What causes MS?
Multiple Sclerosis causes are unknown; however evidence suggests that the condition may result from a combination of genetics and environmental factors:
Multiple Sclerosis occurs more frequently in areas that are farther from the equator. Scientists studying disease patterns are exploring if variations in geography (sunlight duration, changes in temperature and humidity, etc.), demographics (age, gender, ethnicity, migration patterns, etc.), diet, infection causes, exposure to environmental toxins may cause or exacerbate MS [1-2].
So far, no specific environmental factor has been proven to trigger the disease; it is likely caused by several factors.
There is growing evidence that the more sunlight exposure we have, and consequently the higher levels of naturally-produced vitamin D (which is thought to help immune function), the lower MS risk [1-2].
Population migration studies support the notion that exposure to some environmental agent before puberty may predispose a person to develop Multiple Sclerosis later on. As such, people born in a MS high-risk area seem to acquire a lower risk if they move to an area with a lower risk before the age of 15 [1-2].
Studies have shown that smoking increments the risk of developing MS and correlates with more severe condition and faster disease progression [1-2]. Moreover, exposure to other toxic substances, like solvents or heavy metals, has been associated with MS development, but without reaching clear conclusions .
It has also been reported that too much salt may prompt the immune system causing autoimmune diseases [4-5].
Finally, even though infections have been often mentioned by doctors and researchers as a potential Multiple Sclerosis cause, this theory has not been scientifically proved [1-2].
Is MS hereditary? Genetic Factors
Although MS is not hereditary, people having a first-degree relative, such as a sibling or parent, with the disease have a higher risk of developing the condition. In fact, certain genes appear more frequently in populations with increased rates of MS and common genetic factors have also been found in some families with more than one person suffering the disease. For this reason, researchers speculate that predisposition to develop MS is influenced by genetic factors [1, 6-8].
1. In: http://www.nationalmssociety.org/What-is-MS. Accessed 25/01/2017.
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