Reviewed by:
Dr. Patricia Núñez de Aysa — Medical expert in Longevity, specialist in Rehabilitation and Traumatology without surgery.
Dr. Joel Cuesta Gascón — Medical expert in sports medicine, rehabilitation, and nutrition.
Last updated: May 2026.
In 30 seconds
- Spring asthenia is a popular concept, not an official medical diagnosis. It does not appear in international classifications such as ICD-11.
- A longitudinal study published in 2026 with over 400 adults found no consistent seasonal variations in levels of fatigue, sleepiness, or insomnia.
- The tiredness you do notice in spring has real causes: time change, seasonal allergies, stress peaks, poorer sleep… but not an "asthenia" inherent to the season.
- The solution is not a "miraculous spring anti-fatigue," but identifying what your body needs: mental clarity, immune support, better rest, or nutritional intake.
Spring asthenia: popular belief vs. evidence
Spring arrives, temperatures rise, there are more hours of daylight… and almost half the population starts complaining of the same symptom: extreme tiredness, sleepiness, lack of energy. We call it spring asthenia and take it for granted as if it were a physiological mechanism as natural as breathing.
But when we contrast that belief with current medical literature, a quite different picture emerges. Spring asthenia does not appear as an official diagnosis in the ICD-11 (the WHO's international classification of diseases) nor in reference internal medicine manuals. It has no defined diagnostic criteria, no standardized treatment, and no associated biological markers.
What it does have is an enormous cultural presence. And that, in itself, is also relevant.
What science says: the 2026 longitudinal study
A study published in 2026 evaluated over 400 adults for a full year, systematically measuring levels of fatigue, sleepiness, sleep quality, and mood in each season. Its conclusions were revealing:
- No consistent seasonal variations in fatigue levels were found.
- Subjective complaints of tiredness did not correlate with a fixed seasonal pattern.
- The factors that did explain differences were individual: stress, sleep, diet, exercise, nutritional deficiencies, and specific life events.
Researchers' conclusion: spring asthenia functions more as a cultural and psychological phenomenon than as a real medical syndrome. We expect to feel tired in spring because tradition dictates it, and that expectation bias influences how we interpret sensations that are actually non-specific and multifactorial.
So, why do I actually feel more tired in spring?
The fact that spring asthenia is not an official diagnosis does not mean your tiredness is imaginary. It is real. But the causes are usually different:
1. Time change
The shift to daylight saving time means losing an hour of sleep. The adaptation of the circadian rhythm can take one to two weeks, manifesting as daytime sleepiness, poorer concentration, and worse mood. It's not asthenia: it's circadian misalignment.
2. Seasonal allergies
Pollen and other typical spring allergens trigger inflammation of the mucous membranes. This affects sleep quality (nighttime congestion), generates fatigue, and lowers performance. In atopic individuals, much of "spring tiredness" is poorly controlled allergy.
3. Light and temperature changes
More hours of daylight mean more social activity, more exposure, more stimuli. The body needs to readjust its rhythm, and that consumes energy for a few weeks.
4. Peaks of stress and work overload
It coincides with demanding academic and work periods of the year (Q1 closings, exams, summer organization). We attribute it to "spring," but it's accumulated stress.
5. Subclinical nutritional deficiencies
Vitamin D at the end of winter, magnesium in stressed individuals, iron in women with heavy menstruation… They can manifest at any time of the year, but sometimes coincide with spring and are attributed to the season.
6. Poorer sleep due to temperatures
The first warm nights alter nighttime thermoregulation. Without an adequate thermostat, the body enters deep sleep less effectively, leading to the feeling of "sleeping but not resting."
Quick table: what's behind your "spring asthenia"
| What you feel | Most probable cause | Where to start |
|---|---|---|
| Daytime sleepiness, mental slowness | Time change, poorer sleep | Sleep hygiene, morning light |
| Tiredness + sneezing, itchy eyes | Seasonal allergy | Allergy assessment |
| Lack of spark, low focus | B12/B6 deficiency, mental overload | B-group intake + habit review |
| Tiredness + frequent infections | Lowered defenses | Immune support |
| Cramps, poor sleep, irritability | Magnesium deficiency | Magnesium bisglycinate |
| Deep, emotional, persistent tiredness | Other medical causes | Blood tests + medical assessment |
How to address fatigue based on evidence (without falling for miracle cures)
Medical guidelines do not recommend a specific "treatment" for seasonal fatigue because, simply, it does not exist as an entity. What they do recommend is identifying the specific cause and acting on it. These are the most evidence-based approaches:
1. Take care of the basics: sleep, light, and movement
Before any supplement, the three pillars with the most impact on your energy are:
- Sleep: 7-9 hours, regular schedule, cool and dark bedroom.
- Morning natural light: 20-30 minutes outdoors in the first hours of the day regulate your cortisol and melatonin better than any supplement.
- Moderate physical activity: 30-45 minutes a day, preferably with natural light.
2. Support your nervous system when it needs it
If the tiredness is mainly cognitive (lack of spark, difficulty concentrating, feeling of brain fog), the goal is to support the normal functioning of the nervous system. Nutrients with recognized health claims by the EFSA in this area are:
- Vitamin B12 and B6: contribute to the reduction of tiredness and fatigue, to normal energy metabolism, and to normal psychological function.
