Parkinson's linked to vitamin D

Parkinson's gets progressively worse

Scientists are testing whether vitamin D supplements can ease symptoms of Parkinson's disease.
A US team found 55% of Parkinson's patients had insufficient levels of vitamin D, compared to 36% of healthy elderly people.
However, the Emory University researchers do not yet know if the
vitamin deficiency is a cause or the result of having Parkinson's.
The study appears in the journal Archives of Neurology.
Parkinson's disease affects nerve cells in several
parts of the brain, particularly those that use the chemical messenger
dopamine to control movement.
The most common symptoms are tremor, stiffness and slowness of movement. These can be treated with oral replacement of dopamine.
Previous studies have shown that the part of the brain affected
most by Parkinson's, the substantia nigra, has high levels of the
vitamin D receptor, which suggests vitamin D may be important for
normal functions of these cells.
Sunlight
Vitamin D is found in the diet, but is primarily formed in the skin by exposure to sunlight.
However, the body's ability to produce the vitamin decreases with age, making older people more prone to deficiency.
One theory is that people with Parkinson's may be particularly
vulnerable because their condition limits the amount of time they spend
out of doors.
However, scientists say it may also be possible that low
vitamin D levels are in some way related to the genesis and origin of
the disease.
The researchers examined vitamin D levels in 100 people with
Parkinson's, 100 with Alzheimer's disease and 100 who were healthy. The
groups were matched for age, and economic circumstance.
Among the Parkinson's group 23% of patients had vitamin D
levels so low that they could be described as deficient. In the
Alzheimer's group the figure was 16%, and in the healthy group 10%.
The researchers said the findings were striking because the
study group came from the South West of the US, where sunny weather is
the norm.
'Intriguing finding'
Researcher Dr Marian Evatt said: "We found that vitamin D
insufficiency may have a unique association with Parkinson's, which is
intriguing and warrants further investigation."
Dr Kieran Breen, director of research, Parkinson’s Disease
Society said: "Further research is required to determine at what stage
the deficiency in vitamin levels occur in the brains of people with
Parkinson's and whether the provision of a dietary supplement, or
increased exposure to sunlight may help alleviate symptoms or have an
affect on the rate of the condition's progression.
"This would help us answer the question as to whether the
decrease in vitamin D levels in Parkinson’s is a cause or effect of the
condition."
Doctors have known for decades that vitamin D plays a role in bone formation.
More recently, scientists have been uncovering its effects
elsewhere, including producing peptides that fight microbes in the
skin, regulating blood pressure and insulin levels, and maintaining the
nervous system.
Low vitamin D levels also appear to increase the risk of
several cancers and auto-immune diseases such as multiple sclerosis and
diabetes.


http://news.bbc.co.uk/2/hi/health/7666749.stm