Updated

More than one in four Americans are at risk for developing type 2 diabetes – and one-third of them don’t even know they have it.

Trying to get that message out is hip-hop legend Rev Run, who became an ambassador for Novo Nordisk’s “Ask.Screen.Know” campaign, which encourages Americans to get screened for the preventable disease. Run, whose real name is Joseph Ward Simmons, is a member of the influential hip-hip trio Run D.M.C., and he’s starred in a few reality TV shows, including MTV's reality show "Run's House."

Run decided to become involved because he is at risk for the disease – being over the age of 45 and African-American. His father had it, and Run, 48, is determined not to follow in his footsteps.

“Most people go to the doctors, and sometimes they don’t even ask to get screened,” Run told FoxNews.com.

Run said when he started working with Novo Nordisk, he hadn’t yet been screened for diabetes, which made him a little nervous.

“I was scared' I was concerned,” Run said. “I’m a spiritual guy, so I was thinking, 'Is this a sign?'”

Run said many people are afraid to be screened, but he tells them to do it for their family. Run is married to Justine Jones, and he has six children. His brother is another hip-hop legend, Russell Simmons, co-founder of Def Jam Records.

“First of all, I’m African-American, and I’m over 45,” Run said of his decision to get screened. “I’m getting up there in pounds.”

He has also made a conscious decision to go back to the gym and eat healthier – fruit as a late-night snack, instead of popcorn – and as a result, he's lost more than 22 pounds.

“I stopped eating all the bread, and changing all the things I knew could make my cholesterol and sugar intake so high,” he said. “What you don’t confront, you can’t fix.”

Run is bringing his message to churches around the country, and he even spoke at the Rock and Roll Hall of Fame. He wants people to know they can’t just “walk until the wheels fall off,” and that diabetes is a curable disease.

He encourages people to visit askscreenknow.com, where they can find out more information about the disease, learn more about risk factors and how to get screened.

“People are scared to know the answer,” Run said, “but do it for your family.”

Visit the Ask.Screen.Know website for more info.