A new study has shown the harmful effects of hair dye in relation to primary biliary cirrhosis (PBC), an early indication of cirrhosis of the liver, often linked to psoriasis, urinary infections, and shingles.

On March 24, researchers published their findings in Gut, an international peer-reviewed gastroenterology and hepatology journal, showing that women who dyed their hair were 37 percent more likely to develop a PBC than those that did not.

The authors of the study noted they are not aware of what in the hair dye is causing this effect but speculate based on past studies that PBC can be linked to chemicals, including octynoic acid, found in beauty products like hair dye and nail polish.

Octynoic acid is also found in cigarettes and the researchers found smokers were more apt to develop PBC, as were those with a family autoimmune disease history, such as rheumatoid arthritis, thyroid and coeliac diseases.

Full case study, "Case-control studies of risk factors for primary biliary cirrhosis in 2 United Kingdom populations": www.gut.bmj.com