ADHD and the Use of Sans Fonts: Do They Make a Real Impact on the Legibility?

I’ve got a question for you: while studying or working, have you ever noticed that sometimes it’s easier or more difficult to read, but you don’t know why?
Have you ever opened a webpage or a book and felt, “I can’t read this,” even though you were really interested in it?

I have — and I’ve found that our inability to focus on something we need and want to read could be related to the type of font used in the text. In my case, it actually is.

Check out these two screenshots and see which one seems more compelling to you, more soothing to your eyes:

(Click to enlarge)

Did you feel a difference?

What Matters in the Legibility of a Text?

In any given copy, what matters the most is basically:

• the type of font (for instance, Times New Roman is a “serif” font, while Arial is a “sans” font),
• the line height (the space between lines in a paragraph), and
• the color (the contrast between the text and its background).

For the purpose of what I’ll be sharing with you, we’re going to assume that a text has a nice line height and color contrast, and we’re going to focus on the difference in the type of fonts.

The Difference Between Serif Fonts and Sans Serif Fonts

Among the different types of fonts ^[1], the two most commonly used are the serif fonts and the sans serif fonts.
The main difference between them is the small lines attached—or not—to the letters: serif fonts have these lines, while sans fonts don’t.

Serif fonts give us a sense of professionalism—an old-school kind of writing—while sans fonts look more informal, but also clearer.
We could go deeper to discover more differences ^[2], but our eyes don’t lie. Here’s a list I made of my favorite fonts:

Learning How to Write and Read

I began noticing the difference between those fonts when I was in Law School. Presenting our papers in Times New Roman was mandatory and, for some reason, there was something about it that bothered me. Eventually, I tried writing in Arial and felt something like, “Wow, now I can see.”

I’m going to take you a little bit back in time so we can understand where this difference comes from and why it matters.

From Block Letters to the Cursive Style

When we’re children, we begin learning to write with block letters—which is no surprise: we learn the letters of the alphabet one by one, and then we start putting them next to each other to create words. Eventually, teachers make us move on to the cursive style because “it looks more professional and that’s how adults do it.” ^[3]

I switched from pencil to pen, and from block letters to cursive style, during my first year of primary school. I remember many of my classmates (if not most of them) struggled a lot with the change, but I didn’t. Calligraphy class was “art” for me; I wanted to be a writer, and that was my pass. I simply loved it.

I also believe—when it comes to my ADHD—that the change wasn’t difficult for two more reasons:

• one, the high-protein diet we need is basically the daily diet in Argentina (where I grew up);
• two, my need to drain hyperactivity so I could focus was also being taken care of. I was outside climbing trees and running all day long, and I started doing sports at seven.

From Analog to the Screen

I loved writing in cursive, but it was hard to read from it. So when I got to college and had the freedom to take notes however I liked, I started writing with block letters again and left the ink for the sinful Bic rollerball pen (I went to a private Catholic school; using a rollerball pen was a ticket to the confessional).

But later, technology arrived. We had to start typing our papers on computers using the mandatory Times New Roman font. During the late ’90s, it was “trendy” when trendy wasn’t even a word—and I simply didn’t like it. It didn’t feel like my own writing.

Somehow, at some point, I typed my notes using the Arial font… and it felt different. I printed them and studied from them, and—as I said—I felt I could finally see. The text looked so clear, as if I didn’t even need to pay full attention to what I was reading because the keywords just popped out from the text. So, I stuck to it.

What’s Out There: Designing for ADHD

When I started writing again and opened my blog, I used the Adobe Carlson font (a serif font). That’s the one The New Yorker—one of my favorite magazines—uses, and I love it. In fact, serif fonts are so beautiful that most websites with serious writing, so to speak, use them.

But then, after publishing my second post one day I tried to read it and couldn’t get to the second paragraph—of my own post! And so that old thought came to mind: “Arial’s clarity,” and the question, “Could the font style be messing with my legibility?”

Besides Poole (2020), who wrote about the legibility of serif and sans serif fonts ^[2], I believe McKnight (2010) is worth reading. In Designing for ADHD: In Search of Guidelines, she mentions the use of “large print (12–14 point) and clear sans-serif fonts such as Arial.” ^[4]

I went over the bibliography she used, dug a little more, and found that this idea comes from guidelines used to print children’s books. Sans fonts are clear for children, and that’s why designers use them. The literature on that is quite abundant, but when it comes to legibility for neurodivergents (with ADHD in this case), there’s a huge void.

My ADHD and the Rounded Fonts

After reading the first study, I didn’t think twice. I downloaded the Open Sans font (by Google) and installed it on every single software I use—and I saw the light. A whole paragraph was suddenly clear as water, making it easier for me to pick out keywords.

Still, it was a big change for me. At first, I even felt I wasn’t writing “something worthy of a writer,” but then… look at me posting!

Later, I paid a visit to my psychiatrist—who has ADHD too—and without giving him a hint, I started asking about his experience in Med School. I believe the first thing he said was, “I hated Times New Roman!”

My ADHD gut never lied to me (it’s one of our superpowers!). So, before I procrastinate and jump into writing a thesis, I’ll leave my humble hypothesis here:

“The use of sans fonts improves legibility for people with ADHD.”

Improving the Legibility for People With ADHD

As I said at the beginning, many factors influence the legibility of a text besides its font—such as line height and color contrast. Furthermore, when we visit websites with pop-ups, inconsistent color palettes, or when we read PDF files filled with huge logos and images, all that really gets in the way of our attention.

The world has changed, and we don’t know if or when things will be as they were. Now we find ourselves living in front of screens and teaching our children through digital devices—when the ADHD brain craves the analog.

Thus, if the use of sans serif fonts influences legibility for people with ADHD, this could have a huge impact on our lives. Just by changing the fonts I use, my quality of life changed. I’m a writer; all I do is read and write—and now I can do it effortlessly.

I humbly believe that now, more than ever, this should at least be a topic worth discussing.

If you’ve read something or know better than I do, or if you think you could help with this research (by defining variables, etc.), please enlighten me in the comments or contact me.

If you’d like to try the fonts on your computer, check out how to install them from my Blogging Toolkit.

Footnotes and References

1. Adobe classifies fonts into eight (8) categories, and Google into five (5).
2. Poole, Axel. Which Are More Legible: Serif or Sans Serif Typefaces? [Last visited: May 2020].
3. Rueb, Emily (2019). Cursive Seemed to Go the Way of Quills and Parchment. Now It’s Coming Back. The New York Times. URL: https://www.nytimes.com/2019/04/13/education/cursive-writing.html [Last visited: May 2020].
4. McKnight, Lorna (2010). Designing for ADHD: In Search of Guidelines. URL: http://homepage.divms.uiowa.edu/~hourcade/idc2010-myw/mcknight.pdf [Last visited: May 2020].