The second the weather transitions from the dead of winter to kind of bearable, it seems like everyone debuts their open-toed shoes, sits outside for happy hour, and makes plans to hang at the park. Granted many of us are still getting pummelled with winter weather, but the first official day of spring is next week, so you may already be pumped.
Some people refer to this anticipation as "spring fever," but it turns out the phenomenon has a less-than-sexy origin story. Way back in the 18th century, people used to get sick with scurvy around springtime, because they didn't have access to fresh fruits or vegetables all winter. People would end up deficient in vitamin C, which made their gums bleed, their joints ache, and they generally just felt unambitious. This seasonal illness was dubbed "spring disease" or "spring fever," and somehow the name stuck.
Nowadays, people use "spring fever" to describe the distraction, restlessness, and excitement that we feel at the start of spring. While there's no official medical condition or diagnosis for "spring fever," there is definitely some science to explain the way the change in season can affect your mood.
For several years, psychologists have examined the way that the seasons impact people's mental health. There's a good chance you've heard of seasonal affective disorder (SAD), which is a type of depression with a seasonal pattern, according to the American Psychological Association. For most people with SAD, symptoms tend to hit during the winter months.
On the flip side, there's evidence that some people — with SAD and without — have improved moods and increased energy levels around the springtime, says Dan Oren, MD, a psychiatrist who studies SAD and serves on the board of directors for the Center for Environmental Therapeutics. "People with SAD, by definition, do improve in springtime," he says. "They might also note their episodes are less severe during periods of bright light [and] good weather during the winter, or during a visit to a sunny climate."
It's unclear exactly why people feel better around the spring, because it's not entirely understood why SAD occurs in the first place. Some experts argue that SAD is related to delayed circadian rhythms, but others say it's more complicated than that, Dr. Oren says. Regardless, it seems that a lack of exposure to bright light (like sunlight) is a key contributor to SAD, he says. (For this reason, many doctors will prescribe light boxes for patients to use to manage symptoms.) In the springtime, days get longer on a daily basis, which means that people are exposed to more sunlight. So, spending more time in sunlight would, in theory, make people feel happier than they felt in the winter.
Besides sun exposure, there may be an evolutionary reason why people feel, you know, excited around the springtime. Most mammals time their births to coincide with the springtime, because the conditions are best for raising a baby, Dr. Oren says. While humans are extremely complex mammals, and there are myriad factors that determine when a person gets pregnant, some people may experience a surge in their sex drive in the spring, according to Scientific American. And a boost in your sex drive could potentially make you feel happier, too.
Either way, if you find yourself riled up in the next few weeks as the weather turns, just go with it. Book that outdoor yoga class, forego wearing tights, and just let your spring fever break. Because before you know it, winter will be coming.
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