Nineteen-Day Fast to be the one foretold by the Báb, accepted the fast, but altered many of its details and regulations. The Bahá'í fast resembles fasting practices of several other religions. Lent is a period of fasting for Christians, Yom Kippur and many other holidays for Jews, and the fast of Ramadan is practiced by Muslims. The Bahá'í fasting most resembles the fast of Ramadan, except that the period of fasting is defined as a fixed Bahá'í month, whereas Muslims fast during a lunar month, whose specific Gregorian dates vary from year to year. Bahá'u'lláh established the guidelines of the fast in
Intermittent fasting food consumption and diet consistency. The duration of the Ramadan fast is between 28 and 30 days, depending on the year, and consists of not eating or drinking from sunrise until sunset. During the holiday, Muslims eat twice per day: once in the morning before dawn and once in the evening after dusk. A meta-analysis on the health of Muslims during Ramadan shows significant weight loss during the fasting period of up to , but this weight was regained within about two weeks of Ramadan ending. The analysis concluded that "Ramadan provides an opportunity to lose weight, but structured and