This study investigates the risk factors for gastroesophageal reflux disease (GERD) among 9,631 adults aged 35–65 years in Iran. The prevalence of GERD was 10.99%, with higher rates among older age groups and women. After adjusting for age and sex, current smokers had a 23% higher risk of GERD compared to non-smokers, and alcohol consumption increased the odds by 1.51 times. Depressed individuals had a 46% higher risk of GERD. High intake of sweets and desserts, low intake of fiber, visceral fat, and central obesity were also significant risk factors. High physical activity levels were associated with a lower risk of GERD. The study concludes that modifying lifestyle and behavioral habits, such as improving diet, increasing physical activity, and managing weight, can help prevent and control GERD.This study investigates the risk factors for gastroesophageal reflux disease (GERD) among 9,631 adults aged 35–65 years in Iran. The prevalence of GERD was 10.99%, with higher rates among older age groups and women. After adjusting for age and sex, current smokers had a 23% higher risk of GERD compared to non-smokers, and alcohol consumption increased the odds by 1.51 times. Depressed individuals had a 46% higher risk of GERD. High intake of sweets and desserts, low intake of fiber, visceral fat, and central obesity were also significant risk factors. High physical activity levels were associated with a lower risk of GERD. The study concludes that modifying lifestyle and behavioral habits, such as improving diet, increasing physical activity, and managing weight, can help prevent and control GERD.