What is Spring Fever?

Body Chemistry and Seasonal Biology

Feb 21, 2009 Mary Desaulniers

Spring Fever is a physiological and psychological shift in the body's response to changing seasons.

It comes with telling signs: restlessness, intense nervous excitement, high-energy spurts, loss of appetite, insomnia, a yearning to break away or a desire, as one friend puts it,” to run away with mad love.” Spring fever has appeared in love poems, stories and medical literature.

Statistically, at least half of the people who live in the northern latitudes of USA and Canada experience more intensely the symptoms of Spring fever. Longer sunny days seem to have a direct impact on people’s psychological and physiological responses to the passage of the seasons. Spring fever is not just in the head. It is caused by an adjustment in body chemistry and seasonal biology.

Spring Fever and Body Chemistry

Doctors have attributed the phenomenon of spring fever to human reaction to seasonal changes. Since the mid 1980s, scientists have validated the diagnosis of Seasonal Affective Disorder ( SAD), a depression and mood disorder that emerges during the fall and winter months. They have also perceived a noticeable departure of SAD symptoms with the coming of spring and summer. One reason is the realignment of the body’s chemistry with sunlight. Changes during spring can readjust body chemistry, specifically the internal body clock that responds to sunlight.

The circadian rhythm of the internal body clock is affected by light. The body’s secretion of melatonin, a hormone that influences sleep and energy levels, is also affected by light. During the winter, the body’s secretion of melatonin is relatively high; during spring, however, the level of melatonin decreases, which results in greater wakefulness. Serotonin levels also increase during spring which accounts for the breakaway sense of elation. Research also suggests that spring weather is linked to spikes in hypomania, when individuals experience a sense of inflated grandiosity, uninhibited pursuit of "the chase," and a significantly reduced need for sleep.

Spring Fever and Seasonal Biology

Is love in the air during spring? Is there a biological basis for this as well? Studies show that sexual behavior in animals follows a seasonal pattern. Birth spikes in field mice, hares and deer are more pronounced in areas farthest from the equator because changes in seasons are more defined in these areas. Seasonal cycles in human rates of conception occur as well. Historically, there have been more births in spring, which means that babies are conceived most often during the summer months, when the luteinizing hormone (that spurs the production of testosterone in men and triggers ovulation in women) is at its peak.

However, studies also show that there are more unplanned pregnancies conceived in spring than at any other time of the year, a situation that can be partially explained by peaking sperm counts during the spring months.

There is a darker side to spring fever, however, which usually does not get much attention. While some people respond to spring with a burst of enthusiasm, others seem mired in dashed expectations and doldrums. Hospitals report that suicides and depression peak during the spring months.

The copyright of the article What is Spring Fever? in General Medicine is owned by Mary Desaulniers. Permission to republish What is Spring Fever? in print or online must be granted by the author in writing.

Spring Fever