Spring Fatigue: Is It Real? What a Study of 418 Adults Found
The days get longer, the sun is back – and you feel more tired than in winter. Spring fatigue seems to belong to spring as much as pollen counts. But is it real?
This guide shows what a recent study found, which explanations are discussed – and when tiredness should be checked by a doctor.
Spring fatigue: is it real? What the research shows
For a long time there were hardly any studies. In 2026, Swiss researchers measured it systematically for the first time:
Seasonal variation in fatigue and sleep (Blume & Vorster, 2026)1
- Perception: 47% said at the start that they know or experience spring fatigue.
- Measurement: Over the year, answers showed no seasonal or monthly fluctuations in fatigue, sleepiness, insomnia symptoms or sleep quality.
- The authors’ interpretation: spring fatigue appears to be a culturally shaped phenomenon rather than a seasonal syndrome. People who know the term tend to label spring exhaustion that way.
- Limitations: self-reported online questionnaires, mostly women. The study does not say that nobody feels tired in spring.
That does not mean your tiredness is imagined. It means a typical spring pattern could not be shown in the data. If you feel tired, keep other possible causes in view too.
Which explanations are discussed – and what is proven?
Open what interests you:
Hormones: serotonin and melatonin
The most often cited idea is an imbalance of serotonin and melatonin as daylight increases. One piece is documented: in 101 healthy men, brain serotonin turnover was lowest in winter and rose with the duration of bright sunshine.2 That concerns mood and serotonin, not tiredness, and only men were studied.
Sleep patterns and the clock change
Lighter mornings and longer evenings can shift sleep. Whether that leads to more tiredness in spring was not shown by the Blume and Vorster study: participants sometimes slept less in summer without feeling more exhausted.1
Nutrients after winter
A common guess is that some nutrients run low after winter, such as vitamin D. We found no evidence for this specifically for spring fatigue. Whether you have a deficiency can only be clarified by a doctor. If tiredness is your main theme, our article Always Tired? What a B12 Deficiency Could Mean covers one cause worth knowing.
Expectation and attention
The authors suspect that the well-known term “spring fatigue” steers perception: if you know it, you tend to read spring exhaustion that way.1
Normal or get it checked? How to sort your tiredness
An orientation, not a substitute for medical advice:
Usually temporary
A few weeks of sluggishness during weather and rhythm changes that eases on its own.
Worth watching
Tiredness despite enough sleep over several weeks. A diary helps you spot patterns.
Get it checked
Persistent exhaustion, low mood, loss of drive or other symptoms.
What you can note down:
- How long and how well you sleep
- When during the day tiredness hits
- Daylight and movement
- Mood and other symptoms
Spring fatigue FAQ
Is spring fatigue real?
Not as a medical diagnosis. In a study of 418 adults surveyed repeatedly over about a year, there were no seasonal swings in fatigue, sleepiness, insomnia symptoms or sleep quality – even though 47% said they knew spring fatigue. The feeling can still be real.
Why do I feel tired in spring?
Several explanations are discussed, such as changes in daylight and sleep patterns, or expectation effects because the term is so well known. None is firmly proven. Persistent tiredness can also have entirely different causes.
How long does spring fatigue last?
Guides often say two to four weeks. That is not proven, because it cannot be measured as a condition of its own.
What can I do about tiredness in spring?
The study’s lead author recommends getting as much daylight as possible, staying physically active and getting enough sleep. These are general everyday tips, not a treatment.
Do supplements help with spring fatigue?
We make no statement about that. Supplements are not a substitute for a balanced diet or sleep, and they do not tell you where your tiredness comes from.
When should I get tiredness checked by a doctor?
If it lasts for weeks, gets worse or comes with low mood, loss of drive or other symptoms. A doctor can then check whether for example iron deficiency, thyroid problems, low vitamin D or sleep disorders play a role. This is general orientation.
The bottom line: take tiredness seriously, question the label
Spring fatigue is not a recognised medical condition, and a recent study could not show a seasonal tiredness pattern. The feeling can still be real. If it lingers, look for the causes rather than simply blaming spring.
- Blume C, Vorster A (2026): No Evidence for Seasonal Variations in Fatigue, Sleepiness and Insomnia Symptoms: Spring Fatigue Is a Cultural Phenomenon Rather Than a Seasonal Syndrome. Journal of Sleep Research, e70319. doi.org/10.1111/jsr.70319
- Lambert GW, Reid C, Kaye DM, Jennings GL, Esler MD (2002): Effect of sunlight and season on serotonin turnover in the brain. The Lancet 360(9348):1840–1842. doi.org/10.1016/s0140-6736(02)11737-5
This article does not replace medical advice, diagnosis or treatment. For persistent tiredness, please speak to your doctor.
