Coffee stunts your growth
No scientific evidence supports the claim that coffee or caffeine stunts height growth in children or adolescents. The myth likely originated from early, overstated concerns about caffeine reducing calcium absorption, an effect that later research found to be minor and easily offset by normal dietary calcium intake.
What we know
The belief that coffee stunts growth traces back to older research on caffeine's effect on calcium metabolism. Some studies from the mid-to-late 20th century found that caffeine modestly increases urinary calcium excretion, and this observation was extrapolated into the assumption that caffeine consumption during childhood or adolescence could impair bone mineralization and, by extension, limit height. Over time this speculative chain of reasoning hardened into the folk belief that a child who drinks coffee will end up shorter than they otherwise would have been.
Subsequent research has not supported this extrapolation. Harvard Health has stated directly that there is "no scientifically valid evidence to suggest that coffee can stunt a person's growth." The calcium-excretion effect that originally sparked the concern turns out to be small in magnitude, roughly equivalent to the calcium found in a few tablespoons of milk, and is easily compensated for by typical calcium intake from dairy, fortified foods, or supplements in a normal diet. Several of the early observational studies linking coffee drinking to shorter stature in children also suffered from a confounding problem: children who drank more coffee often drank correspondingly less milk and other calcium-rich beverages, meaning the apparent association may have reflected reduced calcium intake overall rather than any direct suppressive effect of caffeine on bone growth.
Height itself is overwhelmingly determined by genetics, contributing an estimated 60 to 80 percent of the variation in adult height within a population, with the remainder influenced by overall childhood nutrition, chronic illness, hormonal factors such as growth hormone and thyroid function, and sleep quality during the growth years. Caffeine has no established mechanism of action on growth hormone secretion, on the growth plates (epiphyseal plates) at the ends of long bones, or on the cellular processes of bone elongation at the doses typically consumed by children or teenagers who drink coffee, tea, or caffeinated soft drinks.
That said, public health guidance does not give caffeine a clean bill of health for young people, just not for the reason commonly assumed. The American Academy of Pediatrics and similar bodies caution against caffeine consumption in children and adolescents because of its effects on sleep quality and duration, its mild cardiovascular stimulant properties (increased heart rate and blood pressure), and its potential to contribute to anxiety or dependence with regular heavy use. Sleep is itself important for growth, since growth hormone is released in pulses predominantly during deep sleep stages, so if caffeine meaningfully disrupts a child's sleep, an indirect and modest effect on growth could theoretically occur, mediated through sleep disruption rather than any direct action of caffeine on bone or hormonal pathways.
A 2020 review in the International Journal of Environmental Research and Public Health examining caffeine consumption in children reached a similar conclusion, characterizing existing concerns about caffeine and growth as unsupported by the modern evidence base while still flagging sleep displacement and cardiovascular stimulation as the more legitimate considerations for pediatric caffeine intake. The persistence of the growth myth, despite this evidence, likely reflects how intuitively appealing simple cause-and-effect stories are compared to the more complicated reality involving confounded observational data and small, compensable physiological effects.
Common claims
- Drinking coffee as a child or teen stunts height growth.Not supported
- Caffeine reduces calcium absorption enough to affect bones.Partly accurate
- Height is mostly determined by genetics.Accurate
- Caffeine has no health considerations for children at all.Not supported
Evidence hierarchy
All sources
- Does coffee stunt your growth?Harvard Health Publishing · 2021
- Caffeine consumption and health effects in childrenInternational Journal of Environmental Research and Public Health · 2020
- Caffeine and childrenAmerican Academy of Pediatrics / HealthyChildren.org · 2022
- Growth and geneticsNemours KidsHealth · 2021