Joico Moisture Recovery Treatment and human hair keratin
Keratin is a protein that is a major component in skin, hair, nails and teeth. Depending on the various amino acids that combine to form keratin, it can be inflexible and hard (toe nails) or soft (skin). The surfaces of hair, skin and nails are mostly dead cells, which are shed as new cells push up from underneath. If the dead cells are kept in good condition, they will serve as an insulating layer to protect the delicate new keratin below them. Keeping the external layer of keratin moisturized will prevent cracking and splitting.
The hydrolyzed keratin in shampoos and other hair care treatments seems mostly to come from wool (which I suppose is hair to a sheep). Joico says it found a way to "capture" human hair keratin and that this is best way to ensure a match with the hair's 18 amino acids.
Since Joico made this invention 30 years ago and no one else (that I could find) has worked out how to do it, I am tempted to conclude that Joico hasn't exactly bottled human keratin. Nor I have I found any research about replenishing human keratin. Furthermore, hardly anything was known about human hair keratin until very recently. In 2004, scientists discovered that there were 15 different types of keratin in human hair.
More likely perhaps, is that Joico has put together amino acids in proportions that are similar to those in human keratin. Which is fine by me. In fact, FNS's hair growth booster serum, which I am currently testing, contains all 18 amino acids.
Water , Cetearyl Alcohol , Behentrimonium Chloride , Dimethicone , Distearyldimonium Chloride , Steareth-2 , Hydrolyzed Human Hair Keratin, Laurdimonium Hydroxypropyl Hydrolyzed Human Hair Keratin , Chlorella Vulgaris Extract , Hydrolyzed Algin , Sea Water , Camelina Sativa Seed Oil , Simmondsia Chinensis (Jojoba) Seed Oil , Vitis Vinifera (Grape) Seed Oil , Guar Hydroxypropyltrimonium Chloride , Amodimethicone , Diisopropyl Sebacate , Diisostearyl Fumarate , Glycerin , EDTA , Methylparaben , Propylparaben , Diazolidinyl Urea , Fragrance , Red 40 (CI 16035) , Yellow 5 (CI 19140)