The duchess gave a speech at the launch of the "Taking Action on Addiction" campaign by the Forward Trust, a British charity of which she is a patron, about the reality of addiction as a "serious mental health condition."
"Addiction is not a choice. No one chooses to become an addict," she said. "But it can happen to any one of us. None of us are immune."
Kate, wife of Prince William, stressed that despite addiction's omnipresence, it is "seldom discussed" as a serious mental health condition in society.
She added that it is crucial to recognize "what lies beneath addiction" so "we can help remove the taboo and shame that sadly surrounds it."
The duchess was joined by popular UK television presenters Ant McPartlin and Declan Donnelly in launching the campaign, which strives to "reframe existing perceptions of addiction and build awareness of the causes and nature of addiction."
She highlighted the toll the pandemic has taken on families and children hit by addiction issues.
"We know that over one and a half million people across the UK who did not have substance misuse prior to lockdown may now be experiencing problems associated with increased alcohol consumption," she said.
The duchess also pointed toward an alarming increase of one million young people exhibiting addictive behavior since the pandemic began.
Around two million people who would have been classified as "in recovery" may have suffered a relapse over the past 18 months, she said.
Despite the stark figures, she paid tribute to the likes of the Forward Trust, which, she said are helping people to turn their lives around.
The campaign will "show us that, not only do many people recover from addiction, but they can also go on to prosper," she emphasized.
On Sunday, Kate and William attended the awards ceremony for the inaugural winners of the Earthshot Prize -- a Nobel-like award for the environment founded by the duke and renowned British naturalist David Attenborough to inspire innovative solutions to the most pressing environmental challenges facing the planet.