Tom Hanks, 57, revealed Monday on The Late Show with David Letterman that he has been diagnosed with Type 2 diabetes.
"I went to the doctor and he said, 'You know those high blood sugar numbers you've been dealing with since you were 36? Well, you've graduated. You've got type 2 diabetes, young man,'" Hanks told Letterman.
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But despite the serious news, he kept his sense of humor.
"It's controllable," he assured the audience. "Something's gonna kill us all, Dave."
But he also commented that losing weight would not be a viable option for him.
"My doctor said 'If you can weigh as much as you weighed in high school you will essentially be completely healthy and will not have Type 2 diabetes,' and I said, 'Well, I'm gonna have Type 2 diabetes 'cause there is no way I can weigh as much as I did in high school.'"
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Hanks joked that he weighed only 98 pounds in high school.
But despite the weight jokes, Hanks looked noticeably trimmer during his latest appearance to promote Captain Phillips, which hits theaters Friday.
UPDATE: He later took to Twitter to confirm his diagnosis, once again reassuring many of his fans who expressed concern after the news broke Tuesday.
"Yep, I have #2 diabetes. Type 1 is VERY SERIOUS! Type 2 I can manage with good habits. I shall! Hanx," he wrote.