Rob Kardashian was released from the hospital Thursday after reportedly receiving treatment for diabetes, and his condition is more common for young people than you might think.

Kardashian was hospitalized with Type 2 diabetes last year, and has been attempting weight loss and a healthier lifestyle to combat it, according to CNN.

Both Type 1 and 2 diabetes — conditions which inhibits the body's ability to process sugar from food — can have serious consequences, including heart disease, blindness, kidney failure, and amputations. It's the seventh leading cause of death in the U.S.

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"When you have diabetes, your body either doesn't make enough insulin or can't use its own insulin as well as it should," according to the Centers for Disease Control and Prevention. "This causes sugars to build up in your blood. This is why many people refer to diabetes as 'sugar.'"

People who have diabetes experience extreme thirst and hunger, weight changes, blurry vision, and extreme fatigue among other symptoms. The CDC estimates that there are 29 million people in the U.S. who have diabetes.

Millions of young people have diabetes.

Kardashian, who is only 29 years old and has already been hospitalized for diabetes multiple times, is one of about four million Americans between the ages of 20-44 to suffer from the ailment. Further, about 208,000 children and adults younger than 20 have been diagnosed with diabetes.

These numbers clash with the typical depiction of diabetes sufferers presented in advertisements and public-service announcements — think Wilford Brimley's role as spokesman for Liberty Medical’s diabetes testing supplies.

Why don't people know they have diabetes?

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Of the 29 million Americans the CDC says have diabetes, 21 million of them are diagnosed and another estimated 8 million don't know they have it. Regular health care visits are key to a diagnosis. Before someone develops full blown diabetes they have a condition called pre-diabetes, which often doesn't present any symptoms, but can be tested for.

"Pre-diabetes is a condition in which blood glucose levels are higher than normal, but not high enough to be classified as full-blown diabetes," according to the Joslin Diabetes Center.

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If a health care provider doesn't explain the seriousness of pre-diabetes effectively, a patient could fail to embrace the lifestyle changes capable of preventing the full-blown condition. If the person has sporadic health care visits, they could develop diabetes and not realize it.

“The health care provider has to tell the patient that they don’t meet the criteria for diabetes but they aren’t quite out of the woods, which can be a challenging concept to get across,” Dr. Laura Rosella, a public health researcher at the University of Toronto, told the Huffington Post last year. “This challenge could explain the low awareness.”

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