How can you use intermittent fasting to enhance your gut health?

How can you use intermittent fasting to enhance your gut health?

We are lucky to have so many choices to live out the lives we want to live. By now, you’ve probably been inundated with all kinds of diets that can improve your metabolism. Maybe you found a diet that works for you. Maybe you’re still trying to find what works best.

Society has often conditioned us to believe that only the food we eat matters. But did you know that the periods of time you don’t eat are just as important? Known as intermittent fasting, the times of day and week that you choose not to eat are just as important for your health. Intermittent fasting can take many forms, each of which can help your body’s health when executed correctly.


What is intermittent fasting?

Intermittent fasting involves brief periods where one abstains from eating before returning to their normal eating habits. Intermittent fasting can take many different forms, either for health or religious reasons [1].

  • Complete alternate-day fasting has you alternating between a day of fasting and a day of eating whatever you like. During the fasting days, you would be allowed to drink as many calorie-free beverages as you wish.
  • In modified fasting regimens, you restrict the number of calories you eat to a quarter of your energy needs during fasting days. The 5:2 method is the most popular of these regimens. Here, you take in fewer calories in any two fasting days so long as there is a non-fasting day between them [2]. The other 5 days would see you eating anything else you like.
  • You partake in time-restricted feeding when you only eat within certain periods of the day. Fasting periods typically last for 12 and 24 hours each day.
  • People can also participate in religious fasting if they belong to a belief system. For instance, Muslims participate in Ramadan through time-restricted fasting between dawn and sunset. Many religious fasts fall under one of the kinds of intermittent fasting discussed herein.

    Intermittent fasting, regardless of the form, impacts your body’s ability to break down fat and sugars [3]. During fasting periods, your liver breaks down the fats stored in your tissues into smaller molecules called ketone bodies. Ketone bodies provide you with energy as you fast and signal your body’s cells to behave in a way that benefits your health, aging, and microbiome [4].


    How does intermittent fasting benefit your body?

    Fasting increases the rate your body breaks down fats. Improving the breakdown of fat, in turn, helps improve your body’s metabolic health. In line with this, researchers have identified medical benefits for people who begin an intermittent fasting routine:

    • Repair: Intermittent fasting also turns on a process called autophagy [5]. Autophagy occurs when your cells clean themselves by breaking down unnecessary and malfunctioning cell components [6]. When your cells are overwhelmed with malfunctioning and toxic cell components, your body may show signs of aging. Scientists have observed this phenomenon in neuronal diseases [7], non-alcoholic fatty liver disease [8], and cardiovascular disease [9]. Enhancing autophagy can thus help reduce the risk of multiple degenerative diseases that contribute to aging.
    • Restoration: Intermittent fasting can also help maintain your intestines. It reduces cellular turnover in the small intestine, helping maintain its integrity in the process [10]. Intermittent fasting also helps ensure your gut’s structure through diverse mechanisms that reduce inflammation [11].
    • Intermittent fasting helps optimize your circadian rhythm. The circadian rhythm refers to your body’s internal clock that tells you when to stay awake or go to bed. Your internal clock also helps your body repair and rejuvenate itself, reducing the risk of cancer when optimized [12]. Intermittent fasting can also provide similar improvements to your metabolism [13].
    • Improved weight loss: A systematic review of six studies demonstrated that obese and overweight participants who adopted an alternate-day fasting or a modified fasting regimen saw improved weight loss relative to not fasting at all [14]. Alternate-day fasting can also be as effective as caloric restriction for weight loss, according to a 2022 review [15].


      How does intermittent fasting help your gut microbiome?

      As intermittent fasting involves changes to your digestion, it makes sense that the trillions of microbes living in your gut – the gut microbiome – can also benefit from an intermittent fast. As your gut microbiome reacts, your body will also reap its benefits: 

      • Increased abundance of microbes that produce short-chain fatty acids (SCFAs): A 2021 study determined that spending a single week with 2 days of caloric restriction and 5 days of juice fasting, followed by a plant-based diet, increases the abundance of SCFA-producing bacteria [16]. SCFAs are molecules that help reduce body weight and blood pressure by improving your metabolism, reducing gut inflammation, and preventing a leaky gut. Another 2021 study determined that Muslims taking an intermittent fast during Ramadan saw an increased abundance of SCFA-producing bacteria [17].
      • Intermittent fasts balance the gut microbiome: A study published in 2023 showed that rat models treated with an 18-hour intermittent fasting regimen for 5 weeks saw a reshaping of their gut microbiome [18]. This reshaping resulted in the increased abundance of helpful microbes such as Lactobacillus species.


        Things to consider before starting an intermittent fast

        With all the benefits that can come with intermittent fasting, it’s tempting to jump on the bandwagon and fast right away. However, starting a new diet requires you to speak with your doctor to make sure you won’t have any complications. For example, pregnant women and people with type 1 diabetes should not participate in intermittent fasting [19]. A healthy diet must also accompany intermittent fasts. Failing to maintain a healthy diet in between fasts can cancel out the benefits that intermittent fasting affords. If you’re given the green light to start an intermittent fasting regimen, you can adopt one of the many approaches listed in this article.


        Try out the Injoy app during your intermittent fast!

        Pairing your intermittent fast with the Injoy app will also help you maximize your health. For one, the app will give you personalized recommendations on the foods you should eat outside your fast. It will also make tracking your health during your fast easy and provide you with tailored recipes to follow to meet your metabolic and microbiome needs. Both features of the Injoy app will help you feel satisfied knowing that you’re adopting the best routine for your long-term health and well being.


        Download Injoy for free today on iOS or Android!



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        2. Intermittent Fasting: What It Is, Types and How It Works. Cleveland Clinic. Published March 3, 2022. Accessed March 22, 2023.

        3. de Cabo R, Mattson MP. Effects of Intermittent Fasting on Health, Aging, and Disease. New England Journal of Medicine. 2019;381(26):2541-2551. doi:10.1056/NEJMra1905136

        4. Newman JC, Verdin E. β-Hydroxybutyrate: A Signaling Metabolite. Annu Rev Nutr. 2017;37:51-76. doi:10.1146/annurev-nutr-071816-064916

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        11. Mohr AE, Gumpricht E, Sears DD, Sweazea KL. Recent advances and health implications of dietary fasting regimens on the gut microbiome. American Journal of Physiology-Gastrointestinal and Liver Physiology. 2021;320(5):G847-G863. doi:10.1152/ajpgi.00475.2020

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        19. Intermittent Fasting: What is it, and how does it work? Johns Hopkins Medicine. Published March 1, 2023. Accessed March 23, 2023.

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