Is vitamin D associated with complications in people with diabetes?

This study looked at whether low levels of vitamin D increased complications for patients with type 2 diabetes (T2D). It found that foot ulcers were more common for patients who had low vitamin D (LVD).

T2D is a condition in which the body cannot control levels of glucose (sugar) in the blood. Over time, high blood glucose can damage the walls of blood vessels. Delicate small blood vessels, such as those in the eyes and the kidneys, are particularly vulnerable. Diabetes can also lead to damage of the hands and feet, causing numbness and raising the risk of ulcers.

Vitamins and nutrients play an important role in chronic diseases such as diabetes. Vitamin D is best known for its importance to bone health. However, vitamin D is also important for tissue growth and blood vessel health. It even plays a role in the sensitivity to insulin, the hormone regulating blood glucose. Inadequate vitamin D is very common, particularly during the winter and in northern latitudes. Some studies indicate vitamin D is important to diabetes complications involving blood vessel health. However, whether low vitamin D (LVD) is related to complications in people with diabetes remains under investigation.

This study included 4,284 patients with T2D. All patients were given blood tests including vitamin D levels, glucose, and cholesterol. They were also interviewed about their health history. 71.7% of participants had low levels of vitamin D (below 50 nmol/L).

Foot ulcers were more common for patients with LVD (6.3% vs. 4.1%). This connection was significant even after adjusting for age, smoking, cholesterol, medications, and other factors.

Patients who had LVD had retinal eye damage more often (29.6% vs. 25.9%). However, after adjusting for factors such as blood pressure and medications, this difference could have been due to chance.

This study found that low vitamin D levels are related to foot ulcers for patients with T2D.

Retinal eye damage and kidney damage both seemed significantly related to VDD when simple adjustments were made for age and sex. However, these relationships were not significant when more complicated adjustments were used. This study included Chinese people only. The results may not apply to all populations.

Talk to your doctor about your vitamins and supplements, and whether a vitamin D or multivitamin supplement is appropriate for you.