CHICAGO (CBS) — Anxiety, anger, or unexplained aches and pains are all signs of depression. An estimated 16 million adults in the U.S. suffer from some type of depression.

Olympian Michael Phelps was among more than 50 speakers who took the stage Tuesday at The Kennedy Forum Annual Meeting, hoping to end some of the stigma surrounding mental illness.

RELATED: For Phelps, Helping Others With Depression ‘Light Years Better’ Than Olympic Gold

The most decorated Olympian in history was one of six honorees at the annual summit on depression and brain-related illness.The 23-time gold medalist has struggled with depression, and has been pushing to change the way mental illness is looked at and treated in the U.S. and around the world.

Other honorees include Former Obama political strategist David Axelrod, Cook County Sheriff Tom Dart, Illinois Supreme Court Justice Anne Burke, and New York City first lady Chirlane McCray. Other speakers include Chicago rapper Common, former Dallas Police Chief David Brown, and actor Tom Arnold.

Prominent Chicago businessman Peter O’Brien said his son once had a life full of promise.

“He was six-foot-three, he had a jaw like a rock. He loved sports. He was a great student without even trying,” O’Brien said.

But in his late teens, Peter O’Brien Junior displayed behavior that alarmed his parents.

“It was about when he was 20-years old he was diagnosed with schizophrenia,” O’Brien said.

Peter Junior’s parents provided the best care, but it wasn’t enough.

“He didn’t want to admit he had a mental illness, because ‘Dad no one respects those with mental illness,'” O’Brien said. “Because he self-medicated with alcohol, Peter succumbed to a burst pancreas and died at 32-years old.”

Mental health care is Peter O’Brien’s passion and led him to Patrick Kennedy, member of the legendary political family, whose own mental illness inspired him to create the the Kennedy Forum now meeting in Chicago.

The Kennedy Forum was founded five years ago by former U.S. Rep. Patrick Kennedy, who left Congress in order to focus on issues involving brain diseases like mental health and addiction. He said we are in a race for inner space, and the forum is meant to set a new standard for the future of health care in the United States.

“The message to the people is there is no stigma in seeking help,” Kennedy said.

Kennedy has an ally in swimmer Michael Phelps, the Olympic champion, who wants people to learn from his experiences with depression.

“To be able to save a life and to help somebody grow from experiences they’ve had like I’ve been able to do that’s way bigger than anything I’ve accomplished in the world of swimming,” Phelps said.

Chicago’s own Common, whose foundation is addressing the city’s violence, said mental health care has to be part of the prescription.

“Some of the people who end up in prison, if they were treated with mental health care, would not have ended up in prison. Lives wouldn’t have been lost,” Common said.

Ryan Keesling, founder of Free Write Arts & Literacy, said the right to affordable healthcare that treats the whole body, brain, and spirit is essential. That way mental health patients can experience proper treatment, rather than the criminal justice system, which is so often the case.

Free Write works with incarcerated and court-involved youths to develop literacy, creative writing, music, and other artistic skills.

“A lot of young people who we meet in the detention center come in not really knowing that they had the skills that they have. So they come in and improve their literacy, they come in and improve their artistic skills; but they also discover that they have community-building skills, leadership skills, activism skills, in addition to the artistic skills that they cultivate. So that’s always fun to watch,” he said.

Peter O’Brien said he hopes in honoring his son’s memory lives will be saved.

“It’s my hope that Peter’s life will not be in vain, that’ll there will be others that will get help that they need,” O’Brien said.

Since the creation of the Kennedy Forum, Peter O’Brien said he rarely goes anywhere without someone mentioning a family member’s mental illness or their own struggles.

The Kennedy Forum’s annual meeting was being held Tuesday from 7 a.m. to 7 p.m. at the Hilton Chicago Hotel.