According to Islamic Hijra calendar in Islam, Ramadan is the ninth lunar holiest month. During that time Muslims do not eat and drink from sunrise to sunset. Fasting during the holy month of Ramadan is mandatory for all healthy adult Muslims and it is regarded as an Act of devotion which brings great blessings to health. The present study was a cross-section observation to understand the impact of Ramadan fasting on Body Mass Index (BMI) among the Muslim adults of north 24 Parganas district in West Bengal, India. Data were collected from 124 females and 40 males on height, weight and food habits during the fasting period. All the parameters were recorded four times i.e. the first week, mid-week, last week and one week after the Ramadan period to observe the change in BMI. The results revealed that there was an insignificant change in BMI and weight between periods of Ramadan fasting. The decreasing trend in weight was observed from the start to the end of the Ramadan fasting period. Overall, the changes in BMI and weight were not so much but the study participants practised healthy diets during these cultural events, which may an example of maintaining healthy food habits during the life course.