Pancreatic cancerPatient friendly summary

  • Incidence and death rates of pancreatic cancer are lower in people with more exposure to solar UVB light.
  • Higher vitamin D levels would likely reduce the risk of pancreatic cancer.

Pancreatic cancer is cancer of the pancreas, the organ that produces insulin.

Approximately 44,000 people in the United States are diagnosed with cancer of the pancreas each year. It is one of the most deadly cancers and causes as many as 37,000 deaths annually. The disease is often diagnosed at an advanced stage. By then, treatment may not be effective.

Risk factors

Some of the more important risk factors for this cancer include:

  • Diet high in simple carbohydrates and meat: Simple carbohydrates (white rice, baked goods) are foods that turn into sugar quickly. Sugar, meat, and fat contribute to the metabolic syndrome. This is characterized by extra abdominal fat and insulin resistance. This syndrome increases the risk of many diseases.
  • Obesity: This health threat may also contribute to the metabolic syndrome.
  • Smoking: Smoking contributes to the risk of pancreatic cancer.

A diet high in vegetables is associated with a reduced risk of pancreatic cancer

Sunlight exposure and pancreatic cancer risk

Several studies have researched solar ultraviolet-B (UVB) light, vitamin D, and pancreatic cancer. The studies concluded that:

  • There was a lower incidence and death rate from pancreatic cancer in people exposed to higher levels of solar UVB light. These studies appear to be reliable and accurate. They researched the effects of UVB light during an entire lifetime. There have been similar results in Japan and the United States.
  • People who live in warm, sunny climates produce adequate levels of vitamin D. They have a higher risk of nonmelanoma skin cancer. But they have a lower risk of pancreatic cancer.

Vitamin D and pancreatic cancer

Vitamin D levels

Two Harvard studies found a correlation between vitamin D and pancreatic cancer:

  • One study compared people taking 150 vs 600 international units (IU) (3.8 vs 15 mcg)  vitamin D per day. There was a 40% lower cancer risk in people who took more vitamin D.
  • The other study found a 35% lower risk for those with higher vitamin D blood levels.

Other studies using a single value of vitamin D blood level did not find beneficial effects of vitamin D. However, the long follow-up times after blood level measurement greatly reduces the value of the study.

How vitamin D works

Vitamin D has been shown to block the growth of cancer tumors. Vitamin D is processed by the liver. The body then produces calcitriol, an active form of vitamin D. Calcitriol provides numerous benefits against cancer. This form of vitamin D encourages cells to either adapt to their organ or commit apoptosis (cell suicide). Calcitriol also limits blood supply to the tumor and reduces the spread of cancer. 


High levels of vitamin D are associated with a lower risk of pancreatic cancer based on both observational studies of individuals and geographic studies of populations.

Based on studies of breast, colon, and rectal cancer, vitamin D levels above 40 ng/mL (100 nmol/L) reduce the risk of cancer. Thus, maintaining vitamin D blood levels above 40 ng/mL may reduce the risk of pancreatic cancer. 

Taking 1000–4000 international units (IU) (25–100 mcg)/day of vitamin D may be associated with reduced pancreatic cancer risk.

Vitamin D and calcium

Studies have shown that taking both vitamin D and calcium provides additional cancer protection against many types of cancer. Calcium intake of more than 1000 mg/day from either diet or supplements is recommended.

Patients in one study took daily doses of 1100 IU (27.5 mcg) vitamin D and 1450 mg calcium. These patients had a 77% reduction in the incidence of all types of cancer between the ends of the first and fourth years of the study.


People with higher vitamin D levels at time of cancer diagnosis have a higher survival rate. This is true for people with many types of cancer. Studies suggest that increasing vitamin D levels after cancer diagnosis would improve chances of survival.

Some treatment centers are now giving at least 5000 IU (125 mcg)/day vitamin D to patients with cancer. Outcome results have yet to be published.

Find out more…

Do you want to find out more and see the research upon which this summary is based?  Read our detailed evidence summary on Pancreatic cancer.

Page last edited: 05 August 2011