“There’s an increase, but not a guarantee,” of developing MS when a family member has it, Dr. Greenfield says. Women’s greater susceptibility to MS overall is thought to be associated with hormonal changes, Dr. Mateen says.

Smoking

Low Levels of Vitamin D

In response to such studies, many doctors have begun recommending vitamin D supplements for people who have MS, particularly for those who are vitamin D deficient.

Geographic Location

People who live in more temperate climates — like Europe, southern Canada, and the United States — have a slightly higher risk of MS than those who live closer to the equator, Greenfield says. RELATED: Why Your ZIP Code Matters if You Have Multiple Sclerosis

Obesity

Having an Autoimmune Condition

Mateen says that while these other conditions don’t cause MS, if you have one autoimmune disease, you have a higher risk of getting a second one, and MS is generally considered an autoimmune disease.

Epstein-Barr Virus

RELATED: What Does the Epstein-Barr Virus Have to Do With MS?

Concussion in Adolescence

While there’s more to be learned about the connection between MS and concussion, the researchers commented that their results emphasized the importance of protecting young people from head injuries.

Race

Age

Living Near Major Roads

Living near green spaces, however, was found to have some protective effects against MS and the other disorders. “With MS, there isn’t a lot to monitor or evidence that if you change your diet or lower stress or exercise regularly you have less chance of developing it,” she says. But she does have some advice for family members of persons with MS:

If you have a symptom that might be caused by MS, get it checked out.Avoid smoking and secondhand smoke.Try to maintain a healthy weight and make sure you’re getting enough vitamin D.

“People should stay mentally and physically active so if someone does get MS, they will have greater physical and mental reserves to deal with it,” Mateen says. RELATED: Can You Prevent Multiple Sclerosis?

Resources We Love

National Multiple Sclerosis Society The National Multiple Sclerosis Society is a nonprofit organization that aims to find a cure for MS. It also provides information about symptoms, diagnosis, treatment, resources, and support for MS. Mayo Clinic The Mayo Clinic is a nonprofit organization that specializes in clinical practice, education, and research. Its website offers information about the symptoms, causes, risk factors, complications, diagnosis, and treatment of MS.