Are Obesity and Birth Control Pills Causing Multiple Sclerosis?
According to two new studies released this week, obesity and birth control pills may play a part in the development of multiple sclerosis.
The first study found that those who were obese at the age of 20 were at twice the risk of developing MS in their lifetime. The study suggests a hormone called leptin, which helps stimulate appetite, could potentially be causing inflammation which triggers MS.
In the other study, a group of researchers found that women who had taken birth control pills may be 35 percent more likely to develop MS. The scientists also believe the hormones in contraceptive pills may be the culprit in the development of multiple sclerosis.
“These studies are pointing us to potential factors that might contribute to MS,” Timothy Coetzee told HealthDay. Coetzee is chief research officer at the National Multiple Sclerosis Society.
But, Coetzee also warns against leaping to any conclusions before more research is done. Both studies were able to show associations between hormones and MS, but there has yet to be a cause-and-effect connection discovered.
“There’s still a way to go with the research. We need more data from both studies,” said Coetzee, who was not involved in either study.
Multiple sclerosis is a disorder of the central nervous system brought about by an abnormal response of the immune system. It isn’t understood why, but MS causes the immune system to attack the protective sheath on nerve cells known as myelin, which can create symptoms ranging from fatigue and visual problems to motor difficulties and numbness.
In the obesity study, Argentinian researchers calculated the body-mass index (BMI) of 210 participants diagnosed with MS, along with 210 similar patients without MS. The study found that people who were obese at the age of 20 were more than twice as likely to develop MS at some point in their life compared to those who were healthier weights.
The study also found that participants with higher BMIs were more likely to have higher levels of leptin and lower levels of vitamin D, which have both been linked to signs of inflammation. It is believed this inflammation is one of the primary causes for the abnormal immune system response that creates MS.
“This study suggests that increases in leptin could have an exacerbating effect on the disease,” Coetzee said. However, he added that more study needs to be done to confirm the link. But, Coetzee conceded that “carrying extra weight isn’t good from a general point of view, and being more active, physically fit, and eating a good diet can enhance quality of life.”
The study focused on birth control pills and MS compared 305 women diagnosed with the disease or its precursor, known as “clinically isolated syndrome”, and compared them to 3,050 women without the disease. The researchers found that 29 percent of the women with MS used birth control pills compared with 24 percent of those without MS. Most of the women taking birth control pills used a combination pill containing both estrogen and progestin.
According to the findings, the women who used oral contraceptives were 35 percent more likely to develop MS.
“These results are demonstrating an association. I don’t want to say that we can firmly establish causality,” said study author Dr. Kerstin Hellwig, a postdoctoral researcher at Kaiser Permanente Southern California.
If the studies findings are correct, Hellwig says it is most likely due to an effect of the hormones on the immune system.
“At this point, women who take oral contraceptives shouldn’t be concerned about developing MS because of oral contraceptives. It may be one of many factors, but it’s not the one factor causing MS,” she said.
Both studies are set to be presented at the American Academy of Neurology’s annual meeting, which will be held April 26 to May 3 in Philadelphia. However, until they are published in peer-reviewed journals, the findings should be considered preliminary.