Hemavathi, a graduate in Commerce, was found in a traumatised state when police visited the house after receiving a tip off.
She was lying on the floor looking unkempt and not even properly clothed, police said.
She was later shifted to National Institute of Mental Health and Neuro Sciences for treatment.
Looking dazed, Hemavathi told reporters she felt unbearable hunger and got food sometimes.
Rebutting the allegations that his daughter had been illegally confined, Hemavathi's father Renukappa said she had a rheumatic problem but was not taking medicines.
Her brother Somashekar said Hemavathi was not under 'house arrest' and had health problems for which she had undergone treatment.
Karnataka Health Minister U T Khader, who visited the woman, said the priority was to get her treated and restore her health.
On allegations that Hemavathi was put under "house arrest" as her parents were opposed to her marrying a person of her choice, Khader said the health department officials will look into it.
"Let her get well. We will see," the minister said.
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