The association between the level of serum 25(OH) vitamin D, obesity, and underlying diseases with the risk of developing COVID‐19 infection: A case–control study of hospitalized patients in Tehran, Iran.

According to a study of 201 Iranian patients, having low serum vitamin D levels and being overweight may make you more susceptible to getting COVID-19 than people who have adequate levels of vitamin D and who are not overweight.

• Serum 25(OH) vitamin D levels were significantly lower in the group with COVID-19 compared to the matched group without COVID-19.
• There was a significant relationship between the levels of vitamin D and vulnerability to COVID-19.
• The COVID-19 groups were more likely to be overweight than controls.
• Diabetes mellitus, heart failure and hypertension, and respiratory infections were found in 20.89%, 9.65%, and 6.96% of cases, respectively. These health conditions were not different between the groups.

From Feb to April 2020, 201 people (66 males and 135 females) with COVID-19 hospitalized in Tehran, IRAN and 201 people that matched the other group by age and gender, but had not been diagnosed with COVID-19.

This study did not control for many factors that could be related like health conditions other than the ones they did consider, socioeconomic status, blood markers related to inflammation, etc. These conditions may also be related to the obesity making the obesity a secondary factor that might not be directly related to the COVID-19 diagnosis. This was a small group of individuals that may not represent the population of Iran and may not be generalizable to other countries.

The authors conclude that people with lower levels of serum vitamin D are more likely to get COVID‐19 infection. Therefore, improving an individual’s vitamin D status could have a protective role against the infection. Individuals with COVID‐19 were more likely to be overweight or obese in this study.

• The aim of this study was to determine whether an association exists between the serum vitamin D level, obesity, and underlying health conditions, as well as the vulnerability to COVID‐19 in the Iranian population and to demonstrate the general clinical and radiological picture of COVID‐19 in Iranian individuals.
• Serum 25(OH) vitamin D was measured. Serum 25(OH) vitamin D levels were considered in four categories, including deficient (<10 ng/ml), insufficient (10–30 ng/ml), sufficient (>30–100 ng/ml), and toxicity (>100 ng/ml).
• Body mass index (BMI) and underlying health conditions were obtained from chart reviews.

Abdollahi A, Kamali Sarvestani H, Rafat Z, Ghaderkhani S, Mahmoudi-Aliabadi M, Jafarzadeh B, Mehrtash V. The association between the level of serum 25(OH) vitamin D, obesity, and underlying diseases with the risk of developing COVID-19 infection: A case-control study of hospitalized patients in Tehran, Iran. J Med Virol. 2021 Apr;93(4):2359-2364. doi: 10.1002/jmv.26726. Epub 2020 Dec 29. PMID: 33314166.