There aren’t many of us who welcome dark days and cold weather – but if you have multiple sclerosis, you may be one of them. Although most people complain about getting sick in the autumn and winter months, you may actually find your MS symptoms improve at this time of year.
Scientists have long noticed a link between seasonal changes and MS symptoms . Several theories have been put forward as to why this might be, from fluctuations in Vitamin D levels to UV incidence and upper respiratory tract infections. Researchers at the Ann Romney Center for Neurologic Diseases at Brigham and Women’s Hospital in the US, together with scientists from other research institutes, decided to investigate further.
After monitoring 139 people with relapsing–remitting MS for a year, the team discovered relapse rates were indeed lower during autumn and winter than other times of the year – by almost a third (32%), in fact. They also found this appeared to correlate with subjects’ levels of melatonin , the hormone that helps regulate sleep .
We know melatonin levels are higher during the shorter days of autumn and winter when there’s less daylight (which is one reason you feel sleepier and find it harder to get out of bed). Could this also be the reason why MS symptoms can often appear to decrease during these months?
When researchers investigated more closely, using mouse and human cells in the lab, they found melatonin triggered the production of regulatory T cells (immune cells that keep myelin-munching killer T cells in check), and also blocked the production of new killer T cells. In other words, melatonin appears to dampen the immune system and stop it from attacking myelin (the protective “sheath” that protects nerves and becomes eroded due to MS).
Although these results are exciting, researchers are keen to point out this doesn’t mean anyone with MS should start popping melatonin pills. For starters, the pills cause extreme drowsiness – and fatigue is something many people with MS already struggle with. There’s also no evidence melatonin is effective in treating MS. With more research, however, scientists may be able to uncover some more clues to help develop new treatment approaches for MS, or at the very least ease symptoms.
In the meantime, we have one less reason to curse shorter days and dark mornings. Not that it will make it any easier to get out of bed, of course.