Low levels of folate and Vitamin B12 are associated with the rise in chronic fatigue cases in modern populations.
See the scientific wording
Deficiencies in folate (Vitamin B9) and Vitamin B12 are systematically linked to the modern epidemic of chronic fatigue.
Very strong evidence
Mixed evidence3 high-quality studies support this claim.
What the research says
3 studies reviewedSupporting (3)
Randomized Controlled TrialHuman2026
Giving people B vitamins (including B12) made their fatigue better in a study of people with a gut disease, which suggests that low B vitamins might be one reason people feel super tired all the time.
Randomized Controlled TrialHuman
This study found that giving people with schizophrenia extra B12 and folate made them feel less tired and less emotionally flat—symptoms very similar to chronic fatigue. This suggests low levels of these vitamins might cause fatigue-like feelings, which supports the idea that modern vitamin deficiencies could be contributing to the rise in chronic fatigue.
Association of Vitamin B12 Deficiency with Fatigue and Depression after Lacunar Stroke
Cross-Sectional StudyHuman2012
This study found that stroke patients with low B12 levels felt much more tired than those with normal levels, suggesting that low B12 might make people feel fatigued. While it doesn't prove this causes the modern rise in fatigue, it shows a clear connection.
Contradicting (0)
No contradicting studies found yet
That doesn't mean it's settled — it just means no study has tested the opposite.
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Score breakdown, mechanism chain, raw evidence, ideal studies needed & 3 supporting studies
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