- Vitamin B1 (thiamine): contributes to the normal functioning of the nervous system.
In cognitive performance formulas, these vitamins are often combined with amino acids such as L-tyrosine and botanical extracts such as Panax Ginseng, Ginkgo biloba, or green tea (which provides L-theanine and natural caffeine). This is the approach we use in Voltage: sustained energy without jitters, mental focus, and physical performance, formulated by doctors.
3. Boost your defenses during seasonal changes
When tiredness is associated with increased susceptibility to infections or a feeling of cellular wear and tear, what the body needs is immune support. Nutrients with evidence:
- Vitamin C, vitamin D3, zinc, and selenium: contribute to the normal functioning of the immune system.
- Vitamin A: contributes to the maintenance of mucous membranes, the first defensive barrier.
- Zinc, selenium, and vitamin C: contribute to the protection of cells from oxidative damage.
- Vitamin B9 (folic acid): contributes to the reduction of tiredness and fatigue.
Advanced formulas also include Coenzyme Q10 and N-acetyl-cysteine (NAC) to support cellular energy and antioxidant protection. This is how our Immune is formulated: defenses, cellular energy, and protection against oxidative stress, in a single capsule.
4. Review your nutritional foundation
If you've been tired for months, don't assume it's "spring." A basic blood test (CBC, ferritin, vitamin D, B12, thyroid profile) rules out the most common causes of real fatigue. From there, supplementing makes much more sense and has a much greater effect.
When to consult a professional
Occasional tiredness associated with a change of season should not worry you. But a medical evaluation is advisable if:
- Tiredness lasts more than 4-6 weeks without improving.
- It limits you at work, in sports, or in your daily life.
- It is accompanied by weight loss, fever, night sweats, or swollen lymph nodes.
- You notice persistent low mood, apathy, or loss of interest.
- You have poorly controlled seasonal allergies that affect your sleep.
- You suspect a significant nutritional deficiency or take chronic medication.
At tres60, we offer free medical consultation with our specialists if you want personalized guidance.
Conclusion
Spring asthenia is more of a cultural myth than a medical condition. We expect to feel tired in spring because tradition dictates it, and that bias influences how we interpret tiredness that, in reality, is non-specific and multifactorial.
That doesn't mean your fatigue isn't real. It means it's not solved with a "miraculous spring anti-fatigue," but by understanding what your body specifically needs: rest, nervous support, immune reinforcement, or nutritional intake.
If you need support for your nervous system and cognitive performance, discover Voltage. If you are looking to strengthen your defenses and cellular energy, discover Immune. And if you want to know what best suits your case, write to us on WhatsApp: our doctors will answer you free of charge.
Frequently asked questions about spring asthenia
Does spring asthenia exist as a disease?
No. It is not recognized as an official medical diagnosis in ICD-11 or in reference manuals. It is a popular concept without defined medical criteria.
Why does almost everyone say they notice it?
Due to a combination of real factors (time change, allergies, stress) and cultural expectation. We expect to feel tired in spring, and that bias influences how we interpret our state.
How long does spring asthenia last?
It depends on the actual cause. Poor adaptation to time change usually lasts 1-2 weeks. A seasonal allergy, as long as the pollen lasts. A nutritional deficiency, until corrected.
What vitamins to take for spring asthenia?
There is no standard "cocktail." It depends on the profile: if it's cognitive tiredness, B-group vitamins (B1, B6, B12) and amino acids like L-tyrosine; if it's wear and tear and lowered defenses, vitamin C, D3, zinc, selenium, and antioxidants. Before supplementing, a basic blood test is advisable.
Can spring asthenia be cured with supplements?
It is not "cured" because it is not a disease. But the right nutrients can help you regain energy, rest, and mental clarity when there are real deficiencies or wear and tear behind it.
How to distinguish spring asthenia from something more serious?
If tiredness lasts more than 4-6 weeks, is accompanied by weight loss, fever, persistent low mood, or limits your daily life, it's not "spring": it's time for a medical evaluation.
Can pollen allergy cause tiredness?
Yes. Poorly controlled allergies disrupt sleep (nighttime congestion), generate systemic inflammation, and cause fatigue. A good part of "spring tiredness" in atopic individuals is allergy.
Bibliographical references
- Choi DW, Chun SY, Lee SA, Han KT, Park EC. Association between Sleep Duration and Perceived Stress: Salaried Worker in Circumstances of High Workload. Int J Environ Res Public Health. 2018;15(4):796.
- Yetish G, Kaplan H, Gurven M, et al. Natural sleep and its seasonal variations in three pre-industrial societies. Curr Biol. 2015;25(21):2862-2868.
- Mattingly SM, Grover T, Martinez GJ, et al. The effects of seasons and weather on sleep patterns measured through longitudinal multimodal sensing. NPJ Digit Med. 2021;4(1):76.
- Roenneberg T, Wirz-Justice A, Merrow M. Life between clocks: daily temporal patterns of human chronotypes. J Biol Rhythms. 2003;18(1):80-90.
- EFSA Panel on Dietetic Products, Nutrition and Allergies. Scientific opinions on the substantiation of health claims related to vitamins B1, B6, B12, C, D, A, zinc and selenium.
- Allen LH. Micronutrients - assessment, requirements, deficiencies, and interventions. N Engl J Med. 2025;392(10):1006-1016.
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