Eggs are rich source of nutrients except vitamin C. One egg contains 6 grams of high-quality protein and all 9 essential amino acids. Egg protein has high biological value. It has biological value of 100. One medium size egg contains 214 mg of cholesterol. The cholesterol present in egg yolk may be harmful for diabetes, cardiovascular, obesity and diabetes. Phosphorus and iodine present in egg is essential for making thyroid hormones. Egg is a good source of glutamine. Raw egg is not good for health as raw egg contains avidin and it binds with biotin and makes the vitamin unavailable. Avidin is destroyed by cooking the egg. Egg is a good source of albumin. Egg fat is highly emulsified. Eggs are rich in vitamin B12. One large egg provides 75 kcals. Choline present in eggs is helpful in fetal brain development. Eggs are of immense benefit for eyes. According to one study, an egg per day may prevent macular degeneration due to its carotenoids contents specifically lutein and zeaxanthin.   Lutein may lower risk of developing cataracts.