"Well, it takes a little bit more than that."
However, Hanks is hopeful that he can beat the disease.
"My doctor says if I can hit a target weight, I will not have Type 2 diabetes any more," he said.
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The actor became a father at 21 and said that starting a family at such an early age meant that he never became a "s**tfaced artist".
Hanks, now a father-of-four, said: "I'm lucky. I was in charge of offspring at a very early age, so I didn't have the luxury of being able to get stoned a lot.
"And I never drank too much. I was never what I call a s**tfaced artist."
The actor said he doesn't regret that because he didn't think it was more fun to be intoxicated or stoned.
"I thought it was more fun just to be seeing what was going on. I did my share, but it didn't become a habit," he said.
- PAA