Even 1 minute of screen time harmful for children under 2, study warns

Exposing infants and toddlers under 2 to smartphones or tablets — even for educational content — can negatively affect their language and emotional development, a new study has found. The researchers said screen exposure during early life should be kept as close to zero as possible.

The findings come from a research team called iADDICT, drawn from four British universities — the University of Leeds, Leeds Trinity University, Aston University and Loughborough University — who conducted a meta-analysis of 48 studies published since 2020. The report was commissioned by the child welfare organization 1001 Critical Days Foundation.

The researchers described the period from birth to age 2 as a "golden window" for brain and language development. Their analysis found that for every additional minute a child in this age group spent looking at a smartphone or tablet, the number of vocalizations the child made fell by an average of 4.9, while the number of words a parent directed at the child dropped by 6.6. Children around age 2 who were exposed to smart devices for an average of about 1.5 hours a day were more likely to score below average on assessments of language and cognitive ability.

Screen exposure also affected broader development. Infants repeatedly exposed to smart devices before 6 months of age were roughly three times more likely to fall into a high-risk group for autism spectrum disorder than those who were not, the research team found. The researchers attributed this to the cognitive burden that intense visual stimulation places on the brain, as well as the reduction in time available for real-world play and interaction.

Negative effects on diet and physical health were also identified. Children who habitually used smart devices during meals faced a higher risk of childhood obesity, and reduced physical activity was linked to a greater likelihood of developing chronic constipation around age 3.

Sleep and eyesight were also affected. Blue light and sustained visual stimulation from screens can disrupt deep sleep and increase nighttime waking, the research team said. Repeated exposure to smart devices within the first year of life may also interfere with eye development, raising the risk of severe myopia or astigmatism before school age.

"Parents should not allow even a single minute of intentional screen exposure for infants — whether for learning, communication or entertainment," the research team warned. They added that screens should be removed entirely from the presence of children under 2, and that more time should be devoted to toy play, outdoor activity and ongoing verbal interaction with parents in order to protect developing brains.

Experts say that during infancy and early childhood, direct human interaction — eye contact, conversation and physical play with parents — plays a far more important role in brain development than any digital device. While smart devices can serve as a temporary aid in child-rearing, they cannot substitute for the language and emotional development that occurs in early life, making it important to minimize screen exposure as much as possible.