As a child, I recall my mother reading to me often, and soon enough, when I was able to read on my own, my nose was always buried in a book. I would read on the bus to school, during recess, in between classes, and, my personal favorite, when I was begrudgingly dragged along to a baby shower once. I never really considered the correlation between being read to at an early age and my subsequent adoration of books of all kinds, but a new study done at Ohio State University speculates there’s a pretty direct link: Being read to at home in your first five years of life may be a key in predicting reading development and vocabulary later down the line.

Published in the Journal of Developmental and Behavioral Pediatrics, the study found that young children whose parents read them five books a day pre-primary school enter kindergarten having heard about 1.4 million more words than kids who were never read to. And if five books seems like a bit much, the research reveals that even kids who are read only one book a day will hear about 290,000 more words by the time they’re 5 years old, as opposed to children who aren’t normally read to.

“Kids who hear more vocabulary words are going to be better prepared to see those words in print when they enter school,” said Jessica Logan, lead author of the study and assistant professor of educational studies at the Ohio State University in a news release. “[And] they are likely to pick up reading skills more quickly and easily.”

Researchers identified the 100 most circulated books for both preschooler-targeted picture books and toddler-targeted board books. Logan and her colleagues analyzed a bunch of these and found the picture books contained around 228 words each, and board books contained about 140 words. Based on this information, they calculated how many words a child is likely to hear from birth up until their 5th birthday. They found kids who were “never” read to as children would hear 4,662 words by the time they hit kindergarten, while kids who were read to once or twice a week would hear 63,570 words, once daily would hear 296,660 words, and five books a day would amount to 1,483,300 words.

“The word gap of more than 1 million words between children raised in a literacy-rich environment and those who were never read to is striking,” said Logan.

The question of “word gaps.”

The researchers refer to this difference between well-read kindergartners and their peers as the “million-word gap.” This certainly isn’t the first time this “word gap” has been discussed, though. This conversation dates back to 1992, when a study found children from poorer families were exposed to 32 million fewer words than those from wealthier families because of differences in how often parents directly spoke or read to their children. This so-called 32-million-word gap sparked a lot of conversation and controversy, partly because the original study design was criticized as biased against families of low income and families of color.

Others, however, say the word gap is still a helpful construct for understanding differences in how children acquire knowledge and, specifically, vocabulary. “While [critics of the original study] correctly argue that we need to learn more about how children from all backgrounds learn and develop, that argument should not and must not undercut the significance of what we soundly know about child development: Young children do not profit from overheard speech about topics of interest to adults,” experts from Brookings, a nonprofit public policy organization based in Washington, D.C., wrote last year. They say that conversations born out of child-friendly topics are imperative to brain-based development.

Why reading to your kids is uniquely beneficial.  

“The words kids hear in books are going to be much more complex, difficult words than they hear just talking to their parents and others in the home,” Logan explains. For example, a kids book might introduce things like koalas, shovels, India, detectives, and other topics that likely don’t appear in your usual household conversations. “The words kids hear from books may have special importance in learning to read.”

Moreover, Logan noted the word gap found in this study is plausibly conservative because of the inevitability that parents will talk about the book being with their child or add fun and imaginative elements if the story has been heard many times. This “extra-textual” talk can expand and enrich a developing child’s vocabulary and introduce new words outside the realm of the actual story they’re being read.

Whether “word gaps” are really a thing or not, these findings suggest parents should definitely go out of their way to read to their infants and toddlers in their youngest years—it really can help them build their vocabulary earlier and make a difference in the long run.