maintain muscle mass. In fact, the quality of egg protein is so high that scientists frequently use eggs as the standard for evaluating the protein quality of other foods.(5)
"While many Americans may be getting enough protein, they need to focus on consuming sources of higher-quality protein. Our review of the science suggests that eggs are an ideal protein choice, plus, they are very affordable," says Donald K. Layman, Ph.D., co-author of the research review and professor emeritus at the Department of Food Science and Human Nutrition at the University of Illinois. "In addition, individuals should focus on when they consume high-quality protein. Most protein consumption occurs in the evening, even though there are significant benefits to consuming more protein at breakfast, such as stimulation of muscle protein synthesis and long-lasting satiety."
They say the high-quality protein in eggs provides additional benefits, including:
- Satiety&Weight Management: A 2008 study showed that eating two eggs for breakfast helped overweight dieters lose 65 percent more weight and feel more energetic than those who ate a bagel breakfast of equal calories and volume.(6) Another recent study found that when individuals ate high-quality protein foods for breakfast, including eggs, they had a greater sense of fullness throughout the day compared to when they ate more protein at lunch or dinner.(7)
- Value & Versatility: In addition to providing high-quality protein, eggs are affordable and versatile. Serving for serving, eggs cost less than other sources of high-quality protein. For an average of just 15 cents per egg, Americans get a number of important nutrients in addition to high-quality protein, including choline, riboflavin and vitamin B12, all for only 70 calories per egg.
(1) Layman DK, Rodriguez, NR. Egg Protein as a Source of Power, Strength and Energy. Nutr Today. 44(1):43-48.
(2) Wolfe RR, Miller SL. The Recommended Dietary Allowance of Protein: A Misunderstood Concept. JAMA 2008: 299(24):2891-2893.
(3) Fulgoni VL. Current protein intake in America: analysis of the National Health and Nutrition Examination Survey, 2003�. AJCN 2008; 87(5): 1554S-1557S.
(4) Paddon-Jones, D, et al. Role of dietary protein in the sarcopenia of aging. AJCN 2008; 87: 1562S-1566S.
(5) The use of biological value of protein in evaluating its quality for human requirements. Joint FAO/WHO/UNU Expert Consultation on Energy and Protein Requirements. 1981.
(6) Vander Wal JS et al , et al. Egg breakfast enhances weight loss. Int J of Obesity 2008: 32(10):1545-1551.
(7) Leidy HJ, et al. Increased dietary protein consumed at breakfast leads to an initial and sustained feeling of fullness during energy restriction compared to other meal times. British J of Nutr, published online September 2008.