Mariah Carey is reportedly "sick with worry" about her husband Nick Cannon.

Nick has suffered a string of health problems lately, most recently being hospitalised for blood clots on his lungs. He's been told to slow down by doctors and has taken the decision to leave his New York City radio show.

Although Nick is taking steps to regain his health, Mariah is said to be terrified he may fall ill again.

"I've heard her say that if something happened to Nick, she doesn't know how she would survive it. She's sick with worry every hour of every day," a source told National Enquirer.

Nick works as a stand-up comedian and singer, hosts the America's Got Talent TV show and also has other business interests. His busy career means he rarely has time to relax with Mariah and their twins Monroe and Moroccan.

Falling ill has apparently scared 31-year-old Nick, and Mariah hopes he's now been jolted into taking his health more seriously.

"She's been telling him [to slow down] for a while," another insider revealed.

"Maybe Nick is beginning to see the light. Between his kidney and heart problems, he's had to face his own mortality at the incredibly young age of 31 and Mariah's scared to death for their future."