Have you heard of intermittent fasting? Basically, it's a lifestyle where you eat for a while, then stop eating, and then start eating again. This way of eating has many health benefits, such as helping with weight loss, improving insulin sensitivity and reducing the risk of diseases such as diabetes and heart disease. There are several different approaches to intermittent fasting, each with its own characteristics. To summarize the most commonly used methods, I have provided a graphical representation of fasting patterns for easy visualization.
Time-Restricted Feeding (TRF)
This involves restricting food intake to a certain period of time each day, usually 4 to 10 hours. This method is often called the 16/8 method because it involves fasting for 16 hours and eating for 8 hours. An example of TRF is skipping breakfast and eating only between 12 pm to 8 pm.
Alternate-Day Fasting (ADF)
This includes alternating fasting and non-fasting periods. Food intake was either severely restricted or not consumed on fasting days, while normal or increased food intake was allowed on non-fasting days. An example of ADF is eating normally on Monday, fasting on Tuesday, then eating normally again on Wednesday.
The 5:2 Day Fasting
This involves eating normally 5 days a week and restricting your calorie intake to 500-600 calories the remaining 2 days. An example of 5:2 fasting is eating normally Monday through Friday, then restricting calories to 500-600 on Saturday and Sunday.
As you may know, both TRF and ADF are forms of intermittent fasting. How often you fast makes a big difference between the two. With TRF, you simply eat at a scheduled time after your daily fast. Instead, ADF requires two fasting days per week. How many calories you consume is another difference. Although you don't have to restrict your calorie intake, you can still only eat TRF at certain times. ADF, on the other hand, calls for strict calorie restriction on fasting days.
Both TRF and ADF can help with weight loss, increase insulin sensitivity, and reduce inflammation. Your preferences and goals will determine which one you choose.
What are the most common challenges?
The top selling book on this topic is "The Complete Guide to Intermittent Fasting" by Dr. Jason Fung identifies several common challenges that people may encounter when practicing intermittent fasting.
Hunger and cravings:
Fasting can be difficult for some people, especially if they are used to eating frequently throughout the day. Hunger and cravings may be particularly strong during the initial period of adapting to fasting.
Low energy and mood:
Some people may experience low energy or mood during fasting periods. This may be due to fluctuations in blood sugar levels or changes in hormonal balance.
Intermittent fasting may not be widely understood or accepted by others, which can lead to social pressure or discomfort when trying to stick to a fasting schedule.
Difficulty fitting fasting into a busy schedule:
Finding time to fast may be challenging for individuals with busy or unpredictable schedules, such as those who work irregular hours or have young children.
Overeating during eating windows:
While intermittent fasting does not typically involve calorie counting or strict food restrictions, some people may find it difficult to control their food intake during eating windows, which can undermine the benefits of fasting.
Overall, the book suggests that these challenges can be overcome with time and practice, and that the benefits of intermittent fasting may ultimately outweigh the difficulties for many people.
Patterson, R. E., Sears, D. D., & Kerr, J. (2017). The Effect of Intermittent Fasting on Health and Disease Risk Indicators: A Systematic Review and Meta-analysis. The American journal of clinical nutrition, 106(4), 1071–1081. https://doi.org/10.3945/ajcn.117.160879
Mattson, M. P., Longo, V. D., & Harvie, M. (2017). Impact of intermittent fasting on health and disease processes. Ageing research reviews, 39, 46–58. https://doi.org/10.1016/j.arr.2016.10.005
Tinsley, G. M., & La Bounty, P. M. (2015). Effects of intermittent fasting on body composition and clinical health markers in humans. Nutrition reviews, 73(10), 661–674. https://doi.org/10.1093/nutrit/nuv041
Fung, J. (2016). The Complete Guide to Intermittent Fasting. Victory Belt Publishing.