|40x40px||Look up spring fever in Wiktionary, the free dictionary.|
Spring Fever is a term applied to several sets of physical and psychological symptoms associated with the arrival of spring. In general it refers to an increase in energy, vitality and particularly sexual appetite, often particularly strong in those suffering from Seasonal affective disorder (SAD) and thus experiencing lows during the winter months. It is this sense that inspires the use of the term as a title for several works of literature and entertainment. In some uses however it refers to the opposite, an unexpected loss of energy with the onset of spring.
As a translation of the German term "Frühjahrsmüdigkeit" (lit. "Spring tiredness), Spring Fever is the name for a temporary mood typically characterized by a state of low energy and weariness experienced by many people in springtime. It is not in the category of a diagnosed illness, but rather a phenomenon thought to be initiated by a change in the season.
In the northern hemisphere the symptoms usually arise from mid-March to mid-April, and depending on the person may be more or less pronounced. Weariness (despite an adequate amount of sleep), sensitivity to changes in the weather, dizziness, irritability, headaches, and sometimes aching joints and a lack of drive are the most common.
Although the causes of spring fever have not yet been fully resolved, hormone balance may play a role. According to this theory the body’s reserves of the “happiness hormone” serotonin, whose production depends on daylight, become exhausted over the winter, making it especially easy for the “sleep hormone” melatonin to have its effect. When the days become longer in springtime, the body readjusts its hormone levels, and more endorphin, testosterone and estrogen are released. This changeover puts a heavy strain on the body, which responds with a feeling of tiredness.
In addition, temperatures usually fluctuate greatly in springtime. When temperatures rise, blood pressure drops, since the blood vessels expand. Food also plays a role. In winter one tends to consume more calories, fat and carbohydrates than in summer. But during the hormone adjustment period the body requires more vitamins and proteins instead.