Too Much Vitamin D?
Supplements may provide too much vitamin D for the body to handle when certain diseases are present.
Vitamin D is essential for the absorption of calcium and the prevention of osteoporosis. Recent studies have shown that it may also boost the immune system and help to prevent cancer. The Vitamin D Council advises that most healthy people can benefit from a daily intake of 5,000 IU and that up to 10,000 IU may be required to maintain optimal blood levels.
But there is agreement in the medical community that too much vitamin D can exacerbate certain health conditions. And some researchers also believe it can compromise the immune system if the person has a chronic inflammation or autoimmune disease.
There are certain conditions where too much vitamin D in the form of supplements may cause elevated blood calcium (hypercalcaemia). These conditions include:
- primary hyperparathyroidism
- occult cancers (especially lymphoma),
- granulomatous disease (especially sarcoidosis).
Patients with these diseases should only take vitamin D supplements under the supervision of a doctor.
AUTOIMMUNE AND INFLAMMATORY DISEASES
More controversially, some researchers argue that low vitamin D levels are caused by various inflammatory and autoimmune diseases and that vitamin D supplements may further dampen the immune system.
Trevor Marshall, who is at the forefront of this movement, argues that inflammatory diseases are caused by bacteria that both attack the immune system and impact the metabolism of vitamin D. The Marshall Protocol, created to treat these diseases, focuses on the use of antibacterial medication and avoidance of ingested vitamin D (from supplements and fortified foods) as they are believed to hamper recovery. Exposure to sunshine is also discouraged for those suffering from photosensitivity, which is common with many inflammatory diseases and may worsen with the Marshall Protocol. The diseases recommended for treatment with the Marshall Protocol include:
- acute respiratory tract infections
- cancer (breast, colorectal, prostate, lung, non-Hodgkins’s lymphoma, ovarian)
- celiac disease
- Crohn’s disease
- Cystic fibrosis
- Graves disease
Many people are critical of the Marshall Protocol because it challenges conventional thinking about these diseases and has also not been validated by rigorous scientific research. Others have benefited from the protocol and are strongly encouraging further research.