Many individuals who have MS are very heat-sensitive. Exposure to increased heat temporarily worsens their symptoms. This may manifest as increased weakness, fatigue, vertigo, impaired concentration, urinary urgency, and/or blurred vision. This is known as Uhthoff’s phenomenon.
Thankfully, these temporarily increased symptoms are reversible. They’re not an indication of increased MS lesions, nor are they evidence of disease progression.
As a result of heat-induced symptom worsening, individuals with MS may limit their outdoor activities during warmer periods of weather. This results in reduced exposure to sunlight, which subsequently diminishes Vitamin D production.
Geographical location plays a role in the incidence of MS; the further away from the equator that you live, the greater your chances of developing MS. Reduced exposure to sunlight, with less Vitamin D production, is correlated with the incidence of MS.
Preliminary research suggests that MS patients who have higher Vitamin D levels may experience reduced symptom severity. Additional research is required to determine how enhanced Vitamin D levels may impact the overall course of MS. Personally, I was determined to have a Vitamin D deficiency.
Given that my MS symptoms are very heat-sensitive, I consistently avoid being outside in the summer. Since my fair skin burns very easily, I also avoid sun exposure. Furthermore, some of my prescription medications increased my susceptibility to sunburn. My specialist has prescribed Vitamin D3 (2,000 I.U. per day).