Stephanie Buttermore Cause of Death: Fitness Influencer Dies Suddenly at 36, No Official Cause Disclosed
The fitness and science community is in mourning following the sudden death of Stephanie Buttermore on March 6, 2026. The 36-year-old fitness influencer, YouTuber, and ovarian cancer researcher died just nine days after celebrating her birthday on February 25. As of Monday, March 9, the Stephanie Buttermore cause of death has not been officially disclosed.
Stephanie Buttermore Cause of Death: Family Requests Privacy, No Details Released
Jeff Nippard's team announced the tragic news on Instagram, stating the death was sudden but not disclosing the cause. The statement appealed to the online community to respect their privacy during their moment of grief.
The announcement read: "It is with profound sorrow that we share the sudden passing of Jeff's fiancée and partner of ten years, Stephanie. She will be remembered for her warmth and compassion, her love for her family, and her PhD research on ovarian cancer. We kindly ask for privacy as we navigate this tragic loss."
Her death came as a particular shock because Nippard had posted a Valentine's Day photo of the two sitting together on a couch just two weeks earlier, with Buttermore appearing healthy and smiling brightly.
Who Was Stephanie Buttermore: PhD Researcher and Body Positivity Pioneer
Before her death, Buttermore held a PhD in Pathology and Cell Biology from the University of South Florida. Like her fiancé, she was a YouTube fitness influencer who also focused on ovarian cancer research.
Her area of research focused on ovarian cancer detection and early screening, where she succeeded in discovering a protein called RHAMM — a protein that could potentially be used as an early screening marker for the disease through a urine test.
Buttermore gained wider prominence during her "All In" challenge, where she consumed upward of 10,000 calories per day to promote healthy weight gain for women and body positivity, resonating with millions of followers who struggled with disordered eating.
Stephanie Buttermore's Final Instagram Post and Social Media Absence
Buttermore stepped back from social media throughout 2024, citing dramatic improvements to her mental health as a result. In her final Instagram post in May 2024, she wrote that she no longer struggled with anxiety at all — something that had once been almost crippling, to the point where she felt she could not breathe or leave her house.
She added that she felt far more present in everyday life once she stepped away from the platform — more immersed in moments with family and Jeff, no longer distracted by comments or notifications. She described family time as simply family time, with no asterisks.
Her final known public moment came on Valentine's Day 2026, when she commented on Nippard's post with the words "Love you forever" — a message that would unknowingly become her last public communication to her fiancé and her online community.
Jeff Nippard and Stephanie Buttermore: A Decade-Long Love Story
Nippard and Buttermore were partners for ten years and got engaged in October 2022. Their relationship began after Nippard slid into Buttermore's DMs, with the two immediately forming a deep friendship and Skyping for three to four hours every day before he traveled from Canada to visit her in Florida.
Nippard's Instagram and YouTube accounts shut off comments on posts announcing Buttermore's death, but fans flooded the Valentine's Day post with condolences. Fellow influencer Buff Bunny wrote that heaven had gained an amazing angel and someone who cared so deeply for others.
Buttermore had garnered over 525,000 followers on Instagram and more than 1.17 million subscribers on YouTube at the time of her death. The Stephanie Buttermore cause of death remains unknown as her family and Jeff Nippard continue to grieve privately.
