People living in the sun and have higher levels of vitamin D have less risk of developing multiple sclerosis (MS), according to this Canadian study published in the February 8 edition of the journal Neurology, the journal of the American Academy of Neurology. But more interestingly, sun exposure and vitamin D levels are two independent factors for reducing the risk of disease development.
MS is a chronic disease of the brain and spinal cord, usually with recurrent attacks of symptoms. "Previous studies have suggested similar results, but this is the first study conducted on patients with early symptoms of MS but have not yet been diagnosed," says study author, Professor Robyn Lucas, the National University in Canberra (Australia). "Other studies have focused on people who had MS, it was not possible to know whether the disease has led them to change their lifestyle habits, including exposure to sunlight or diet."
This study was conducted on 216 people aged 18 to 59 who had a first event with symptoms such as SAP, with a control group of 395 participants with no symptoms of MS in the same age, same-sex and same region of Australia. Participants filled sun exposure in each period of their lives, the researchers measured the amount of skin damage from sun exposure and the amount of melanin in their skin. Levels of vitamin D were measured by blood tests.
The risk of a first event, diagnosed by a doctor, ranged from approximately 2 to 9 new cases per 100,000 persons per year, in this study. Exposure to UV light of participants ranged from 500 to more than 6,000 kilojoules per square meter.
The researchers found
· That the risk of having an event type is diagnosed in September reduced by 30% for each increase of 1000 kJ UV
· That persons with skin lesions from sun exposure is a risk reduced by 60% of developing a first event compared with participants without lesions by exposure to UV,
· That people with higher vitamin D levels are also less likely to have experienced a first episode of MS symptoms than participants with lower levels of vitamin D.
Overall, differences in exposure to sunlight, vitamin D and skin type represents an increase of 32% for diagnosing a first event in September Effects associated with exposure to sunlight and vitamin D levels were 2 factors independent of each other on the risk of first event.
Nevertheless, the researchers remind us that we must limit its exposure to the sun because of the risk of skin cancer and the risks of tanning beds to far outweigh the benefit of protection against MS.