Damaged keratin could be repaired via a protein modification.

Shinier, healthier hair may be as close as your local Asian grocery store. A new study suggests that wheat gluten, a protein derived from wheat flour that is often used as a meat alternative, can repair damaged protein in hair. However, there may be some ambiguity in the results: More extensive testing is needed to convince other scientists. 

Keratin is a fibrous protein that accounts for majority of hair’s composition. These proteins are stitched together by chemical connections, which increases their strength and rigidity. Disulfide bridges are strong and undamaged in healthy hair. However, normal living has its drawbacks: Hair becomes brittle when the disulfide bridges are broken due to overexposure to the sun and chemical processes like bleaching, straightening, and dying.

Because of this, for decades, the hair care industry has been exploring the use of proteins derived from animals and plants as a means of repairing damaged keratin. To do so, however, calls for a delicate balancing act of chemicals. Peptides, the building blocks of proteins, are all neutrally charged at a pH value of 7. This value, known as the isoelectric point, must be similar to the pH of hair keratin in order to stimulate the production of new disulfide bonds. Shukun Wang, a chemist from Jiangnan University in Wuxi, China, claims that none of the goods on the market now are capable of doing this. 

Wang and her team were interested in adjusting the isoelectric point of a protein so that it would be more stable at the same pH as keratin. Wheat gluten was chosen for the experiment because it is a cheap and readily available source of protein for industrial use. The scientists began by dissolving Alcalase, an enzyme that aids in protein digestion, into water and soaking their gluten in the mixture. They then put it into a brew of chemicals known as EDDAC, which raised the isoelectric point of the whole thing. Finally, they used the solution as an ingredient in a shampoo and combed it through newly cut human hair, both wet and dry. 

A machine measured friction as a surrogate for damage from combing since damaged hair creates more friction than healthy hair. Researchers describe their findings in today’s issue of Royal Society Open Science. They found that treated hair reduced friction by roughly 21% when dry and by nearly 50% when wet, compared to untreated hair from the same person. The results of a scanning electron microscope examination of the hair corroborated those observations. Compared to untreated hair, treated hair fibres were noticeably smoother, leading scientists to conclude that the mixture encouraged the broken-down wheat gluten to create new bonds that replaced the destroyed ones.

The linked statistical analyses seem “inadequate,” says Sarah Millar, a dermatologist who studies hair at the University of Pennsylvania Perelman School of Medicine, un an email to Science. Important details, such as the hair type evaluated and the method used to ensure uniform combing force throughout studies, are absent from the study.

Millar claims the method has promise for consumers seeking cosmetics backed by science, but only if the results keep up. Consumers may be assured that the products they buy have been shown to deliver on their claims thanks to “if properly conducted and controlled” studies like these. Maybe it’s not a matter of genetics after all.