- There are reports that no clear association was found between vitamin D and fatigue.
- The evidence score is 41, and the reliability is limited.
- This is information about research findings relevant to those concerned about fatigue and to older adults.
Vitamin D is one of the nutrients involved in maintaining health in the body.
It is classified as a fat-soluble vitamin and is taken into the body through dietary intake and synthesis in the skin, among other routes.
In conclusion, there is a report that no clear association was found for how vitamin D intake affects fatigue. Research has been reported showing that no clear association was found between vitamin D and fatigue. In other words, it cannot currently be said with certainty that vitamin D is directly involved in fatigue.
This result came from a study that summarized existing findings. It examined, in patients with systemic lupus erythematosus (a disease caused by factors such as an abnormality of the immune system), how supplementing vitamin D affects fatigue. The research used a systematic review (a method that scrutinizes and summarizes multiple past studies). In other words, even when many past studies were pulled together and analyzed, a clear association was not confirmed.
There is also a report suggesting a possible involvement of vitamin D in people in a specific situation. This is a study of a small group of 58 people with fatigue who have experienced a stroke (a condition in which a blood vessel in the brain becomes blocked or ruptures). This study was conducted as a cohort study (a method that continuously observes a specific group to examine trends). In other words, the results of this study are said to show a change in symptoms.
There is also an interesting report on older adults. This is a study comparing people with and without fatigue, involving a total of 480 people. This too is based on a cohort study (a method that examines trends in a specific group). In other words, it was shown that people who feel fatigued tend to have lower vitamin D values than those who do not.
Here is information on the indicator showing the reliability of this information. The evidence score is 41, and the reliability is limited. In other words, it is still insufficient to make a judgment based on this research result alone.
In practice, results also differ from study to study. This includes reports that the direction of the research is not consistent. In other words, this shows that results vary depending on the person and the situation. In addition, because this data includes studies with a relatively small number of participants, it cannot be described as a certain finding that applies to every case.
| Study | Design | Number of Participants | Duration | Main Result |
|---|---|---|---|---|
| Lupus (2018, PMID:30157716) | Systematic review | Unknown | Unknown | No clear association was found |
| Irish medical journal (2020, PMID:32338839) | Cohort study | 58 | Unknown | A positive effect was reported |
| Nutrients (2019, PMID:31635199) | Cohort study | 480 | Unknown | A possible negative effect was reported |
The subjects include patients with SLE (systemic lupus erythematosus), 58 stroke survivors with fatigue, and a total of 480 people, including a control group, in a study of older adults with fatigue — 538 people in total.
Because the research subjects are people with specific symptoms or in specific age groups, this can serve as a reference for considering your own situation.
This research report is based on a total of 3 data sources. These were carried out through a systematic review and cohort studies.
Because these are not studies using a randomized controlled trial (RCT), causation cannot be established.
The reliability of the results obtained is also reported as limited.
What is known about the relationship between vitamin D and fatigue?
Research has been reported showing no clear association between vitamin D and fatigue. On the other hand, there are also results showing a change in symptoms in some subjects.
Is vitamin D deficiency in older adults related to fatigue?
In a cohort study of 480 people, it was shown that older adults with fatigue had lower blood vitamin D levels than those without fatigue.
Is there a report on vitamin D intake in stroke survivors?
In a cohort study of 58 people, a change in fatigue symptoms was reported following treatment. This is based on observation under specific conditions.
To summarize this report, no clear association was found between vitamin D and fatigue, and the results also differed between studies. The evidence score is 41, and the reliability is limited. With many factors intertwined, this can be described as a stage where certain evidence has not yet been fully established.
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