The Claim

In healthy adults aged 50–74, baseline vitamin D levels (25-(OH)D) are weakly associated with an increase in influenza-specific granzyme-B response from day 0 to day 75 following administration of the seasonal trivalent influenza vaccine containing A/California/H1N1-like virus, with a correlation coefficient of r=0.16 (p=0.04), indicating a minor statistical link between vitamin D status and the cellular immune response to the vaccine.

Source: Vitamin D, leptin and impact on immune response to seasonal influenza A/H1N1 vaccine in older persons

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
43score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Correlation
1 study reviewed
In plain English

People aged 50 to 74 who have a little more vitamin D in their blood before getting the flu shot tend to have a slightly stronger immune cell response to the vaccine a few weeks later — but the connection is very small.

See the scientific wording

In healthy adults aged 50–74, baseline vitamin D levels (25-(OH)D) are weakly associated with an increase in influenza-specific granzyme-B response from day 0 to day 75 after receiving the seasonal trivalent influenza vaccine containing A/California/H1N1-like virus, with a correlation coefficient of r=0.16 (p=0.04), suggesting a minor link between vitamin D status and cellular immune response to the vaccine.

What the research says

1 study
  1. Study: Vitamin D, leptin and impact on immune response to seasonal influenza A/H1N1 vaccine in older persons

    The study found that people with higher vitamin D levels before getting the flu shot had a slightly stronger immune cell response to the flu virus a few months later, which is exactly what the claim says.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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