When? September.
For whom? University of Córdoba in Spain.
What did the scientists study? Fifty hospitalized Covid-19 patients with Covid-19 were given vitamin D. Their health outcomes were compared with 26 volunteers in a control group who did not receive the pills.
What did they find? Only one in 50 patients needed intensive care and none died. Half of the 26 patients with viruses who did not take vitamin D were subsequently admitted to intensive care and two died.
What were the limitations of the study? Small group of volunteers. Patients ’vitamin D levels were not checked prior to admission. Comorbidities were not taken into account.
When? September.
For whom? University of Chicago.
What did the scientists study? Vitamin D levels of 500 Americans were tested. The researchers compared volunteer levels with the amount of coronavirus caught.
What did they find? Covid-19 rates 60% higher among people with low levels of “sun vitamin.”
What were the limitations of the study?
The researchers did not check for other compositional factors. It is not known whether the volunteers had vitamin D deficiency at the time of coronavirus testing. The age, work and place where people lived were not taken into account (factors that greatly increase the chances of contracting the virus).
When? September.
For whom? The University of Tehran, Iran, and Boston University.
What did the scientists study? Data analyzed from 235 patients hospitalized with Covid-19.
What did they find? Patients who had sufficient vitamin D (at least 30 ng / ml) were 51.5% less likely to die from the disease. They also had a significantly lower risk of falling seriously ill or needing ventilation. Patients who had a lot of nutrients also had less inflammation, often a deadly side effect of Covid-19.
What were the limitations of the study? No confusing factors were recorded, such as smoking, or the social economic status of all patients, which could affect the severity of the disease.
When? July.
For whom? Tel Aviv University, Israel.
What did the scientists study? In 782 people who tested positive for coronavirus, vitamin D levels before infection were assessed retrospectively and compared with healthy individuals.
What did they find? People with vitamin D levels below 30 ng / ml (optimal) were 45% more likely to test positive and 95% more likely to be hospitalized.
What were the limitations of the study? He did not examine the underlying health conditions and did not check vitamin D levels at the time of infection.
When? June.
For whom? Free University of Brussels.
What did the scientists study? Vitamin D levels were compared in nearly 200 hospitalized Covid-19 patients with a control group of more than 2,000 healthy people.
What did they find? Men hospitalized with the infection were significantly more likely to have vitamin D deficiency than healthy men of the same age. Deficiency rates were 67% in the group of patients with COVID-19 and 49% in the control group. The same was not found for women.
What were the limitations of the study? Independent scientists say vitamin D levels in the blood decrease when people develop serious illnesses, something the study did not take into account. This suggests that it is the disease that leads to reduced vitamin D levels in the blood in this study, not the other way around.
When? June.
For whom? Inha University in Incheon, South Korea.
What did the scientists study? All 50 hospital patients with Covid-19 were checked for levels of all vital vitamins and compared with a control group.
What did they find? 76% of them had vitamin D deficiency and a severe vitamin D deficiency (<10 ng / dl) was found in 24% of patients with Covid-19 and only 7% in the control group.
What were the limitations of the study?
The small sample size and the researchers never took into account the drop in vitamin levels when they fell ill.
When? June.
For whom?. Independent scientists in Indonesia.
What did the scientists study? Checking vitamin D levels in 780 hospital patients of Covid-19.
What did they find? Almost 99% of patients who died had vitamin D deficiency. Of the patients with vitamin D levels above 30 ng / ml (considered optimal), only the percentage died.
What were the limitations of the study? It was not reviewed by fellow scientists, a process that often reveals flaws in studies.
When? May.
For whom? University of Glasgow.
What did the scientists study? Vitamin D levels in 449 people at the UK Biobank who had confirmed Covid-19 infection.
What did they find? Vitamin D deficiency was associated with an increased risk of infection, but not after adjustment for co-founders such as ethnicity. It led the team to conclude that their “findings do not support a potential link between vitamin D concentrations and the risk of Covid-19 infection.”
What were the limitations of the study? Vitamin D levels were taken 10 to 14 years earlier.
When? May.
For whom? University of East Anglia.
What did the scientists study? Mean vitamin D levels in populations in 20 European countries were compared with Covid-19 infection and mortality rates at the time.
What did they find? The average level of vitamin D in each country was “strongly associated” with higher levels of Covid-19 cases and deaths. The authors then said, “The most vulnerable population group for Covid-19 is also the one with the most vitamin D deficiency.”
What were the limitations of the study? The number of cases in each country was affected by the number of tests performed, as well as by the different measures taken by each country to prevent the spread of the infection. And it only contemplated correlation, not causality.
When? May.
For whom? Northwestern University.
What did the scientists study? Approximate data from dozens of studies around the world that included vitamin D levels in patients with Covid-19.
What did they find? Patients with severe deficiencies are twice as likely to suffer major complications and die.
What were the limitations of the study? The number of tests performed affected cases and deaths in each country.