Peripheral vascular diseasePatient friendly summary

  • African-Americans have higher rates of peripheral vascular disease than white Americans. Dark skin blocks UVB light that makes vitamin D.
  • People with higher vitamin D levels may have a reduced risk of peripheral vascular disease.

Peripheral vascular disease (also commonly known as Peripheral arterial disease) occurs when plaque builds up in the arteries.

Plaque is made up of fat, cholesterol, calcium, fibrous tissue, and other substances in the blood. Over-time, plaque causes the arteries to harden and narrow. This condition is called atherosclerosis. The arteries can no longer carry oxygen-rich blood throughout the body. Peripheral vascular disease usually affects the legs.

Risk factors

The main risk factor for peripheral vascular disease is type 2 diabetes mellitus (T2DM). Factors that contribute to the risk of T2DM include diets high in refined carbohydrates and/or fat and low vitamin D blood levels.

Sunlight exposure and peripheral vascular disease risk

African-Americans have higher rates of peripheral vascular disease than white Americans. Possibly this is because:

  • Dark skin does not absorb ultraviolet-B (UVB) light from the sun as readily as light skin. As a result, African-Americans have lower vitamin D blood levels than white Americans.
  • Higher rates of diabetes, perhaps because of consuming more high-fat and sugary foods.

Vitamin D and peripheral vascular disease

Vitamin D levels

Several studies found that people with lower vitamin D levels have increased risk of peripheral vascular disease:

  • In a U.S. study, the rate of peripheral vascular disease was 40% for each 10 ng/mL (25 nmol/L) decrease in vitamin D level below 30 ng/ml (75 nmol/l).
  • In a Utah study, people with low vitamin D levels had nearly twice the risk of developing peripheral vascular disease compared to those with adequate vitamin D levels.

How vitamin D works

While the mechanism is uncertain, vitamin D might lead to lower peripheral vascular disease risk by reducing:

  • Hypertension
  • Inflammation
  • Hardening and cell growth inside the lining of the blood vessel walls
  • Risk of type 2 diabetes


There is some evidence that higher vitamin D blood levels may reduce the risk of peripheral vascular disease.

Based on results for cardiovascular diseases and diabetes, vitamin D blood levels should be greater than 30–40 ng/mL (greater than 75–100 nmol/L) to significantly lower PAD risk.

Taking 1000–5000 international units (IU) (25–125 mcg)/day of vitamin D3 (cholecalciferol) may raise the levels to this amount. The rule of thumb is that each 1000 IU (25 mcg)/day of vitamin D increases vitamin D blood levels by 6–10 ng/mL (15–25 nmol/L). However, there is considerable variation from person to person. Three months of supplements are recommended. To determine proper dosage, vitamin D levels should be measured before and three months after taking vitamin D3 supplements or increasing UVB exposure.


There are no reported studies using vitamin D to treat peripheral vascular disease. However, higher vitamin D levels might reduce the severity of peripheral vascular disease.

Find out more...

We will be adding a detailed evidence summary on this topic in the near future.  Please check back soon to find out more.

Page last edited: 17 May 2011