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.
Nurse studies are historically known for being high quality due to the large numbers of participants, long periods measurements are taken and the increased reliability in the reporting this population can provide. However, the researchers admit that there are limitations to the study.
The information from the participants was self-reported and represents one type of group of women. Dermatologists did not examine the patients and diagnose their psoriasis.
Other variables such as how much time was spent outdoors exposed to UV light might be a contributing factor though less likely since women who walked outdoors had similar exposure.
This study adds another piece of data to the body of research for psoriasis. Other research has shown that smoking, alcohol and obesity can worsen psoriasis. However, in some ways this study opens up more questions than it answers.
What is it about vigorous exercise instead of moderate amounts that makes a difference?
Is it that those who perform it live healthier lives, eat better food or have even lower levels of stress?
It is important to realize that regular exercise that is not as vigorous still provides health benefits and can contribute to stress reduction, which is known to aggravate psoriasis. Not everyone is able to exercise so vigorously.
Further studies about the effect of vigorous exercise and psoriasis will be needed to clearly identify what specifically contributes to the large reduction of risk to those who have greater tendencies to develop this illness.
Sources:
Understanding Psoriasis -- the Basics. WebMD. Retrieved May 27, 2012.
http://www.webmd.com/skin-problems-and-treatments/psoriasis/understandin...
Your Skin and Psoriasis. WebMD. Retrieved May 27, 2012.
http://www.webmd.com/skin-problems-and-treatments/psoriasis-8/causes
Vigorous Exercise Might Keep Psoriasis at Bay. Retrieved May 27, 2012.
http://health.usnews.com/health-news/news/articles/2012/05/21/vigorous-e...
Vigorous Physical Activity Associated With Reduced Risk of Psoriasis. Sciencedaily.com. Retrieved May 27, 2012.
http://www.sciencedaily.com/releases/2012/05/120521163843.htm
Activity Cuts Psoriasis Risk in Women. Medpage Today. Retrieved May 27, 2012.
http://www.medpagetoday.com/Dermatology/Psoriasis/32829
Frankel, C Hillary et al. The Association Between Physical Activity and the Risk of Incident Psoriasis. Arch Dermatol. 2012;():1-7. doi:10.1001/archdermatol.2012.943. Published online May 2012
http://archderm.jamanetwork.com/article.aspx?articleid=1158558
Michele is an R.N. freelance writer with a special interest in woman’s healthcare and quality of care issues. Other articles by Michele are at www.helium.com/users/487540/show_articles/
Edited by Jody Smith