Intermittent fasting is gaining popularity due to the wide variety of ways one can practice this diet based on a person’s ease and preference. It provides a regular interval of feasting, so unlike other diet programs that restrict individuals to a prescribed regimen over a prolonged period, it is more comfortable and natural to pursue. Also, the diet intervals are not too long to create the type of cravings that force dieters to indulge in binge eating once the fast cycle is over, resulting in regain.
Time-Restricted Fasting (Leangains Method)
It is also called the 16:8 method. This method involves 16 hours of fasting with 8 hours of feeding window. For women, the recommended fasting period is 14 hours. A person can take two to three meals during the feeding window. Preferable fasting period for most people is from the evening till next noon. This preference has no medical significance and is chosen purely on behavioral and social reasons. It is considered more comfortable to stay hungry during this window as a fasting individual spends more time sleeping while many people don’t feel hungry in the early part of the day and prefer to go to bed satiated. Those who are used to having a good breakfast might struggle with this method. Scientifically a study on mice has shown a positive impact on weight loss for mice feeding for only 8 hours despite taking as many calories as mice feeding for the whole day. Another version of this method recommends keeping the feeding window in the morning while restricting it from the afternoon till the next day. The argument for this method is that skipping breakfast results in less efficient regulation of insulin after lunch. There is a naturally enhanced ability to regulate blood glucose in the morning, so taking a proper breakfast but staying hungry after lunch and through dinner has a positive effect on insulin sensitivity.
5:2 Diet:
Among the practitioners of this method, one of the prominent names is British journalist Michael Mosley. In this method, one can restrict calorie intake to 500-600 calories for two days each week while regularly eating for the rest of the week. For women, preferable intake is 500 calories. Ideally, on the fasting days, one is allowed to have two small meals of 250-300 calories. According to Michael Mosely, after going through this diet plan for three consecutive months, he reduced roughly 18 pounds. His BMI improved as well as improvement in insulin sensitivity and reduction of IGF13 levels. Research indicates reduced IGF13 levels help prevent cancer and diabetes. In this approach, a person doesn’t stay hungry for a prolonged period and is allowed to have limited meals as long as he stays within the calorie limits. The advantage of this approach is that if one keeps enough proteins in the diet, loss of muscle mass due to the prolonged period of staying hungry can be averted. Muscles are metabolically more active; therefore, in the long run, this has a positive impact.
However, one downside of this method is that there is limited research available. Some references are available for a study involving 107 overweight women, which manifested restricting calories twice weekly and continuous calorie restriction, both leading to similar weight loss. A similar study at a smaller scale depicted the effects of this fasting style in 23 overweight women. Women lost both weight and body fat when they underwent the caloric restrictions for two days per week. However, most women regained the lost weight within a week of regular eating after the fasting cycle.
24-hour fasting:
However, one downside of this method is that there is limited research available. Some references are available for a study involving 107 overweight women, which manifested restricting calories twice weekly and continuous calorie restriction, both leading to similar weight loss. A similar study at a smaller scale depicted the effects of this fasting style in 23 overweight women. Women lost both weight and body fat when they underwent the caloric restrictions for two days per week. However, most women regained the lost weight within a week of regular eating after the fasting cycle.
It is one of the more challenging fasting methods where individual fasts for the entire 24 hours at least once or sometimes twice a week. It is also called the Eat-Stop-Eat diet. Fitness expert Brad Pilon has recommended this method. A person can take tea, coffee, or similar drinks with negligible calories. A beginner can experience headaches, fatigue, and severe cravings, especially in the initial phase of the program. A more relaxed approach is to start with 16 hours fasting and then try to stretch it to 20 hours and later 24 hours. The fasting window depends on the choice of a person. One can take a good breakfast and fast till the next breakfast. The same can be done between two dinners also.
ADF (Alternate Day Fasting):
Another aggressive approach where individuals are required to fast every other day. It is also called “every other day diet”. Compared to the 5:2 method, this approach is more aggressive, and the dieters pursue it for faster visible weight loss. There are several variations of IDF. Most common either use liquid food on alternate days or more commonly restrict caloric input to 500-600 calories per day, similar to 5:2 method. Either way, it is tough for beginners, and people suffering from any medical condition should avoid it or consult their physician before undertaking this diet. Studies have shown reasonable weight-loss averaging around 5KG or 11 pounds over three months. It is an average, and results can vary for different individuals. For some, ADF is the most effective weight-loss method among all, but it is usually more challenging to stick to over a prolonged period.
Alternate fasting is about a day of feasting and a day of fasting.
Warrior Diet:
Fitness expert Ori Hofmekler popularized this diet. It is based on the theory that humans are nocturnal animals, and our eating late in the evening is in sync with our circadian rhythm. So practitioners of this diet are supposed to eat during a 4-hour window late in the evening. For the rest of the 20 hours, they can eat raw vegetables or fruits in limited quantities. In the evening, one can enjoy a large meal comprising of proteins, vegetables, and some carbohydrates. The diet encourages a person to eat food unprocessed and in their naturally occurring state. Again due to the strict requirements, this diet is not easy for beginners, and also, if a person doesn’t choose the menu carefully, it can result in malnutrition.
Conclusion:
Due to the availability of various methods, one can choose the plan that best suits one’s schedule, eating habits, and tolerance to sustain diet intervals. Beginners can start with 5:2 or Leangains (16:8) and later can switch to ADF or 24 hours fasting. Some also suggest that many dieting methods are useful in the beginning but start losing their effect over a long period as the human body can harmonize and adjust itself to the new eating patterns. In such cases, one needs to modify the method to keep the internal body mechanism guessing and thus getting better visible results. Knowledge of different fasting approaches is useful in such cases.
