Updated: May 19
Fasting is an ancient practice that has been used for spiritual and health purposes for thousands of years. In recent years, it has gained popularity as a weight loss tool, nevertheless, some people still have some contention with fasting. Fasting involves abstaining from food or restricting food intake for a certain period of time. There are different types of fasting regimens, each with its own benefits and drawbacks. The process of fasting develops physiological changes in our bodies that we may not see advantages of otherwise. In this post, we'll explore the benefits of fasting for weight loss and discuss different types of fasting regimens. Let's see how fasting affects your fitness goals:
1) Increases metabolic rate: Fasting can help increase your metabolic rate, which can help you burn more calories and lose weight. This is due to an increase in Human Growth Hormone (HGH) which can stimulate protein and carbohydrate metabolism, thus overall improving your resting metabolic rate.
2) Reduces insulin resistance: Fasting can improve insulin sensitivity and reduce insulin resistance, which can help your body better regulate blood sugar levels and reduce the risk of developing type 2 diabetes. Insulin is a hormone that is directly linked to how you’re metabolizing fat. It communicates to your body when to store fat and stop breaking down fat cells. As your insulin levels are regulated your resting metabolic rate increases and you are able to more efficiently burn fat.
3) Promotes fat loss: Fasting can help promote fat loss by increasing the release of growth hormone, which can stimulate the breakdown of fat cells. Human growth hormone allows you to maintain and build muscle while promoting fat loss. Some studies have found that a 24-hour fast can increase HGH production by 2,000 percent in men and 1,300 percent in women. There is also an increase in norepinephrine which is a stress hormone that helps release fatty acids for energy expenditure.
4) Reduces inflammation: Fasting can help reduce inflammation in the body, which has been linked to many chronic diseases, including obesity. This is because digestion is a high-energy process, some foods are more taxing on the digestive system than others and many people consume foods they may be intolerant to without having knowledge of their intolerances.
5) Improves mental clarity: Many people report feeling more mentally clear and focused during a fast, which can help with productivity and overall well-being.
Types of Fasting Regimens:
Intermittent Fasting: This involves alternating periods of eating and fasting. There are several variations of intermittent fasting, including the 16/8 method, which involves eating within an 8-hour window and fasting for 16 hours, this is often achieved by planning the fasting period during sleep. The 5:2 method involves eating normally for 5 days and restricting calorie intake to 500-600 calories for 2 days. The 5:2 method may work best for some people’s schedules and can work if someone enjoys going out on weekends, they may find balance in restricting calories during weekdays.
Water Fasting: This involves consuming only water for a certain period of time. Water fasting can be dangerous if not done properly, and it's important to consult with a healthcare professional before attempting water fasting.
Juice Fasting: This involves consuming only fruit and vegetable juices for a certain period of time. Juice fasting can provide essential nutrients and is a safer alternative to water fasting, but it's important to choose juices that are low in sugar and high in fiber. You can often get away with adding smoothies as well, and adding things like Greek yogurt or protein powders which will leave you feeling satiated much longer.
Alternate-Day Fasting: This involves alternating between days of unrestricted eating and days of fasting or restricted calorie intake. The 5:2 method could fall into this category as well, but this is most often practiced with a full 24-hour fast every so often in between eating days.
Fasting can seem intimidating and it is not for everyone, and it does not always work with our busy schedules. However, there are many studies that show the benefits of fasting on metabolism, insulin resistance, and fat loss. You may want to try different kinds of approaches to fasting to see which one makes you feel better. Remember fasting does not always mean not eating, sometimes dropping your calories significantly will have the same effect on your body. During your first attempts at different approaches, you may find it difficult to adapt to schedules and eating habits, but our metabolisms are great at adapting quickly over time.
Before starting any fitness program or making dietary changes, including supplementation, please consult your physician for a thorough examination.
Nowosad K, Sujka M. Effect of Various Types of Intermittent Fasting (IF) on Weight Loss and Improvement of Diabetic Parameters in Human. Curr Nutr Rep. 2021 Jun;10(2):146-154. doi: 10.1007/s13668-021-00353-5. Epub 2021 Apr 7. PMID: 33826120; PMCID: PMC8102292.
Barnosky AR, Hoddy KK, Unterman TG, Varady KA. Intermittent fasting vs daily calorie restriction for type 2 diabetes prevention: a review of human findings. Transl Res. 2014 Oct;164(4):302-11. doi: 10.1016/j.trsl.2014.05.013. Epub 2014 Jun 12. PMID: 24993615.