In the internet world, Intermittent fasting (IF) is seldomly heard and is discussed. This is another popular strategy that is used in weight management. IF is all about when you eat and focuses on fasting and feeding windows.
In prehistoric times our ancestors collected food by hunting and gathering. These tasks took lots of energy and time, our bodies were adapted to go without food for long hours. Today also our bodies can function for quite a while without food.
Earlier, weight management was easier as portions were smaller and activities were greater. Now with emerging technology lifestyle disorders like type 2 diabetes, heart diseases, and others have become very common. IF is considered one of the ways to manage these lifestyle disorders too.
What is Intermittent fasting?
It's a diet approach that divides the total daily food consumption into a set number of concurrent hours, resulting in a fasting period that can last up to 24 hours. One might, for example, choose to eat all of their meals inside an 8-hour window each day. They'd have nothing but water, black coffee, or tea for the next 16 hours (items with no calorific value).
As a result, an intermittent fast of 16 hours per day would be required. IF makes no mention of calorie intake or macronutrient distribution. As a result, this cannot be called a diet, but rather a time-limited technique that people employ for a variety of health and convenience reasons.
Because of our 7–8-hour sleep, we all unconsciously undertake intermittent fasting to some extent.
Popular types of Intermittent fasting
| 16:8 type fasting | In this type of intermittent fasting a person eats within 8 hours and fasts for 16 hours, this fasting can be paired with 7-8 hours of sleep. In the fasting window, one can have calorie-free things like water or even a diet soda would be ok. |
|---|---|
| Alternate day fasting | Fasting on alternate days and not eating at all and alternated days feasting on food without caloric restrictions |
| Modified Alternated day fasting | Consuming less than 25% of your BMR calories on fasting days and feasting on alternated days. For example, if a person's BMR is 1400 kcals they should consume 350 kcals on fasting days |
| 5:2 Fasting | Fasting for 2 days eating absolutely nothing and rest 5 days eating normally timed meals. The two days can be adjusted in between 5 days so as to avoid extreme low energy feeling. |
How does Intermittent fasting work:
The body must maintain the needed blood glucose levels in order to perform its normal operations, whether fasting or fed. The body, on the other hand, leaves the fed state and enters a fasted state after several hours of fasting.
Fasting for 12 to 24 hours lowers serum glucose levels and depletes glycogen in the liver to provide energy if blood glucose drops by 20% or more, depending on an individual's degree of physical activity. The metabolic mode is subsequently switched to other sources ie free fatty acids as energy sources in short it starts burning fat.
As a result, when food intake is stopped and glycogen is depleted, fat stores are used as energy, resulting in fat loss while fasting. During that eating window, however, the body is sophisticated enough to store any surplus energy as fat and rebuild fat stores.
It is clear that regardless of which dieting approach we adopt, energy equations that is calories in vs Calories out are the clear leader.
Conclusion:
If intermittent fasting works well with your lifestyle and helps you manage your calories as per your goals, it is a powerful tool that can be used. However, if it does not suit your lifestyle, there is a chance for it to backfire too. Therefore, one has to choose wisely that can be followed with long-term sustenance.
References:
Antoni, R., T. M. Robertson, M. D. Robertson, and J. D. Johnston. 2018. A pilot feasibility study exploring the effects of a moderate time-restricted feeding intervention on energy intake, adiposity and metabolic physiology in free-living human subjects. Journal of Nutritional
Lewgood, J., Oliveira, B., Korzepa, M., Forbes, S. C., Little, J. P., Breen, L., Bailie, R., & Candow, D. G. (2021). Efficacy of dietary and supplementation interventions for individuals with type 2 diabetes. Nutrients, 13 (7). https://doi.org/10.3390/NU13072378
Wilkinson, M. J., E. N. C. Manoogian, A. Zadourian, H. Lo, S. Fakhouri, A. Shoghi, X. Wang, J. G. Fleischer, S. Navlakha, S. Panda, et al. 2020. Ten-hour time-restricted eating reduces weight, blood pressure, and atherogenic lipids in patients with metabolic syndrome. Cell Metabolism 31 (1):92–13. doi: 10.1016/j.cmet.2019.11.004.
