Spring Equinox: How to Overcome Fatigue with Natural Supplements
The spring equinox is not a disease and has no confirmation in studies. Check what really lies behind spring fatigue and what has evidence.
April, the sun is higher, days are longer, and yet you still wake up without energy. We call this the spring equinox and treat it as something obvious. However, when researchers asked the same individuals about fatigue nine times throughout the year, they found no seasonal pattern. This does not mean your fatigue is imagined. It means that the causes are worth looking for outside the calendar: in vitamin D levels after winter, in sleep quality, sometimes in an illness you are not yet aware of. Below, we separate what can be supported by research from what is merely a promise on a supplement label.
KEY INFORMATION
• An annual study of 418 adults found no seasonal fluctuations in fatigue, although 47% of participants reported experiencing spring equinox (Blume and Vorster, Journal of Sleep Research, 2026).
• Chronic fatigue can be the first symptom of depression, thyroid disorders, anemia, diabetes, or sleep apnea.
• Vitamin D and iron have evidence in individuals with confirmed deficiency. For those with normal results, such data does not exist.
• Regular exercise and morning light have stronger support in fatigue studies than adaptogens.
Czy przesilenie wiosenne to udokumentowane zjawisko?
No. This is a colloquial term, without an equivalent in medical classifications. In a study published in the Journal of Sleep Research, 418 adults filled out questionnaires nine times throughout the year, from April 2024 to September 2025. No seasonal or monthly fluctuations in fatigue, drowsiness, or insomnia symptoms were found.
The most interesting aspect is the discrepancy between declarations and measurements. Almost half of the participants, exactly 47%, confirmed that they experience the spring equinox. Repeated surveys did not show this. The authors explain it as a cultural label: a bad week in April gets a ready name, while an identical week in October passes without comment (Blume i Vorster, Journal of Sleep Research, 2026).
One observation from this work concerns light, not the season. Fatigue in daily activities was lower on longer days, but it did not depend on whether the day was lengthening or shortening.
What remains of the colloquial concept? A few things that accumulate at the end of winter and can be measured: the lowest vitamin D level of the year, less movement, poorly slept nights. These are the points of reference, not spring itself.
When does chronic fatigue require a doctor, not a supplement?
When it lasts longer than a few weeks, does not improve after rest, and has no obvious cause. Fatigue is among the ten most common reasons for visits to primary healthcare and can be the first symptom of a disease that has not yet shown other signs.
The scale is larger than it seems. A British team compared 304,914 people who reported to their family doctor with newly developed fatigue to 423,671 individuals without such complaints. Among 237 analyzed diseases, 127 were more common in men reporting fatigue and 151 in women. The strongest associations were with depression, respiratory infections, and sleep disorders, and in women, additionally thyroid diseases (White i in., British Journal of General Practice, 2024).
Before considering fatigue as seasonal, it is worth ruling out conditions that present exactly this symptom (Latimer i in., American Family Physician, 2023):
- anemia
- hypothyroidism
- diabetes
- obturacyjny bezdech senny
- depresja
- celiakia
- side effects of medications taken regularly
No supplement will fix fatigue caused by untreated hypothyroidism or sleep apnea. However, it can delay diagnosis by months, as a short-term improvement effectively discourages a visit.
What tests are worth doing before reaching for a supplement?
The starting point is usually a complete blood count, ferritin, TSH, fasting glucose, or HbA1c, CRP, and 25(OH)D. The final scope is determined by the doctor based on the interview, as it depends on whether to add diagnostics for celiac disease, kidney diseases, or sleep apnea.
| Study | What allows checking |
|---|---|
| Morfologia z rozmazem | anemia, inflammatory state, blood diseases |
| Ferrytyna | iron deficiency with still normal hemoglobin |
| TSH | hypothyroidism and hyperthyroidism |
| Glukoza na czczo lub HbA1c | diabetes and prediabetes |
| 25(OH)D | vitamin D deficiency |
| CRP | ongoing inflammatory process |
Ferritin clearly shows why a complete blood count is not enough. The body's iron stores can be depleted before hemoglobin drops, so the complete blood count result looks normal, while symptoms persist. We have noticed that this is the most common reason why readers tell us that "the tests came back good," yet they still lack energy.
