Heap, L C, Peters, T J, Wessely, S · Journal of the Royal Society of Medicine · 1999 · DOI
This study tested whether people with ME/CFS have lower levels of three B vitamins (B6, B2, and B1) compared to healthy people. Researchers measured how well these vitamins work in red blood cells from 12 ME/CFS patients and 18 healthy controls. They found that all three B vitamins appeared to be functioning less effectively in ME/CFS patients, suggesting a possible vitamin deficiency that might contribute to symptoms.
B vitamins are essential for energy metabolism and cellular function, both known to be compromised in ME/CFS. If ME/CFS patients truly have reduced functional B vitamin status, this could explain some fatigue symptoms and might inform treatment approaches, though this finding requires replication before clinical recommendations can be made.
This study does not prove that B vitamin deficiency causes ME/CFS or that B vitamin supplementation will improve symptoms. The correlation observed does not establish causation, and the small sample and cross-sectional design prevent any definitive conclusions about whether supplementation would help individual patients.
About the PEM badge: “PEM required” means post-exertional malaise was an explicit required diagnostic criterion for participant inclusion in this study — not that PEM was studied, observed, or discussed. Studies using criteria that do not require PEM (e.g. Fukuda, Oxford) are tagged “PEM not required”. How the atlas works →
The first block is for the primary paper and is the citation you should use in research work. The atlas-snapshot line only applies if you are specifically referring to this atlas’s reading of the paper on the date shown.
Primary citation
Heap, L C, Peters, T J, & Wessely, S (1999). Vitamin B status in patients with chronic fatigue syndrome.. Journal of the Royal Society of Medicine. https://doi.org/10.1177/014107689909200405
BibTeX
@article{mecfsatlas-heap-1999-vitamin-status,
author = {Heap, L C and Peters, T J and Wessely, S},
title = {Vitamin B status in patients with chronic fatigue syndrome.},
journal = {Journal of the Royal Society of Medicine},
year = {1999},
doi = {10.1177/014107689909200405},
note = {PubMed: 10450194},
url = {https://www.mecfsatlas.com/evidence/heap-1999-vitamin-status},
}Atlas snapshot reference
ME/CFS Atlas. Generator v1 / Scanner v1.4 / policy v0.1. Accessed 2026-05-25. https://www.mecfsatlas.com/evidence/heap-1999-vitamin-status
Contribute
Private, reviewed by a human. Not a public comment thread.