do jains fast?
They fast particularly during festivals and it is  practiced according to one's ability.
Food and fasting
Jains fast particularly during festivals. This practice is called "upavasa", "tapasya" or "vrata", and may be practiced according to one's ability.
which of the following is not among the practices of jainism Violence, attachment, sensual pleasures, lie and possessiveness are some of them. and which are the practices? Jains take five main vows: “ahiṃsā”, “satya”, “asteya”, “brahmacharya” and “aparigraha". when did jainism begin? Historians date it to 8th or 7th century BCE. who is the leader? Rishabhanatha what are the beliefs? It is transtheistic and forecasts that the universe evolves without violating the law of substance dualism, auto executed through the middle ground between the principles of parallelism and interactionism.
Yes, Jains fast particularly during festivals. Yes Yes, they fast particularly during festivals.
Jainism Jainism Jainism
Food and fasting Food and fasting Food and fasting
Jains fast particularly during festivals. Jains fast particularly during festivals. This practice is called "upavasa", "tapasya" or "vrata", and may be practiced according to one's ability. Digambaras fast for "Dasa-laksana-parvan", eating only one or two meals per day, drinking only boiled water for ten days, or fasting completely on the first and last days of the festival, mimicking the practices of a Jain mendicant for the period. Śvētāmbara Jains do similarly in the eight day "paryusana" with "samvatsari-pratikramana". The practice is believed to remove karma from one's soul and provides merit ("punya"). A "one day" fast lasts about 36 hours, starting at sunset before the day of the fast and ending 48 minutes after sunrise the day after. Among laypeople, fasting is more commonly observed by women, as it shows her piety and religious purity, gains merit earning and helps ensure future well-being for her family. Some religious fasts are observed in a social and supportive female group. Long fasts are celebrated by friends an Jains fast particularly during festivals. This practice is called "upavasa", "tapasya" or "vrata", and may be practiced according to one's ability. 
wiki:7671786
Jainism [SEP] Food and fasting
"Digambara" monks observe a stricter vow by eating only once a day. Jains fast particularly during festivals. This practice is called "upavasa", "tapasya" or "vrata", and may be practiced according to one's ability. Digambaras fast for "Dasa-laksana-parvan", eating only one or two meals per day, drinking only boiled water for ten days, or fasting completely on the first and last days of the festival, mimicking the practices of a Jain mendicant for the period. Śvētāmbara Jains do similarly in the eight day "paryusana" with "samvatsari-pratikramana". The practice is believed to remove karma from one's soul and provides merit ("punya"). A "one day" fast lasts about 36 hours, starting at sunset before the day of the fast and ending 48 minutes after sunrise the day after.