NEW YORK, Feb 8 ― Surprising as it may seem, science has now discovered a link between body temperature and depression. The work of a team of US researchers suggests that people suffering from this mental disorder have a higher body temperature, albeit without being able to establish whether this could be a cause or a consequence of depression.

Depression, loss of pleasure, sleep disorders, reduced energy, loss of self-confidence, low self-esteem and hopelessness about the future are all symptoms that could be a sign of depression, according to France's public health insurance organisation. These signs are further highlighted by the World Health Organisation (WHO), which also mentions excessive feelings of guilt and suicidal thoughts, and estimates that 5 per cent of adults worldwide suffer from depression. But another sign, this time a physical one, could alert people to a potential state of depression: their body temperature.

These are the findings of a team of researchers at the University of California, San Francisco, who set out to determine whether there was a link between body temperature and depression. The scientists analysed data from 20,880 participants from 106 countries, with an average age of 46.9. They wore body temperature monitors, and were asked to report their temperature and potential symptoms of depression on a daily basis, over a period of seven months.

A higher temperature

Published in the journal, Scientific Reports, the research suggests that people suffering from depression have a higher body temperature. In detail, the researchers report that as depression-related symptoms worsen, participants' body temperature increases. "The body temperature data also showed a trend toward higher depression scores in people whose temperatures had less fluctuation throughout a 24-hour period, but this finding didn’t reach significance,” an accompanying news release explains.

However, the researchers were unable to determine whether the rise in body temperature was a cause or a consequence of depression. Still, this does not prevent them from advancing the hypothesis of a possible "novel depression treatment method,” consisting in lowering the body temperature of those concerned. In particular, they evoke the use of jacuzzis or saunas to achieve this by stimulating self-cooling in the body.

"Ironically, heating people up actually can lead to rebound body temperature lowering that lasts longer than simply cooling people down directly, as through an ice bath,” says the study's lead author, Ashley Mason, a professor of psychiatry and clinical psychologist, quoted in a news release. "To our knowledge, this is the largest study to date to examine the association between body temperature ― assessed using both self-report methods and wearable sensors ― and depressive symptoms in a geographically broad sample,” adds Mason. "Given the climbing rates of depression in the United States, we’re excited by the possibilities of a new avenue for treatment.” ― ETX Studio