James Fulton's scam earned him and his wife Elizabeth a total of £50,857.58 in income support payments to which he was not entitled.
Livingston Sheriff Court was told he has been repaying the cash at £70 a month from his invalidity benefit.
But at that rate it would have to take him nearly 60 years to repay the full amount he stole from taxpayers.
Fulton, 55, of Heatherbank, Livingston, West Lothian, pleaded guilty to making false benefit claims from February 2002 until November 2010.
Sheriff Douglas Kinloch told Fulton his "health" circumstances were not exceptional enough to avoid jail and sentenced him to 16 months in prison. He said the fraud was "deliberate".