In a study of the German soldiers, published in January 2012, Krapohl and colleagues found significant differences between the guards with gynecomastia and a control group of healthy males without signs of gynecomastia. Those in the Guard Battalion in Berlin had lower testosterone levels and higher body mass indexes (BMI), or a measure of body fatness. (The 9 Most Bizarre Medical Conditions)
While the researchers hypothesize the mechanical stress from daily drills may be the underlying cause, they are not sure exactly how the "chest thumping" causes the breast growth. "There are no experimental studies identifying possible mechanisms at the cellular level that might induce gynecomastia mechanically," they write in the journal article, adding that these findings may provide new impetus for such studies. The research is detailed in the journal GMS Interdisciplinary Plastic and Reconstructive
Other research has shown that while gynecomastia tends to be symmetric, it can also be asymmetric; the lopsided type tends to be more common on the left side, according to a review in the Cleveland Clinic Journal of Medicine.
Over 70 percent of the German battalion's soldiers have been diagnosed with significant gynecomastia. Military officials have promised to keep an eye on the men's breasts.
"The affected soldiers are being medically supervised and treated individually," an army spokesman told the Herald.
This article originally appeared on LifesLittleMysteries.com.
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