testosterone

Low levels of iron in the blood may indicate a serious but treatable medical condition if caught early, but patients in a testosterone trial were not informed, a bioethicist finds.

Several studies out this week show mixed results for testosterone replacement. It appears to protect bone density and strength and prevent anemia, but there is no effect on memory and cognition.

A man's testosterone level drops as he ages, but boosting it with supplements has been controversial. The first year of data from a big study now suggests a modest boost in libido for some men.