Once one of the brightest stars in the National Football League, Favre played 20 seasons in the NFL and spent most of his career with the Green Bay Packers, with whom he won the Super Bowl in 1997.
Favre said at the hearing on welfare accountability that he lost his investment in a company he believed was developing a breakthrough concussion drug.
"While it's too late for me - because I've recently been diagnosed with Parkinson's - this is also a cause dear to my heart," he said.
The 11-time Pro Bowler previously said that he believed he suffered potentially thousands of concussions during his football career. Favre, who has two daughters, said that if he had a son he would discourage him from playing the sport.
Beginning in 2011, thousands of former players sued the NFL claiming ongoing debilitating effects from head injuries. The league later settled for an estimated $1 billion and overhauled its concussion protocols, while outlawing some of the game's more violent hits.
Favre appeared at the US House panel after he became one of several defendants named in a civil suit by Mississippi’s Department of Human Services in 2022.
The suit alleged the misuse of welfare funds earmarked for the state's neediest families, known as TANF funds. He has never been accused of crimes related to the funds and he said on Tuesday that he was innocent of wrongdoing.
"Certain government officials in Mississippi failed to protect federal TANF funds from fraud and abuse and are unjustifiably trying to blame me," said Favre.
"Those challenges have hurt my good name and are worse than anything I've faced in football."