WebMD says: Fasting on a regular basis may protect against heart disease, researchers report.
In a study of more than 4,500 men and women, people who fasted were 39% less likely to be diagnosed with coronary artery disease than those who didn't fast. Coronary artery disease was defined as having at least 70% narrowing or blockage in at least one coronary artery.
Though more than 90% of the people studied were Mormons, the findings held true even in those who had a different religious preference, says Benjamin D. Horne, PhD, director of cardiovascular and genetic epidemiology at Intermountain Medical Center in Salt Lake City.
The researchers did not put any time frame on fasting, but Horne notes that "among [Mormons], religious teachings involve fasting on the first Sunday of every month for 24 hours."
Personally, I've always kinda liked the six (or seven) fasts that Judaism has around the year. Some are particularly well timed (I'm thinking particularly of Tzom Gedalia and Ta'anit Esther) to seemingly balance out nearby holidays of heavy eating.