Bald men have a higher risk of developing heart disease than men with a full head of hair - but only those who are thinning on top rather than men with a receding hairline, a new study suggests Thursday. Researchers from Japan found that men who had lost most of their hair were a third more likely (32 percent) to develop coronary heart disease (CHD) than those who retained a full head of hair. Bald or extensively balding men aged between 55 and 60 were 44 percent more likely to develop coronary artery disease, according to the study published in the online journal British Medical Journal. The researchers from Japan examined six studies, including three studies that tracked the health of balding men for at least 11 years, involving 37,000 men. They found that the link between CHD and baldness depends on the severity of the baldness. Severe baldness on the top or crown of the head, also known as the vertex, was associated with a 48 percent increased risk while moderate vertex baldness and mild vertex baldness were linked to a 36 percent and 18 percent risk respectively. The authors also looked at differing grades of baldness - frontal, crown-top and combined. Men with both frontal and crown-top baldness were 69 percent more likely to have CHD than those with a full head of hair, while those with just crown-top baldness were 52 percent more likely to do so. Those with a receding hairline were 22 percent more likely to develop the disease. The authors note that the explanation of the link is \"unclear\" but say that it has been previously suggested that classical coronary risk factors such as age, hypertension and smoking might influence both conditions. They also say that baldness has previously been linked to insulin resistance, metabolic syndrome and hypertension. However, it has been suggested that male pattern baldness has been linked to coronary heart disease through chronic inflammation or increased sensitivity to testosterone. Doireann Maddock, senior cardiac nurse at the British Heart Foundation, said: \"Although these findings are interesting, men who\'ve lost their hair should not be alarmed by this analysis. \"Much more research is needed to confirm any link between male pattern baldness and an increased risk of coronary heart disease. \"In the meantime, it\'s more important to pay attention to your waistline than your hairline. \"Hereditary hair loss may be out of your control, but many of the risk factors for coronary heart disease are not. \"Stopping smoking, maintaining a healthy weight and being as active as possible are all things that you can do to help protect your heart.\"