The association between adult penile length and IQ: evidences from 139 countries

Abstract

Abstract Objective This study investigates the global correlation between adult penile length and Intelligence Quotient (IQ).Methodology: The study utilizes data from 115,387 males aged 18–65 across 139 countries, examining penile size and IQ measurements. After adjusting for variables including GDP per capita, educational spending, daily maximum temperature, and BMI, we performed partial correlation and regression analyses on penile length and IQ, along with an interethnic comparison.Results A statistically significant negative correlation was found between flaccid penile length and IQ (P < 0.001), indicating higher IQs in individuals with shorter penile lengths, and notable ethnic differences were observed (P < 0.001).Conclusions The inverse relationship between flaccid penile length and IQ could be linked to genetic, evolutionary, or environmental factors, offering insights into the penile size-IQ connection.