- UVB light may reduce the risk of Hodgkin’s lymphoma.
- Vitamin D may lower Hodgkin’s risk by strengthening the immune system and reducing viral infections.
Hodgkin’s lymphoma (or Hodgkin’s disease) is a cancer of the lymphocytes, a type of white blood cell. Symptoms may include recurrent fever, itchy skin, night sweats, weight loss, and enlarged lymph nodes.
The primary risk factor for Hodgkin’s lymphoma is Epstein-Barr virus. This is the same virus associated with multiple sclerosis and infectious mononucleosis. There is strong evidence that vitamin D reduces the risk of multiple sclerosis.
Sunlight exposure and Hodgkin’s lymphoma risk
A number of studies have found a connection between ultraviolet-B (UVB) light and the risk of Hodgkin’s lymphoma:
- The incidence of Hodgkin’s is highest in the late winter/early spring. There is less sunshine, and vitamin D levels are at their lowest. Solar UVB light is the primary source of vitamin D for most people.
- In Norway, 15% of people diagnosed with Hodgkin’s in the summer had improved 36-month survival rates compared to those diagnosed in the winter.
- In Sweden, UVB exposure before 20 years of age was related to reduced risk of Hodgkin’s lymphoma. In Canada, higher UV exposure was also linked to reduced Hodgkin’s risk.
- One U.S. study found that higher UVB levels in the winter may lower Hodgkin’s risk. Another U.S. study found similar results for people exposed to higher annual solar UVB levels.
Vitamin D and Hodgkin’s lymphoma
Vitamin D levels
The dose-response relationship between vitamin D levels and Hodgkin’s risk has not been adequately studied. However, Hodgkin’s occurs more often in the winter, when there is less light. This indicates that vitamin D levels below 20-30 ng/mL (50-75 nmol/L) may be linked to increased disease risk.
How vitamin D works
Vitamin D may reduce the risk of Hodgkin’s by:
- Strengthening the immune system (Vitamin D triggers cathelicidin and defensins. These two proteins reduce viral infections.)
- Reducing the amount of inflammation associated with viral infections.
There are no reported studies of using vitamin D supplements to reduce the risk of cancer. However, the positive effects of vitamin D on influenza and multiple sclerosis have been confirmed. Keeping vitamin D levels above 30-40 ng/mL (75-100 nmol/L) may lower the risk of Hodgkin’s. Maintaining high levels is especially important in the winter.
Vitamin D and calcium
Approximately 10% to 20% of people with Hodgkin’s have hypercalcemia. This is a condition of too much calcium in the blood. Calcium is regulated in part by calcitriol, the hormonal version of vitamin D. Calcitriol levels are higher for both low and high values of vitamin D in the blood. Hypercalcemia is a serious but correctable complication. It occurs in 10% to 20% of people with Hodgkin’s. Symptoms include poor appetite, frequent thirst and urination, constipation, and nausea and vomiting. The person may also have pain, especially on the sides, near the kidneys. Muscle twitching and weakness is also common. If any of these symptoms develop, immediately stop taking vitamin D and consult a doctor. Vitamin D blood levels fall to half value in about four weeks.
According to studies, raising vitamin D levels after diagnosis of Hodgkin’s should help improve prognosis. It is important to monitor for any possible side effects of excess calcium.
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: 05 August 2011