Nearly one-third of women experience heavy periods each month. This means that unlike normal periods where women lose up to 40 mL of blood per cycle, some women lose as much as 80 mL (more than a quarter of a cup) in at least one cycle throughout their life. Scientists think they might have found the answer as to why this happens, and they are blaming it on a non-hormonal protein. A new small study suggests that low levels of a specific protein known as hypoxia-inducible factor 1 (HIF1, right) might be to blame.

HIF1 is a pretty handy healing molecule. When oxygen levels drop in parts of the body, a condition known as hypoxia, HIF1 activates more than 60 genes linked to tissue regeneration, and has already been shown to play a role in repai ...

At least to some scientists it is. Scientists believe that catching a yawn is a sign of empathy, since it is more likely to occur between relatives than strangers. Plus, other social primates like chimps and bonobos do it, too. A new study suggests that women (traditionally branded the more empathetic sex) might be more susceptible to copycat yawning than men. Researchers surreptitiously analyzed more than 4000 real-world yawns on planes and trains, in restaurants, and in offices. They noted when someone yawned, and then whether a nearby acquaintance or friend did the same within a 3-minute period. Men and women spontaneously yawned with about the same frequency. But when someone else yawned first, women were more likely than men to follow ...