A man weighing 33 stone (210kg) who was taken to a psychiatric hospital against his will says he plans to sue the social services department involved.
Chris Leppard's condition affects one in 15,000 people
Chris Leppard, 23, from Hastings, East Sussex suffers from Prader-Willi syndrome, an inherited condition which drives him to over eat.
He was taken to the Eastbourne Clinic last week, but returned home on Monday evening after being assessed.
Mr Leppard said the ordeal hampered the
progress he was making losing weight.
"I am going to take social services to court for what they have done because I am not mentally ill and I have my own independent life," he said.
Mr Leppard said he now planned to return to his controlled diet to prove to the authorities he can lose weight without enforced care.
His mother Anne said she was upset by the disruption caused to her son's routine.
"Instead of going to these drastic measures, they could have put the money into getting the right support for my son.
Health and safety
"I am really upset because before this I had managed to get his confidence up after six years to fight this illness, but this has caused a real hiccup," she said.
Mrs Leppard said she had written a letter of complaint to East Sussex social services and had consulted a solicitor about the possibility of legal action.
East Sussex County Council said all proper procedures were followed and such orders were "in the interest of that person's health and safety or to protect other people".
"We have worked closely with Chris and his family for three years and will continue to offer our support," the council said.
Jackie Waters, from the Prader-Willi Syndrome Association, said: "In extreme cases patients with the condition do have to be taken into care for their own protection. But it is only advised as a last resort."
There is no cure for Prader-Willi syndrome, which affects one in 15,000 people.
For someone to be sectioned under the Mental Health Act doctors and an approved social worker have to approve the measure.