Arthritis sufferer John Goodman is facing more knee surgery due to his weight.

The heavy-set Roseanne star launched a bid to get slim after tipping the scale at 400 pounds (181 kilograms) in 2010 and since then he's been abiding by a healthy diet and working out at the gym on an elliptical machine to ease the strain on his knees.

He tells New York Magazine, "That's all my knees can handle anymore. I got the arthritis."

But no matter how much he exercises, Goodman, who already has one titanium knee, admits he hasn't been able to erase the effects overeating has had on his body and he is planning on undergoing a second operation on his other leg.

And the limping 60 year old accepts he only has himself to blame: "Thirty years of being a slob. I earned it."