'There's a sense that these algorithms are objective and they get to know you': How social media warps our understanding of healthcare

Social media has upended how people engage with healthcare, as it provides a platform for people to share their experiences, find support groups, and learn more about symptoms and conditions.

But it's also given nefarious actors a platform to promote products, spread misinformation and prey on people's fears.

Meanwhile, algorithms deliver users an individually tailored stream of content, promoting and prioritizing the most engaging posts with little oversight.

In her book " Bad Influence: How the Internet Hijacked Our Health " (Oneworld Publications, 2026), author Dr.

Deborah Cohen , a broadcaster, journalist and editor who has a medical degree from the University of Manchester in the U.K., examines how social media platforms and influencers have transformed people's views of healthcare, from the proliferation of weight-loss drugs and hormone therapies to billionaires seeking immortality.

Cohen spoke with Live Science about her book, the shifting landscape of healthcare discussions moving online, and how health literacy is now key.

"Bad Influence" has been short-listed for the 2026 Royal Society Trivedi Science Book Prize .

Read an excerpt: 'A fine line between reducing stigma and trivialising conditions': Social media, self-diagnosis and the glamorization of ADHD Hannah Osborne: You wrote in the book that we're in the middle of a global experiment in public health that will take years to understand.

What do you think the results are going to be? Deborah Cohen: What we know about healthcare is our ideas, concerns and expectations shape health.

So if you go to a doctor, what they're trying to establish is what your ideas might be about your particular condition, your concerns and what you want to take away from that particular consultation.

Obviously, our ideas and concerns or expectations are very much shaped by the information environment, and this is going to change again when we're adding large language models [LLMs] into the mix.

We're going to have a new wave of health literacy.

My concern from writing the book is there's possibly a lack of understanding of what healthcare can always deliver.

One of the challenges I felt was when you go to social media and it provides you with certainty and often quick fixes, but then you go to the Health Service [the National Health Service (NHS), the U.K.'s health system], where they can't really provide you with certainty, and there's complex solutions or there isn't an obvious solution.