It is well established that people in stable relationships tend to have better mental and physical health than singletons. Now, scientists have discovered a possible explanation for this: it seems that sharing a bed promotes good sleep. Humans sleep in cycles, shifting between rapid-eye-movement (REM) sleep – during which vivid dreams occur – and non-REM periods.

Though all sleep is important, uninterrupted REM sleep is thought to be particularly beneficial to both mind and body. For a study at the Centre for Integrative Psychiatry in Kiel, Germany, 12 heterosexual couples spent four nights in a sleep lab, two of them with their partners and two alone. The researchers observed that on the nights when participants slept with their partner, they experienced around 10% more REM sleep, even though they thrashed around more. The authors of the study suspect that physical proximity to a loved one promotes certain sleep-boosting hormones, though more research is needed to establish this. They also note that their findings might have been different had any of the couples been heavy snorers. “That could certainly worsen the sleep of a partner, no doubt about it,”. (Henning Drews,The Times. and The Week)

My take: The conclusions might well be correct, but I am a bit turned off by the fact that only 12 couples were subject to this research.  How can one apply the results to the population in general, using such a tiny sample?  I note that the results of this research are not carried in the New Scientist, for instance.