This study explores the impact of observing Ramadan intermittent fasting (RIF) on body weight in Turkish residents, marking it as the first study conducted in Turkey to investigate the interplay of religious fasting with dietary changes amid the COVID-19 pandemic. We hypothesized that observing Ramadan fasting would result in weight loss attributable to dietary changes, while decreased physical activity would correlate with weight gain during this period. A cross-sectional survey was conducted among Muslims aged 18+ in Turkey who fasted at least two days during Ramadan 2021. Data were collected via Google Forms, with 1669 participants recruited through social media. Descriptive statistics summarized participant characteristics, and Pearson's Chi-square tests assessed weight change differences. Binary logistic regression identified predictors of weight gain, adjusting for factors such as sex, age, physical activity, water consumption, and diet. Of the 1669 respondents (53.6% female), 49.4% perceived their weight as normal, while 47.0% classified themselves as overweight or obese. Logistic regression indicated that decreased physical activity (AOR = 1.618, =0.001) and increased fat intake (AOR = 1.9, 95% CI 1.2-2.9) were significant predictors of weight gain. Our findings emphasize the importance of promoting healthy eating and regular physical activity during Ramadan.