Eggs deliver all the amino acids our body needs to build protein, and both hair and nails are made from a protein called keratin. An extra-large egg contains seven grams of protein, which is equivalent to one ounce of meat, fish or poultry. In general, adults are advised to consume five to eight ounces of meat, poultry, fish, egg or other protein alternatives daily.
Eggs also contain biotin—a key nutrient for maintaining healthy hair and nails. Eggs should be eaten cooked, as avidin found in raw egg whites can interfere with biotin absorption. Cooking denatures avidin, making sure biotin is absorbed in the gut. Other foods that contain biotin include beef liver, salmon and sweet potatoes.