Japanese scientists have linked chronic fatigue to a deficiency of B vitamins

Japanese scientists from Osaka Metropolitan University, led by Professor Hiroaki Kanouchi, have discovered an unexpected link between a deficiency of water-soluble vitamins and the development of chronic fatigue syndrome.

The results of the study were published in the journal Medical Xpress.

The scientists hypothesized that a deficiency of folic acid (B9) and vitamin B12 directly affects a person's overall well-being. The focus of attention was homocysteine — a biomarker whose concentration in the blood rises when these substances are lacking. Approximately 600 healthy Japanese residents participated in the experiment: they underwent blood tests, and their levels of motivation and fatigue were assessed using specialized scales.

The data obtained showed that participants with elevated homocysteine levels consistently had deficiencies in vitamins B12 and B9 — regardless of sex. However, fatigue manifested differently in men and women. In men, high biomarker values were associated with physical exhaustion, whereas in women, nutrient deficiency primarily led to decreased motivation.

"The discovered link between vitamin B12, folic acid, and fatigue in healthy people appears to be the first such scientific observation," Kanouchi stated.

The head of the research group explained that until now, in medical practice, homocysteine levels had been assessed exclusively in the context of risks for cardiovascular diseases, dementia, and fractures. The new data, he said, suggest that fatigue and motivation indicators must also be taken into account going forward. To prevent an increase in homocysteine concentration, it is critically important to avoid deficiencies in vitamin B12 and folic acid. A balanced diet on a consistent basis, Kanouchi emphasized, plays a decisive role in this.

When analyzing the results, the researchers took into account accompanying factors affecting well-being — participants' age, sleep duration, work intensity, and dietary habits. The authors of the study specifically noted that the problem of chronic fatigue in modern society has long ceased to be a purely personal matter.