Men losing their hair may have bigger concerns than looking like George Costanza. A new study finds that balding men share a greater risk of having a heart attack.
The more hair lost, the more serious the risk.
After reviewing six studies with a total of almost 37,000 participants, researchers found no connection to heart disease for men with a receding hairline.
But men who had lost most of their hair were 32 percent more likely to develop coronary artery disease than their friends who managed to hang onto their hair.
The researchers' findings - at the University of Tokyo, but including four U.S. sample groups - were published this week in the online UK journal BMJ Open.
When the analysis looked only at men under 55, a similar pattern emerged.
Bald or balding men were 44 percent more likely to develop the disease.
Time and again, researchers verified that the severity of baldness was related to the level of risk of coronary heart disease among various age groups.
The same goes for different balding patterns, with some variation.
Men with both frontal and crown-top baldness were 69 percent more likely to develop coronary artery disease than those with a full head of hair.
Those with just crown-top baldness were 52 percent more likely to do so. Those with just frontal baldness were 22 percent more likely to develop heart problems.
Researchers offered various explanations for their findings.
They said that baldness may indicate insulin resistance, a precursor to diabetes; a state of chronic inflammation; or increased sensitivity to testosterone.
All of which are connected either directly or indirectly with the promotion of heart disease, according to a press release. However, they concluded:
"[Our] findings suggest that vertex baldness (balding at the crown) is more closely associated with systemic atherosclerosis than with frontal baldness."
"Thus, cardiovascular risk factors should be reviewed carefully, especially by younger men [who should] probably be encouraged to improve their cardiovascular risk profile."