The importance of optimizing COVID-19 vaccine efficacy by ensuring nutritional adequacy was raised early this year, and scientists diligently work on uncovering vitamin supplements’ potential in this regard.
A recently published letter to the editor by an international team from Italy and Bulgaria in European Review for Medical and Pharmacological Sciences suggests that vitamin D supplementation is a potential adjuvant for COVID-19 vaccines.
The letter states increasing vitamin D levels could improve the vaccine’s efficacy, especially in people with inadequate nutritional status.
Velikova, Fabri, and Infante reviewed the existing literature regarding the vitamin D insufficiency impact on the COVID-19 infection and its possible effect on the vaccination outcomes as well.
The published studies indicate that low vitamin D levels may favor worsening of the infection and the development of hyperinflammation, also called “cytokine storm.”
The latter is assumed as one of the most severe complications of COVID-19, and it’s linked to higher morbidity and mortality.
Initial interventional studies assessing the efficacy of vitamin D supplementation on COVID-19 severity and death were promising.
Since we rely on vaccination to end the pandemic, it’s worth assessing the possible positive effects of vitamin D on COVID-19 vaccines, especially in people at higher risk for a poor immune response after vaccination.
The more sensitive group includes the elderly, malnourished and immunodeficient individuals, immunosuppressive drugs users, etc.
Additionally, these people usually have other nutritional deficiencies, lacking minerals (zinc, selenium, iron, and copper), vitamins (A, B6, B9, B12, C, D, and E), proteins, etc.
And several studies demonstrate that inadequate host nutritional status results in a weak immune response and inadequate protection against the infectious agents.
Moreover, vitamin D deficiency is also regarded as a “global pandemic,” as over one billion individuals across all age groups have insufficient levels of this nutrient.
And this vitamin could enhance immune responses after vaccination or infection by providing stimulation of the immune cells.
Therefore, the authors also proposed that nutritional supplementation with immunity-enhancing minerals and vitamins, especially vitamin D, should be offered to all individuals mentioned above.
They also pointed out that their deficiencies should be addressed by supplementation for a certain period both before and after the COVID-19 vaccine.
Naturally, further studies are needed to confirm the claims. But at the moment, given the generally low cost of multivitamin supplements, supplementation with vitamin D could serve as a cost-effective investment for ensuring an adequate vaccine response, particularly in those with weakened immune systems.
