Mr Tohti, an economics professor who has criticised China's ethnic policies, has been detained since January. He has been charged with separatism.
His lawyer Li Fangping met with him for the first time this week.
He said Mr Tohti was denied food for 10 days after an attack on a Kunming train station in March that killed 29 people.
The attack was blamed on Uighur separatists by the Chinese authorities.
Mr Tohti is a member of the predominantly Muslim Uighur ethnic group from China's far western Xinjiang region.
He has been critical of China's treatment of the Uighurs but there is no record of Mr Tohti ever having supported the cause of separatism, says the BBC's John Sudworth.
Mr Tohti maintains his innocence, said his lawyer.
"He believes that in his words and deeds, he has always sought to work for the country's national interests and the organic integration of the Han majority and Uighur minority's common benefits," said Mr Li.
He added that Mr Tohti went on a hunger strike in January for 10 days to protest against being served food that did not follow Islamic dietary laws.
Authorities force-fed him milk when his organs started bleeding, his lawyer was quoted by news agencies as saying.
China has blamed a number of violent attacks on civilian targets over the past year on Uighur separatists and launched a sweeping security crackdown.
Earlier this month it executed 13 people for what it said were terrorism-related offences.
It has recently carried out at least two mass-sentencing events in front of large crowds gathered in sports stadiums.
The detained Uighur academic Ilham Tohti was denied food for more than a week and his legs have been shackled, his lawyer says.