When it comes to egg yolks, an ingredient that has been used in hair treatments since as early as the 11th century, the jury still seems to be out.
Here some facts:
Used as Moisturizer
Egg yolks can nourish, strengthen and heal weak strands. Egg yolks are rich in fats, including lecithin, which could help to moisturize dry hair.
Most people can use egg yolk in their hair, so long as they're not allergic or sensitive to eggs. That said, it's always a good idea to do a patch test before trying something new.
Use egg yolks in hair no more than once or twice a month.
Egg yolks work well with most other hair-healthy kitchen ingredients, like yogurt, unflavored mayonnaise, and oils.
DON'T USE WITH: Avoid using with hot water or you might "cook" the eggs in your hair.
So while the scientific community seems to be at odds when it comes to whether or not egg yolks definitively benefit hair, there's ample evidence on the side of supporters.
Potential Benefits of Egg Yolks for Hair
There is ample evidence that some substances found within egg yolks (proteins, fats, vitamins, cholesterol, etc.) are beneficial to hair. So keep in mind that the benefits listed below are not necessarily facts as much as very strong theories.
Helps moisturize and nourish hair: The protein and fats in egg yolks can help nourish hair, promote shine, and enhance softness.1
Repairs damaged hair and protect hair from further damage: The cholesterol found within egg yolks is filled with lipids that can help repair hair damage caused by color, chemical, heat, and excessive manipulation.2 The combination of folate, biotin, and vitamins A and E can help prevent further breakage and damage, says Wiley.
Stimulates hair growth: "There are some who believe egg yolks could stimulate hair growth, but there's not much evidence here," says King. "Some researchers in Japan found a peptide that is found in egg yolks to stimulate hair growth in mice, but we would definitely need more data to prove this."3
How to Use Egg Yolks for Hair
If you're interested in testing egg yolks out on hair, a DIY recipe is your best route. "Beat 2-3 eggs until frothy and then apply to the hair. Cover with a shower cap for 20 minutes. Rinse with cool water. Then shampoo and condition as usual
Apply a simple DIY mask once or twice a month to keep hair strong and soft. Follow her recipe below.
2 egg yolks
1 tablespoon unflavored mayonnaise
Combine ingredients and whip together in a bowl. Apply the mixture from roots to ends and cover with a shower cap. After 20 minutes, rinse the hair thoroughly.
Using cold water, follow with shampoo and conditioner.
Some suggest mixing egg yolks with a carrier oil (like olive or avocado oil) for easier distribution and an extra boost of fatty acids. She also suggests leaving on the mask for no more than 30 minutes, after which it might begin to harden on the hair.