The Iranian human rights lawyer Nasrin Sotoudeh has ended a 49-day hunger strike in prison after Tehran's judicial authorities bowed to her demand to lift a ban on her young daughter travelling abroad.
Iran had been facing growing international pressure over her plight.
Her husband, Reza Khandan, a computer engineer, confirmed she was taking food again in a Facebook posting on Tuesday after the family had held an emotional reunion in Tehran's infamous Evin prison where an emaciated but resilient Ms Sotoudeh was allowed to hug her five-year-old son, Nima, and Mehraveh, her 13-year-old daughter.
Previously, she had been restricted to talking to them from behind a glass partition and had been denied phone contact for 19 months.
As her family looked on, Ms Sotoudeh ate her first food in seven weeks - a period of dramatic weight loss during which she drank only water mixed with salt and sugar.
Hundreds of Iranian admirers immediately responded to the news with supportive messages on Facebook and Twitter.
But Drewery Dyke, Amnesty International's Iran expert, said: "We'll only consider this a breakthrough when Iran follows its own laws and releases her."
Ms Sotoudeh, 49, is serving a six-year prison sentence after being arrested in September 2010 and convicted of spreading propaganda against the government and conspiring to harm state security.
Rights organisations around the world hail her as a prisoner of conscience whose only "crime" was to defend dissidents.
The UN, EU, Britain and the US have condemned her imprisonment and called for her release.
On the 10th day of her hunger strike, the European Parliament awarded Ms Sotoudeh its 2012 Sakharov Prize for Freedom of Thought along with Jafar Panahi, an Iranian filmmaker who is under house arrest.
The Iranian authorities repeatedly insisted that Ms Sotoudeh was being well treated and in good health. But her high-profile case has proved they are sensitive to pressure from abroad on human-rights issues.
A committee from Iran's hardline parliament said on Sunday it would visit Evin prison to assess Ms Sotoudeh's condition and would intervene if it found that her rights were not being respected.
A day earlier, the head of Tehran's cyber-police unit was sacked after the recent death in custody of a dissident blogger.
The US State Department on Friday called for Ms Sotoudeh to be released immediately, along with more than 30 other female political prisoners in Tehran. On Tuesday, the UN accused Iran of targeting the families of human-rights defenders in an attempt to curb "freedoms of expression, opinion and association".
While Ms Sotoudeh's daughter had no plans to leave Iran, the couple feared the travel ban was a sign the authorities were planning to bring charges against the girl to punish her mother.