Fasting, like prayer, is an act of worship and the fourth pillar of Islam. It is compulsory for all Muslims, both men and women, but pregnant women, the sick, and travellers are exempted from fasting. Travellers have to observe fasting after the end of their journey, pregnant women after the delivery of their child, and the sick when they become well. Women during menstruation need not fast but have to make up the lost days afterwards.
Allah says in the Qur’an:” O you who believe! Fasting is prescribed to you as it was prescribed to those before you, that you may (learn) self-restraint.” (Al-Baqarah:183)
Islam requires of the Muslim, first and foremost, that he be a true and sincere believer in Allah, closely connected to Him, constantly remembering Him, and putting his trust in Him while trying to help himself. The Muslim should feel in the depths of his soul that he is in constant need of Allah's help and support, no matter how much he may think he can do for himself.