Adapted from Filo/Getty
Like many epidemiologists during the COVID-19 pandemic, Katelyn Jetelina turned to social media to help keep people informed. It was the spring of 2020, and Jetelina, then at the University of Texas Health Science Center at Houston, frequently posted content on viral transmission and vaccines to her Facebook and Instagram pages. That is, until she was hacked.
In February 2021, a group of anti-vaccine activists found a way into both accounts, using her platform to post and promote a different rhetoric. They even asked her followers to upload their COVID-19 vaccination cards for a chance to win US$1,000, in a bid to gain personal information. It was at this point that Jetelina decided she had to make a change. “It was heartbreaking to me: I had lost all of my content, and all of the blood, sweat and tears I had put into it,” she recalled. “I decided to move on to a platform where I had a whole lot more ownership.”
Scientists are falling victim to deepfake AI video scams — here’s how to fight back
The most obvious choice for her was Substack, an independent writing and e-mailing platform. It’s lauded for its newsletter features — sending posts into the inboxes of subscribers — but content is also available on the site, as with a standard blog. One feature she especially liked, given her past experiences, was that her data was transferable: if you decide to leave, or have to leave, you can take a list of subscriber e-mails with you. On 8 February 2021, Jetelina started putting more energy into her Substack publication, which she calls Your Local Epidemiologist.
Although she eventually regained control of her social-media accounts, and her team still posts infographics and videos there, Jetelina says Substack enables her to connect with followers in a different way. As she explains it, the e-mail newsletter platform is more conducive to longer-form and more-nuanced discussions, which aren’t always possible on other forms of social media. Readers subscribe to her specifically, and content goes directly to their inbox, fostering more intimate and close-knit interactions. She says she’s come to know the readers well. “I can now have a two-way relationship with the audience, engaging with them through the comment and chat sections.”
Over the past few years, the newsletter has garnered a strong following and now has more than 400,000 subscribers. What was once a one-woman show is now run by a team of copy editors, social-media creators, administrative assistants and other contributors. It’s also now Jetelina’s main job, she says. And as the pandemic public-health emergency has “faded into the rear-view mirror”, her content has had to change. Jetelina now aims to show the community that public health goes beyond a pandemic and infectious diseases, and writes about topics such as reproductive health, gun violence and mental health. “I’m really trying to focus on how to equip people with the tools to live an evidence-based life,” she says.

Katelyn Jetelina did xxx.
Founded in 2017, Substack is meant to give a platform to independent writers, and provides a means for them to monetize their work through paywalls and donations. It’s grown rapidly and now has tens of millions of subscribers, and more than five million paid subscribers. The platform also raised $100 million to expand operations, giving the company a value of $1.1 billion. And it’s not exclusively for scientists: many other academics, as well as journalists and even novelists, have built up a community on the platform.
“Substack is home to a growing number of respected academics and researchers who use the platform to share evidence-based work directly with the public,” a spokesperson told Nature. “For many, it’s a way to reach people more quickly and openly, while still maintaining depth and rigour.”
Not every scientist has a following as large as that of Your Local Epidemiologist, which currently ranks number one on the list of paid science newsletters on Substacks. But other academics and scientists across various disciplines have gravitated towards the platform as a way to promote research and connect with the public.
Governments are banning kids from social media: will that protect them from harm?
Nonetheless, the site has its drawbacks. It can take a while to build a following, and making a profit can be hard work. Not only that, but many of the platform’s top science and health-politics newsletters promote anti-vaccine ideology or pseudoscience. “It’s the wild, wild west being on Substack, but right now this is the same on any sort of social-media platform,” says Jetelina. (A Substack spokesperson said that it would be inaccurate to characterize “a majority” of the top science writers as anti-vax.)
Stacking up
Substack and other subscription-based content services — such as Ghost, Mailchimp, Patreon, Beehiiv and Medium — market themselves as being more effective at reaching people than are conventional social media. This is partially backed by marketing data. According to Mailchimp, a US e-mail marketing platform, about 35% of users open e-mails from companies in the education and training sector; for other industries, the proportion is 30–40%. In a recent thread on Substack, writers shared the rates at which their subscribers opened their newsletters, and the proportions ranged from 30% to 70%.
Kimberly Nicholas, a sustainability researcher at Lund University, Sweden, whose Substack publication We Can Fix It approaches the climate crisis “with facts, feelings, and action”, says her e-mail newsletters are clicked on and opened more than her social-media posts.
The site also helps to foster an environment of community engagement. For Jonathan Tonkin, an ecologist at the University of Canterbury in New Zealand, the social-media platform X “was a really useful tool for scientists to communicate with other scientists, but in terms of reaching the public it wasn’t happening, to be honest”. Tonkin now authors a Substack publication called Predirections. “It’s good, I think, for reaching people who are interested in science and are not scientists,” he says.

Jonathan Tonkin did xxx.Credit: Prime Minister’s Science Prizes Secretariat
According to Similarweb, a traffic-analytics website, Substack’s audience is pretty evenly split between men and women. It skews a bit towards younger readers: the largest group consists of those aged 25–34. Users also tend to be based in the United States, with with about 62% of traffic coming from there in July 2025.
“Scientific subjects are nuanced, and trying to distill that into 140 characters doesn’t work very well, or leaves people confused,” adds Hannah Ritchie, a data scientist at the University of Oxford, UK. Ritchie’s Substack publication, Sustainability by Numbers, looks at potential routes to sustainability through an evidence-based lens. Putting together an e-mail, she says, “gives scientists a bit more room to describe the nuances”.

Hannah Ritchie Credit: Angela Catlin
Then there’s the potential for monetization. Most of the scientists Nature spoke to emphasized that their content is free, but the site gives writers the ability to set up paywalls. According to Jetelina, 7% of her subscribers pay for her content. Although the platform takes a cut, she’s been able to generate enough revenue to quit her full-time job and focus mainly on the newsletter. (Jetelina did not want to share her earnings with Nature, but in 2022, the monthly magazine Vanity Fair reported that she made about $300,000 in the publication’s first nine months).
Scientists also highlight that Substack offers more freedom than do other modes of publishing science — in journals, for example, or through guest contributions to online publications such The Conversation. As Ritchie explains, there’s often a lengthy editorial process in these more-formal systems, and writers can be constrained by the requirements of the publication. “The timeline is massively extended compared to what you can do on Substack, where you can have your own audience: you can say what you want, when you want to say it.”