Mark Harmon Tried to Keep His Disease a Secret, Now We Know

Mark Harmon Tried to Keep His Disease a Secret, Now We Know — The Truth Behind the Rumors

For years, Mark Harmon has been one of television’s most enduring stars, best known for his long-running role as Leroy Jethro Gibbs on NCIS. So when the actor quietly stepped away from the show, fans immediately began to speculate. Headlines started circulating, hinting that Harmon had been battling a serious disease behind closed doors — something he allegedly tried to keep secret.

But what do we actually know?

Despite the dramatic claims online, Mark Harmon has never publicly confirmed that he suffers from a serious or life-threatening disease. No verified statements from Harmon, his family, or his representatives support those rumors. Likewise, reputable entertainment outlets have not reported any confirmed diagnosis.

What is known is that after nearly two decades on NCIS, Harmon chose to reduce his workload. Sources close to the production have consistently pointed to the demanding filming schedule and his desire to spend more time with family as the main reasons behind his departure. Even after stepping back from his on-screen role, Harmon remained involved with the franchise in a behind-the-scenes capacity, suggesting he was still very much engaged professionally.