Vitamin D is critical to our overall health, and now scientists have made some significant discoveries about how early life deficiency can trigger issues with the body’s immune system.
McGill University in Canada researchers used a combination of analysis techniques to examine genetically engineered mice that do not naturally produce vitamin D.
They found that the small organ that trains our immune system—the thymus—ages faster in these mice, allowing self-attacking immune cells to run amok.
The thymus has a crucial role in educating the body’s T cell defense force not to attack healthy cells, and we are also aware that vitamin D is linked closely to this process. Now, these biological relationships are much clearer.
“Our findings bring new clarity to this connection and could lead to new strategies for preventing autoimmune diseases,” says John White, McGill University physiologist.
Mice unable to produce vitamin D had a thymus containing fewer and smaller cells. The organ also showed biological signs of premature aging and decreased levels of a critical autoimmune regulator.
It shows how vitamin D deficiency can result in less protection against autoimmune diseases, where the body mistakenly attacks its own cells, leading to health complications.
“An aging thymus leads to a leaky immune system,” White says. “This means the thymus becomes less effective at filtering out immune cells that could mistakenly attack healthy tissues, increasing the risk of autoimmune diseases like type 1 diabetes.”
Based on prior research, experts believe vitamin De is particularly crucial in children, as the all-important T cell training in the thymus happens up until age 20. As we age, the benefits of vitamin D — at least in regard to this — seem much less clear-cut.
This makes these discoveries especially relevant to younger individuals. Although this has only been shown so far in mice, our thymus functions in a similar way, so there are adequate reasons to believe the same biological processes are present in humans.
Researchers already have plans to study how vitamin D affects the human thymus — which hasn’t been studied before.
There is some debate about vitamin D supplements’ effectiveness, though the overall consensus is they can be beneficial if an individual is deficient in specific health areas.
We now know that lacking this crucial vitamin, possibly through a lack of daily sunlight, can put one’s immune system at a disadvantage from an early age.
“If you have a young child, it’s important to consult with your healthcare provider to ensure they’re getting enough,” White says.
This research was published in Science Advances.
