Can Intermittent Fasting Boost Gut Health?

Intermittent fasting has gained recent hype in the health and wellness industry. In fact, in 2019, intermittent fasting was one of the most searched diets according to Google Trends 1


While intermittent fasting may not be for everyone, research suggests that intermittent fasting may provide significant health benefits, especially for improved gut health.


This article will explore what intermittent fasting is as well as the benefits of intermittent fasting with a particular emphasis on how this pattern of eating can boost gut health.  


Knife and fork next to a white plate against a blue background


What is intermittent fasting?


Before delving into the details of how exactly intermittent fasting may improve gut health, it’s important to understand what intermittent fasting is. 


Unlike many fad diets, intermittent fasting doesn’t dictate what you can and cannot eat, but rather, places emphasis on the timing of eating.


How to do intermittent fasting?


There are many ways in which someone could choose to integrate intermittent fasting into his or her lifestyle. 


One of the most common methods is called the 16/8 method in which fasting occurs for 16 hours daily, while eating occurs for 8 hours. For example, eating may occur between the hours of 12-8pm.


Other versions of intermittent fasting may include fasting for 24-hours once per week, or restricting calories to 500-600 calories daily a couple times per week. 
Research suggests that intermittent fasting creates physiological changes within the body that may provide health benefits, which will be discussed in the next section. 


Wooden plate with a knife and fork displayed as clock hands


What are the benefits of intermittent fasting?

Studies suggest that intermittent fasting may in fact have many health benefits. 


Some of the most significant benefits include improvements to the immune system, as intermittent fasting can reduce inflammation and insulin resistance which in turn helps to strengthen the immune system 2.


Other benefits include enhanced mental clarity, heart health benefits, blood sugar regulation, and improving the health of the gut.


In fact, the research surrounding intermittent fasting and how it relates to gut health is on the rise. This article will focus primarily on intermittent fasting and gut health. 

How does fasting help gut health?


May Strengthen The Gut Barrier 


The gut is hard at work digesting the many foods we feed it on a daily basis. Fasting enables the gut to rest and restore so it can function optimally. 


This may be especially pertinent to those with increased gut permeability, otherwise known as “leaky gut”, a situation in which the gut lining is weakened, allowing toxins and food particles to easily enter the bloodstream. This can trigger an inflammatory process and symptoms such as headaches, fatigue, and bloat.


Research suggests that intermittent fasting may improve our gut-barrier function.


One way it does this is by enhancing antioxidative pathways and even reversing inflammation in the intestines, as seen in clinical studies on Inflammatory Bowel Disease 34


What’s more, when the gut barrier is strong and healthy, it enables a more optimal environment for healthy bacteria to live and flourish. 


Chalkboard drawing graphic showing bacteria moving through the gut


May Boost Microbiome Diversity


Research also suggests that intermittent fasting increases microbial diversity 5It is widely accepted that a more diverse bacterial environment in our intestines leads to a healthier gut function. The bacteria in our guts play an important role in many aspects of our health. Some bacteria help synthesize certain vitamins, such as vitamin K, vitamin B12, or thiamin.


Other bacteria help ferment fibers from our foods and produce compounds called short-chain fatty acids. Some examples of short-chain fatty acids include acetate, butyrate, and propionate. These short-chain fatty acids are vital to maintaining a healthy environment in the gut, and in turn our immune system and metabolic function 6


Because different gut bacteria are responsible for different functions, it is important to have a healthy and diverse environment of intestinal bacteria for optimal health and gut function.


In order to optimize the diversity of our gut bacteria, intermittent fasting is a great dietary practice to encourage gut microbiome diversity. 


May Improve Gut Motility 


Gut motility is the coordinated movement of the gut muscles to keep our food moving through our digestive systems from start to finish. Normal gut motility is vital for the movement of food, bacteria, and waste through our digestive tract.


Research suggests that intermittent fasting may play a role in regulating an important feature of gut motility: the migrating motor complex (or MMC). 
The migrating motor complex is the system of nerves in the intestines that causes cyclic wave-like patterns throughout the gut. These cyclic patterns act as “cleansing waves” in the gut, helping to move out bacteria from the small intestine to the large intestine where most of it belongs. 


The MMC can be thought of as a necessary housekeeping process necessary to maintain optimal gut health. Without it functioning properly, studies show that bacterial overgrowth in the small intestine can be more prevalent. Bacteria overgrowth in the small intestine is a common cause of uncomfortable bloating and gas. 


Interestingly, the MMC occurs only during a fasted state either between meals or overnight during our sleep 7.  For those with Irritable Bowel Syndrome (IBS), there is a dysfunction in their migrating motor complex.


However, there is some speculative research to suggest that intermittent fasting improves the function of and helps to regulate the MMC to improve symptoms of IBS such as irregular bowel movements and bloating. 


Other tips to optimize gut health


Besides intermittent fasting, there are many things we can do to optimize gut health. However, it is important to keep in mind that the gut is quite complex and there is definitely no one-size-fits-all approach. 


Depending on individualized bacterial make-up, pre-existing conditions,  as well as dietary and lifestyle habits, the best interventions will very likely vary for different people. However, there are some simple steps that we all can take to boost the overall health of our digestive systems.


Aerial view of a spread of vegetables and fruits


Here are a few tips:
  • Hydrate –  Adequate hydration is a key component of having a healthy gut. It is recommended to drink about half of your body weight in ounces each day.  
  • Exercise Regularly – Regular exercise helps encourage healthy gut bacteria and also helps maintain normal motility 8.
  • Eat a fiber-rich diet – Fiber helps provide bulk in the intestines, which keeps regular motility and encourages normal bowel movements. Plus, some fibers known as non-fermentable fibers act as “fuel” for the healthy bacteria in our guts to feed off of. The average adult male needs about 38g of fiber daily, and females need about 25g of fiber daily. 
  • Consume probiotic-rich foods – Probiotics are healthy, live bacteria that promote a healthy gut. It is a good idea to consume probiotic-rich foods on a regular basis. Some foods high in probiotics include yogurt, kefir, kombucha, sauerkraut, kimchi, and miso. 
  • Practice mindfulness and/or meditation – Integrating meditative practices into your daily routine are great ways to help reduce stress and in turn, improve gut health. There are links between the disturbed gut microbiome and stress and anxiety. Therefore, finding ways to reduce stress such as meditation may have positive effects on the health of the gut 9

The best way to break a fast

When breaking a fast, it is important to consume nutrient-dense, nourishing foods that are rich in vitamins, minerals, protein, and healthy fats.  Consuming collagen protein is a great source of protein to break a fast while intermittent fasting.


Plus, there may be added benefits of consuming collagen for gut health, too. In fact, studies show that collagen peptides supplementation may improve the integrity of the gut lining 10


Naked Collagen product image with a tub of Naked Collagen next to a pineapple


Here is a fantastic gut-boosting smoothie recipe that is perfect to consume to break a fast:


Gut-Boosting Collagen Smoothie


  • 2 scoops collagen protein powder
  • ½ cup frozen pineapple 
  • 1 banana 
  • 1 handful of kale 
  • 1 tsp packed grated ginger 
  • 1 tablespoon chia seeds
  • 1 cup of milk or kefir (cow’s milk or your favorite non-dairy alternative)


    Blend all ingredients together and enjoy!