Jett Travolta died in 2009 after a seizure caused him to hit his head in a bathtub in the family's holiday home in the Bahamas.
Both Kelly and husband John Travolta have previously remained private about the tragedy.
Speaking on an episode of The Doctors due to air on November 21 in the US, Kelly speaks at length about her son's condition and the effects it had on their family.
"[Jett] was autistic. He had seizures and when he was very young, he had Kawasaki syndrome," Kelly explains.
"I strongly believe as a mother, as does my husband, that there are certain contributing factors that lead to autism and some of it is very much the chemicals in our environment and in our food," she added.
Kelly hopes to highlight how an organic, chemical-free lifestyle can help other families living with autism.
Since Jett's passing, John and Kelly have had welcomed another son, Benjamin, now two years old.