Research involving over 17,000 people found that more than half had insufficient vitamin D levels, with the highest rates among Black communities.
Date: 30 November 2025
More than half of South East London residents had vitamin D deficiency or insufficiency at the onset of the COVID-19 pandemic, according to new research from London Metropolitan University and King's College London.
The study, led by Professor Laurence Harbige and Dr Agata Sobczynska-Malefora of St Thomas' Hospital, analysed data from over 17,000 people and found deficient or insufficient vitamin D levels in 61% of Black, 55% of Asian, and 50% of White individuals.
Published last month in the international journal Nutrients, the retrospective study also revealed differences in vitamin D levels across age, body mass index (BMI), and sex. Black individuals, males, and those who were overweight or obese showed the highest rates of deficiency or insufficiency. The findings mirror global research showing a link between low vitamin D levels and being overweight.
Vitamin D deficiency was also found to be highly prevalent among individuals who tested positive for SARS-CoV-2. This was particularly noticeable among Black individuals with existing low vitamin D levels. Importantly, many published studies have highlighted the potential beneficial role of vitamin D in improving COVID-19 outcomes such as survival and lower disease severity as well as the antibody response to SARS-CoV-2 vaccines.
The research team also found evidence of increased inflammation among SARS-CoV-2 positive individuals who had low vitamin D levels — a possible detrimental factor influencing how the body responds to viral respiratory infections such as SARS-CoV-2.
Professor Harbige explained that understanding the prevalence and effects of vitamin D deficiency in a pre-COVID-19 vaccine population offers valuable insights for future pandemic preparedness. "Identifying modifiable risk factors such as vitamin D deficiency is key to protecting high-risk groups and improving public health resilience," he said. The researchers hope their findings will contribute to shaping public health strategies in the UK and beyond.