Sleep is a separate issue. If you snore, wake up with a headache, and fall asleep during the day despite eight hours in bed, no blood test will detect this. Here, diagnostics for sleep apnea are needed.
Does vitamin D improve energy after winter?
In individuals with deficiency, studies show improvement. Polish guidelines from 2023 consider a 25(OH)D level below 20 ng/ml as deficiency, 20-30 ng/ml as suboptimal, and 30-50 ng/ml as optimal. For individuals within the normal range, there is simply no data on energy improvement after supplementation.
The closest answer to this question comes from a study by the Nowak team. It involved 120 participants with an average age of 29 who reported fatigue and had a 25(OH)D level below 20 µg/l. After a single dose of cholecalciferol, 72% of participants felt improvement compared to 50% in the placebo group, and the decrease in fatigue score was greater than after placebo (Nowak i in., Medicine, 2016). However, this entire effect pertains to the group with confirmed deficiency and does not transfer to a person with a result of 35 ng/ml.
Polish recommendations also describe who and how often should measure 25(OH)D and how to proceed in at-risk groups (Płudowski et al., Nutrients, 2023). We do not provide specific doses here. Recommendations differentiate them based on body weight, age, and accompanying diseases, so a sensible decision is made after seeing the result, not after reading an article.
Who does iron supplementation actually help?
Menstruating women with low ferritin levels, where other causes of fatigue have been ruled out. Outside of this group, there is no convincing data, and excess iron is harmful. Without a ferritin result, supplementation is like shooting in the dark.
A reference point is a study from CMAJ. It involved 198 women aged 18-53, all with unexplained fatigue, ferritin below 50 µg/l, and normal hemoglobin. For 12 weeks, they received either iron or placebo. The fatigue score dropped by 47.7% in the iron group and by 28.8% after placebo (Vaucher et al., CMAJ, 2012). Quality of life, severity of depression, and anxiety did not change in either group, which is worth remembering, as it shows the limits of this effect.
A newer study from 2026 included 164 women of childbearing age, also non-anemic and with low ferritin levels. After two months, the fatigue score decreased, and ferritin increased (Sultana i in., JPMA, 2026). Both studies share one thing: the participants were chosen precisely because they had a deficiency. This is not evidence of iron's effect on anyone else.
Co wiadomo o magnezie i witaminach z grupy B?
Less than what the packaging suggests. Research on magnesium and B vitamins most often involves individuals with deficiencies or specific issues, such as poor sleep quality. Where participants were healthy and well-nourished, the effects are small or measured by something other than daily fatigue.
The closest to the topic is a study from 2025 involving 155 adults who self-reported poor sleep quality. Magnesium biglycinate reduced insomnia scores more than placebo, but the effect size was 0.2 (Schuster i in., Nature and Science of Sleep, 2025). Additional analysis suggests greater improvement in individuals with lower magnesium intake in their diet, again in the group with a probable deficiency.
The situation is similar with B vitamins. A four-week supplementation of a B complex in 32 healthy individuals extended the time to exhaustion (Lee i in., International Journal of Medical Sciences, 2023). This is the result of a fitness test from a small group, not an answer to the question of morning sleepiness. Deficiencies in B12 and folates can be a real issue for vegans and older adults, but then we are talking about treating a deficiency.
Do adaptogens reduce fatigue?
The evidence is weaker than the advertisements suggest. They come from small groups with very different profiles, and the subjects almost never had a diagnosed chronic fatigue syndrome. Below is a summary of what has actually been tested.
| Plant | Osoby i czas | Outcome |
|---|---|---|
| Ashwagandha (Witholytin) | 120 adults aged 40-75 with overweight, 12 weeks | fatigue scores lower than after placebo, primary endpoint no difference |
| Ashwagandha (Shoden) | 60 healthy stressed adults, 60 days | anxiety and cortisol were measured, fatigue was not assessed |
| Rhodiola rosea | 48 nursing students on shifts, 42 days | placebo performed better on the vitality scale |
| Ginseng | meta-analysis of 19 randomized studies | no difference in overall analysis, small effect in subgroups |
Lopresti's 2019 study is often presented as evidence that ashwagandha alleviates fatigue. This was not the case: it measured anxiety levels and cortisol concentrations in 60 stressed but healthy individuals (Lopresti i in., Medicine, 2019). Fatigue was only assessed in a study from 2023 (Smith i in., Journal of Psychopharmacology, 2023).
