Psoriasis is an autoimmune disease where the skin becomes inflamed, itchy and scaly patches develop. It is unknown what causes psoriasis but it is believed that there is a genetic tendency to the disease and that emotional stress plays role.
A 2011 Harvard study has shown that vigorous exercise of up to three hours a week may reduce the risk of developing psoriasis by 25 to 30 percent.
The researchers collected data on 867,000 women from the Nurses Health study II over 14 years of followup. During that time period, there were 1026 new cases of psoriasis.
The participants reported the amount of time each week they participated in different types of exercise through questionnaires completed twice a year.
The researchers calculated the MET (metabolic equivalent task) per week for each women based on the type of exercise and how vigorously it was performed. Scores that equaled an MET of 6 or higher were classified as vigorous exercise.
"Our results suggest that participation in at least 20.9 MET (metabolic equivalent task)-hours per week of vigorous exercise, the equivalent of 105 minutes of running or 180 minutes of swimming or playing tennis, is associated with a 25 percent to 30 percent reduced risk of psoriasis compared with not participating in any vigorous exercise," the authors commented in Science Daily.
The researchers found that only exercises such as running, aerobic exercises or calisthenics reduced the women’s risk of developing psoriasis while walking did not lower the risk.
The greatest reduction was seen in those women who reported running for at least an hour each week.
“Why exercise is tied to a lower risk of psoriasis isn’t known for sure,” said the researchers in a Healthday report. They indicate that while there is an association, there is “not a cause-and effect relationship between exercise and the skin disorder.”
Dr. Quersha from the study team postulated that physical activity might provide an increased anti-inflammatory benefit, which has been observed to help other conditions with inflammation such as diabetes, colon cancer, coronary heart disease and breast cancer.