Men with more grey hair - irrespective of age - may be at increased risk of heart disease, warns a new research. "Our findings suggest that, irrespective of chronological age, hair greying indicates biological age and could be a warning sign of increased cardiovascular risk," said Irini Samuel, a cardiologist at Cairo University, Egypt.
Atherosclerosis, build-up of fatty material inside the arteries, and hair greying share similar mechanisms such as impaired DNA repair, oxidative stress, inflammation, hormonal changes and senescence of functional cells.
"Atherosclerosis and hair greying occur through similar biological pathways and the incidence of both increases with age," Samuel added.
The researchers assessed the prevalence of grey hair in patients with coronary artery disease - usually caused by atherosclerosis -- and whether it was an independent risk marker of disease.
The amount of grey hair was graded using the hair whitening score - one referring to pure black hair, two to black more than white, three to black equals white, four to white more than black, and five to pure white.
Data was collected on traditional cardiovascular risk factors including hypertension, diabetes, smoking, dyslipidaemia and family history of coronary artery disease.
The researchers found that a high hair whitening score (grade three or more) was associated with increased risk of coronary artery disease independent of chronological age and established cardiovascular risk factors.
Patients with coronary artery disease had a statistically significant higher hair whitening score and higher coronary artery calcification than those without coronary artery disease.
"A larger study including men and women is required to confirm the association between hair greying and cardiovascular disease in patients without other known cardiovascular risk factors," Samuel said.
"Further research is needed, in coordination with dermatologists, to learn more about the causative genetic and possible avoidable environmental factors that determine hair whitening," she added.