Forms of intermittent fasting exist in religious practices in various groups across the world. Religious fasting regimens include, but are not limited to, Vrata in Hinduism, Ramadan fasting (Islam), Yom Kippur fasting (Judaism), Orthodox Christian fasting, Fast Sunday (The Church of Jesus Christ of Latter-day Saints), and Buddhist fasting. Certain religious fasting practices, like Buddhist fasting, only require abstinence from certain foods, while others, like the Jewish fast on Yom Kippur, last for a short period of time and would cause negligible effects on the body. Islam is the only major religion that engages in a fasting practice reflective of intermittent fasting in terms of both 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 1.51 kilograms (3.3 lb), 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 consistent lifestyle modifications are necessary to achieve lasting weight loss." Negative effects of Ramadan fasting include increased risk of hypoglycemia in diabetics as well as inadequate levels of certain nutrients.
Dr. Michael Mosley, the creator of The Fast Diet, believes that fasting can help with weight loss. For Dr. Mosley, the term fasting does not mean abstaining from all food, but rather limiting food intake and adapting simplified eating patterns to help you lose weight. Below are some of Dr. Mosley’s recommendations for a safe fast as well as a few extra Oz-approved tips and tricks.
Fasting can take some time to get used to, as your body sheds old habits and learns new ones. But listen to your body! If you’re in hour 10 of 16 hours of fasting and feel like you absolutely need a snack, then have one. If your fasting time is up but you’re not hungry yet, wait until you are. There are no hard and fast rules here. You’re not “messing up.” You might find it helpful to jot down a sentence or two each day about how you felt; you might find that certain times of the month or year, different types of fasts work better for you.
In her blog, Gospel Taboo, Amanda Edmondson writes, "Biblically, fasting is mentioned in both the Old and New Testament. In the Old Testament it was often a way of expressing grief or a means of humbling one's self before the Lord. In Psalm 35:13, David humbled himself with fasting. In the New Testament it was a means to grow closer to God through mediating and focusing on Him. In Matthew 4:1-2, Jesus went to the wilderness to fast for 40 days. In Matthew 6:16-18 we learn that we aren’t to look somber while fasting so that it’s not obvious to others when we are fasting. Throughout the New Testament fasting and prayer are often mentioned together. In Acts 13:3, ‘they had fasted and prayed.’ In Luke 2:37 a widow worshiped day and night fasting and praying."
The ancient Greek physician Hippocrates wrote, “To eat when you are sick, is to feed your illness”. Another ancient Greek writer and historian Plutarch is also credited with penning “Instead of using medicine, better fast today”. In more recent times one of our founding fathers, Benjamin Franklin, stated, “The best of all medicines is resting and fasting”.
What makes fasting seem so novel is that, with all the diet advice out there, the easiest might be to simply not eat. Of course, fasting isn’t the same as starving yourself, which is what many people think when they hear “fasting.” And yet, fasting isn’t a diet, either. The literal definition of fasting is to abstain from food and drink from a specific period of time; it’s been around for thousands of years, as spiritual fasting is a part of many religions. But in this context, I prefer looking at fasting as simply a change in eating patterns.
Autophagy is spring cleaning for your cells. It’s Latin for “self-eating,” which is spot-on: when autophagy turns on, your cells sift through their internal parts, get rid of anything that’s damaged or old, and install shiny new versions. Autophagy is like a tune-up for your car: afterward everything runs more smoothly. It reduces inflammation and even boosts longevity. Intermittent fasting triggers, to quote researchers, “profound” autophagy, especially in your brain.
A healthy person who is not perspiring much can go without food and water for about three days before the body begins to be stressed. And a healthy person can go without food for several days if he is drinking water. Thus, the amazingly long 40-day fasts by Moses, Elijah and Jesus Christ (Deuteronomy 9:9 Deuteronomy 9:9When I was gone up into the mount to receive the tables of stone, even the tables of the covenant which the LORD made with you, then I stayed in the mount forty days and forty nights, I neither did eat bread nor drink water:
If you're looking to lose weight, this isn't a problem. And even if you're happy with your weight, this won't prove to be too much of an issue if you follow the daily fasting or weekly fasting schedules. However, if you're fasting for 24 hours per day on multiple days per week, then it's going to be very difficult to eat enough of your feast days to make up for that.
Another aspect of fasting for God is comparable to a person dedicating an action to a cause. For God and country was, at one time, a familiar declaration in the United States. It implied that the action being taken was to answer a noble call and serve a higher motive, the expectation of reward or compensation being far removed. The motivation came from a spiritual, emotional and dedicated commitment to do what is right. Similarly, a fast may be undertaken for God because it represents a lofty act, a selfless commitment to an act considered meritorious and virtuous.
In a 2017 study in Science Translational Medicine, 71 participants who completed the fasting-mimicking diet showed health benefits including weight loss, lower blood pressure and a drop in levels of the hormone IGF-1, which primarily stimulates growth but also plays a role in regulating blood glucose levels. And depending on how healthy you are, you may not need to stick to the diet too long. For instance, Longo says a healthy athlete may need to do it only twice a year, while someone who’s overweight may need to continue with it until they see the improvements they want.
A diagnostic fast refers to prolonged fasting from 8–72 hours (depending on age) conducted under observation to facilitate the investigation of a health complication, usually hypoglycemia. Many people may also fast as part of a medical procedure or a check-up, such as preceding a colonoscopy or surgery. Fasting may also be part of a religious ritual.