Insufficient vitamin D levels could leave individuals vulnerable to autoimmune disorders |

"Without this nutrient, people are more at risk of conditions such as rickets or osteoporosis -- highlighting its importance," Dr Grant explained.

He added that vitamin D serves multiple critical functions beyond bone health, stating: "Additionally, the vitamin is also crucial for supporting the immune system, helping the body protect against infections or diseases."

The GP warned that insufficient levels could leave individuals vulnerable to autoimmune disorders and respiratory infections, making supplementation particularly urgent as daylight hours continue to decrease.

This essential nutrient facilitates calcium absorption, maintains muscular strength and bolsters immune defences, with insufficiencies potentially triggering severe health conditions.