Rhodiola rosea performed worse than placebo in a reliable trial (Punja i in., PLOS ONE, 2014), and a meta-analysis of 19 studies on ginseng showed no difference compared to control groups (Li i in., Journal of Integrative and Complementary Medicine, 2023).
What works besides supplements: movement, light, or coffee?
Movement and light have better support in fatigue research than most supplements. Caffeine works acutely, but you pay for it with a rebound after withdrawal. This is the cheapest part of the plan and usually the most overlooked.
A six-week aerobic program involved 36 sedentary, healthy young adults who reported persistent fatigue. They exercised three times a week, and improvements were noted in energy and fatigue scales (Puetz i in., Psychotherapy and Psychosomatics, 2008). Moderate intensity effort was sufficient. The group was small, so consider this a suggestion, not a certainty.
The situation with light is more interesting. In the aforementioned annual study, fatigue in daily activities decreased with longer days. A morning walk is therefore a reasonable idea, although it has not been tested in a randomized trial on healthy individuals.
Caffeine works, but only briefly. A review of 57 experimental studies confirmed that after withdrawal, fatigue, decreased energy, and drowsiness appear, and headaches occurred in half of the subjects. Symptoms begin 12-24 hours after the last dose and last from 2 to 9 days (Juliano i Griffiths, Psychopharmacology, 2004). Increasing the number of coffees does not cure fatigue, it only sustains the cycle.
Frequently Asked Questions
Czy przesilenie wiosenne to choroba?
No. This is a colloquial term, without an equivalent in medical classifications. An annual study of 418 adults, published in the Journal of Sleep Research in 2026, found no seasonal fluctuations in fatigue, drowsiness, or insomnia symptoms. The authors describe the equinox as a cultural label, not a seasonal syndrome.
What tests should be done if fatigue persists?
The starting point is usually a blood count, ferritin, TSH, fasting glucose, or glycated hemoglobin, CRP, and 25(OH)D. The range is determined by the doctor based on the interview. If you snore and fall asleep during the day, additional diagnostics for sleep apnea may be needed.
Is it worth taking vitamin D without testing its level?
Studies on fatigue included individuals with confirmed deficiency, not those with normal results. Polish guidelines from 2023 consider a 25(OH)D level below 20 ng/ml as deficiency, and 30-50 ng/ml as optimal. Measuring 25(OH)D answers this question more cheaply than guessing.
Does magnesium help with fatigue?
The data is modest. In a 2025 study of 155 adults with poor sleep, magnesium biglycinate reduced insomnia scores more than placebo, but the effect size was 0.2, which is small. Greater improvement was noted in individuals with low magnesium intake in their diet.
Czy ashwagandha dodaje energii?
In a twelve-week study of 120 overweight adults reporting stress and fatigue, fatigue scores dropped more than after placebo. The primary endpoint, perceived stress, did not differ from placebo. None of these individuals had a diagnosed chronic fatigue syndrome.
How long does fatigue last after quitting coffee?
A review of 57 experimental studies found that withdrawal symptoms begin 12-24 hours after the last dose, peak between 20 and 51 hours, and last from 2 to 9 days. These include fatigue, decreased energy, drowsiness, and headache.
We wrote about building reserves before the infection season in the post supplements for autumn and immunity. If studies show a specific deficiency to be supplemented, you can find products in the category supplements.
This article is for informational and educational purposes and does not constitute medical advice. Before starting supplementation, consult your doctor, especially if you are taking medications regularly, are pregnant or breastfeeding, or have a chronic illness.
Author: Michał Waluk · Opublikowano: 2026-06-22 · Aktualizacja: 2026-08-08
