Kate Beckinsale has revealed she lives with a rare autoimmune disease, addressing years of public speculation about her weight. The 53-year-old actress shared a 13-part video on social media discussing her diagnosis of mast cell disease and mast cell activation syndrome, her symptoms, and her hope that opening up will help others.
Beckinsale's message to trolls
In the video, Beckinsale said: 'As I’m sure you’re aware, anytime I post a photo of myself, I receive an enormous amount of comments telling me how disgusting I look and I’m anorexic or I’m on meth or that I’ve lost so much weight.'
She continued: 'First off, I’ve lost my entire family, except my precious daughter, in a short amount of time.' Her mother, Judy Loe, died in July 2025 after a cancer diagnosis, 18 months after her stepfather Roy Battersby died in January 2024.
Living with mast cell activation syndrome
Beckinsale explained: 'I have a condition, which is an autoimmune condition called mast cell activation syndrome, and there’s another one called mast cell disease, and there’s mastocytosis.' She was diagnosed 16 years ago, crediting an 'amazing GP in London' who referred her to an expert in New Jersey.
She described her 'stomach is ground zero' for how the disease presents. She also referenced the deaths of Caroline Flack and Chadwick Boseman, and online distress from figures like Perez Hilton, saying we 'don’t know what’s going on in people’s lives.'
Beckinsale's plea for grace
She urged: 'Treat people just how you’d like to be treated yourself, give people a little grace. If you don’t have anything nice to say, maybe don’t say anything.' She added: 'You don’t want to be the last straw for somebody, you don’t want to be the thing that makes them more sick, just keep going, it’s not hard.'
In the comments, she revealed her condition was triggered by 'a horrific marriage combined with glandular fever.' She had no allergies as a child but experienced trauma.
This is not the first time Beckinsale has spoken about her health. In May 2024, she responded to weight concerns, mentioning a 'severe flare-up' of the syndrome. She said: 'What you think of my appearance and how I should look, independently of any circumstances in my life and my family is not important.'
She also noted she is 'trying to survive what feel like unbearable losses, reactivated PTSD from discovering my very young father’s almost dead body as a very young child alone in the night, and working to support the family I have left.'
Beckinsale joins other celebrities like Emilia Clarke in speaking about mast cell activation syndrome.
