One of the important effects vitamin D has on the body is its influence on the immune system. For a long time, researchers only suspected the positive influence of the vitamin on the human immune system. In recent years, however, the suspicion has become certain. Vitamin D probably has these effects on the immune system:

• Vitamin D helps T-cells prepare a strong immune response.
• Low vitamin D levels are associated with common infections such as the flu and the common cold.
• Regular intake, for example through food supplements, reduces the risk of inflammation of the respiratory tract.
• A deficiency in the vitamin can exacerbate autoimmune diseases such as multiple sclerosis.
• The development of type 2 diabetes could be favored by vitamin D deficiency.

Note: Most studies specifically emphasize that vitamin D deficiency has negative effects on the immune system. However, the effects of a sufficient or high vitamin D level have not been researched to date.

See also:

• Vitamin D
• Vitamin D and Bone Stability
• Vitamin D and Covid-19

Sources:

• Vitamin D and the immune system
• Overwhelming evidence supports Vitamin D's immune function benefits
• Vitamin D study sheds light on immune system effects
• Effect of Monthly High-Dose Vitamin D Supplementation on Acute Respiratory Infections in Older Adults: A Randomized Controlled Trial
• Harvard University on Vitamin D