Is it true that taking more vitamin D will successfully prevent COVID-19 and Influenza? No, that's not true: The study used as evidence in this video only looks at COVID patients with vitamin D deficiency in Indonesia, not at the prospect of vitamin D as a cure for COVID. Furthermore, the study doesn't mention the possibility of curing Influenza anywhere in their research.
The claim appeared on TikTok (archived here) on June 5, 2023. The video opens with an Indonesian study that links Vitamin D deficiency to COVID risks (translated from Japanese into English by Lead Stories staff):
People with more than 30ng/ml of Vitamin D in their bloodstreams never had COVID or experienced any severe risks. This means that those with low Vitamin D are more likely to catch COVID and experience severe symptoms. The easier it is to experience severe risks, then the easier it is to die from COVID.
Toward the end of the video, the user claims that taking vitamin D supplements would also help fight influenza:
Because Vitamin D is helpful in combatting COVID-19, it can also be used to cure Influenza.
This is what the post looked like on TikTok at the time of writing:
(Source: TikTok screenshot taken on Tue Jun 27 01:33:11 2023 UTC)
The study cited in the video exists, but it leaves out crucial context. For one, the randomized trials only consisted of COVID patients in Indonesia who already had vitamin D deficiency. Although the study concludes that vitamin D might be helpful in the treatment process of curing COVID patients, the study makes it clear that this is especially the case for patients who are already suffering from vitamin D deficiency.
Previous studies showed the plausibility of vitamin D prophylaxis and therapy for COVID-19, particularly in settings where hypovitaminosis D is frequent.
There are no mentions of using vitamin D as a cure for Influenza in the study. Another study from 2022 examines the potential protective effects of vitamin D supplementation and influenza, but finds the results obtained inconclusive. Therefore, there is no concrete evidence that vitamin D can fully combat Influenza.
