The appearance of a grey hair strand is a normal and expected sign of aging we all experience. As we get older, we'll start to see more grey hairs on our scalp, which may signal oncoming health problems. Researchers at Cairo University in Egypt have found rapidly going grey is linked to an increased risk of heart disease, regardless of our age.

"Ageing is an unavoidable coronary risk factor and is associated with dermatological signs that could signal increased risk," said Dr. Irini Samuel, a cardiologist at Cairo University, in a statement.

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Previous research has found there are signs of physical aging that also coincide with biological aging. In a 2013 study, published in Circulation, Danish researchers found people with four signs of aging, including receding hairline at the temples, baldness at the head's crown, earlobe crease, and yellow fatty deposits around the eyelid, were about 60 percent more likely to have a heart attack, and about 40 percent more likely to develop heart disease over a 35-year period. However, hair greying and wrinkles were not linked to increased heart risks, like coronary artery disease (CAD).

CAD, the most common type of heart disease, occurs when the arteries that supply blood to the heart muscle become hardened and narrowed. This is the result of cholesterol buildup and other material, known as plaque, on the inner walls, called atherosclerosis, according to Medline Plus. As the buildup grows, there's less blood that can flow through the arteries, which means the heart muscle can't get the blood or oxygen it needs.

In the study presented at EuroPrevent 2017, Samuel and his colleagues sought to revisit the potential link between looks and heart disease by examining 545 adult men who underwent multi-slice computed tomography (CT) coronary angiography for coronary artery disease. The men were divided into several groups according to the presence or absence of CAD, and the amount of grey/white hair. Grey hair was rated using the hair whitening score: 1 = pure black hair, 2 = black more than white, 3 = black equals white, 4 = white more than black, and 5 = pure white. In addition, researchers collected data for known CAD risk factors, including hypertension, diabetes, smoking, dyslipidemia, and family history of CAD.

The findings revealed age, hair whitening score, hypertension and dyslipidemia were independent predictors of the presence of atherosclerotic coronary artery disease. Age was the only independent predictor of hair whitening. In other words, apart from chronological age, hair greying is seen as an indicator of biological age, and could be a warning sign of heart disease risk.

The researchers explain impaired DNA repair, oxidative stress, inflammation, hormonal changes, and the loss of cells' power to divide and grow, are among some of the mechanisms atherosclerosis and going grey share.

Samuel cautions their findings warrant further research, and they need to work with dermatologists to learn more about the genetic causes, and the possible environmental factors that determine hair whitening. Moreover, women weren't included in this sample.

"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" said Samuel.

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In the meantime, men at high risk of CAD should continually do check-ups, and initiate preventative therapy.

See Also:

Some Doctors Still Consider Heart Disease A 'Man's Issue,’ Fail To Track Risk In Women

Diabetes And Heart Disease Risk: Greater Danger Before Menopause