There are many reasons to try fasting. After all, our ancestors have been doing it for centuries. However, science is just starting to catch onto all the benefits of intermittent fasting for gut health. It’s been linked to improving insulin sensitivity, normalizing your circadian rhythm, and improving your overall health. Much of these reasons are due to the fact that our gut bacteria play a large role in our metabolism and intermittent fasting gives our metabolic processes a bit of a break.
Unfortunately, many people do not realize how their own gut even functions. They are unaware that inside our gut lives millions of microorganisms. These microbes are in charge of a lot of things, including the digestion of food that we consume. Due to this negligence, many people do not take proper care of their gut. Poor gut health is why so many suffer from gastrointestinal issues.
With so many different treatments out there, you might want to know what you can do to naturally bring your body back into balance. Try doing as our ancestors did. Withhold food from your system for a specific amount of time. Intermittent Fasting for gut health might be what you needed to rebuild gut flora and replenish beneficial bacteria in your gut biome.
What is Intermittent Fasting?
Intermittent fasting, or IF for short, is considered a diet by some but in reality, it’s not. There is no scientific formula to follow intermittent fasting. It’s just fasting in between spurts of time.
While that may sound too simple to be true, IF isn’t very complicated. There are no dietary restrictions. The only restriction is when you eat. During the fasting periods, you can only drink water, coffee, or tea with little to no sweetener. During your feeding time, it’s fair game for food.
This may seem too good to be true, yet there are many benefits of Intermittent Fasting. Essentially, you normally eat for a particular amount of time and then fast for the rest. There are many ways in which people go about with this pattern. These are called protocols.
Types of Intermittent Fasting for Gut Health Protocols
What makes intermittent fasting for gut health such a viable lifestyle choice for many is that you can pick and choose from different protocols. From there, you can make these protocols work with your schedule.
The many ways to do I.F.
No matter the time window you decide for your intermittent fasting protocol, you can make it fit within your daily schedule. Figure out the times that you need the most energy, when you normally eat, and when you can go the longest without eating.
From there, you can try out these three popular intermittent fasting for gut health protocols:
• 16:8 or 18:6 method (can even be 20:4, etc): This is where you fast for 16 to 20+ hours, and eat for the remaining hours in the day. This is the most common method.
• The 5:2 method: In this method, you eat for 5 days, but for two days, you fast. This fasting can include not consuming any calories at all for these days, or have a very low-calorie limit. This limit is usually around 500 calories max.
• One Meal A Day (OMAD) method: Probably the least common of the bunch, but gaining popularity. This is where you eat one large meal a day, and then fast for the rest of the time.
These are just a few of the many different ways that people do IF. There are more intense protocols that include 24-hour fasts, Eat Stop Eat, and Alternate-Day Fasting.
However, these three are the most common intermittent fasting protocols. They are a lot less extreme and easier for you to ease into.
How Intermittent Fasting Improves Gut Health
Now, why should you do intermittent fasting for gut health? Here are some reasons why your gut biome needs a timeout from the digestion of food.
Intermittent fasting gives your body the break it needs to repair itself!
Gives Digestive System a Break
When it comes to our gut health, what we put into our body affects which microorganisms grow and flourish within your gut. What we eat draws a fine line in the sand between probiotic bacteria and harmful bacteria.
Unhealthy diets laden in saturated fatty acids, refined sugars, and artificial sweeteners can cause an inflammatory response from the immune system. Over time, this response only worsens and can contribute to development of disease states such as autoimmune diseases.
Healthy gut microbe communities don’t know how to handle this situation. For one, they don’t like the sweets and junk food. So, they don’t help you digest these foods. That causes weight gain and more inflammatory responses.
Eventually, the chronic inflammation will start to destroy beneficial gut flora. In turn, nutrient availability, immune system support, and metabolic states all suffer.
A long-term diet of consuming junk foods causes helpful microorganisms throughout the digestive tract to die off. Beneficial bacteria relies on the nutrition of whole foods, lean proteins, and complex carbohydrates to prosper. As a result, opportunistic microbes will take their place, ultimately throwing your body into disarray .
This is why consuming more fermented foods, such as yogurts and Kombucha teas are beneficial to the gut. Without these vital microorganisms, our bodies simply would not be able to function.
Or, as Harvard states:
“In a healthy body, pathogenic and symbiotic microbiota coexist without problems. But if there is a disturbance in that balance—brought on by infectious illnesses, certain diets, or the prolonged use of antibiotics or other bacteria-destroying medications—dysbiosis occurs, stopping these normal interactions. As a result, the body may become more susceptible to disease .”– Harvard
Focusing on what we eat and put into our bodies can help us in the long-term to be healthy. In the case of “You can’t say anything nice, don’t say anything at all,” if you can’t find anything healthy to eat, maybe you shouldn’t eat anything at all. That’s what is so beneficial about intermittent fasting for gut health.
Stops Bored Eating and Weight Gain
The thing we have to understand is that we as humans never had 24-hour access to food until very recently. Before this, we ate what was available, and often went long stretches of time without ever eating at all. Not to mention, what they ate was in whole food form and didn’t cause the gastrointestinal distress we all feel today. This is due to the fact that food was not as abundant nor stuffed with additives as it is today.
While food being readily available is convenient for our fast-paced lives, this abundance is a breeding ground for over-consumption.
Present day humans are now eating every couple of hours, if not sooner. This means that our body is in a constant state of digestion, with little rest in-between. It’s like working an 18-hour shift and only getting a five-minute break.
Recent Studies on Intermittent Fasting for Gut Health in Animal Models
Always stuffing our face can overwork our microbiome. Overeating may cause many of the organisms that we take for granted to die off or exponentially grow. Either way, it disrupts the dynamic of our intestinal flora which results in many gastrointestinal symptoms.
There are actually a fair amount of studies that prove this as well. One study on rats found that intermittent fasting was able to restore the microbiome of the rat after just 18 weeks .
A study that was done on fruit flies in 2015 even stated that IF can help to make you live longer . It is important to know that these are animal studies. More research needs to be done before a final conclusion is made.
Recent Studies on Intermittent Fasting for Gut Health in the Human Body
While the studies on intermittent fasting for gut health are predominantly conducted on animals, there has been some human studies done, as well.
There was a 2014 review about if intermittent fasting can help those who suffer from Metabolic Syndrome . The Abstract in this study noted the many benefits of intermittent fasting for gut health, mental wellness, and cellular function.
The meta-analysis noted,
“Chronic fasting extends longevity in part by reprogramming metabolic and stress resistance pathways. In rodents intermittent or periodic fasting protects against diabetes, cancers, heart disease and neurodegeneration, while in humans it helps reduce obesity, hypertension, asthma and rheumatoid arthritis. Thus, fasting has the potential to delay aging and help prevent and treat diseases while minimizing the side effects caused by chronic dietary interventions.– Cell Metab.
Doctors are now becoming more privy to the potential of intermittent fasting for gut health, which can benefit millions of people worldwide.
Prevents Insulin Resistance And Boosts Immune System
A study involving diabetic mice found that type 1 db mice secrete insulin after intermittent fasting. Prior to the study, experts destroyed the β-cells of these animal models.
β-cells are an integral part of the immune system, as they are responsible for secreting insulin. These immune system cells regulate blood glucose levels.
Over eight weeks, the scientists would alternate these mice between a normal diet of free feeding for a week and a week of calorie restriction. In the end, the mice saw a significant increase in β-cells.
Type 2 db mice were also given the same experiment.
• Reduced Level of Fasting Glucose
• Improved Glucose Tolerance
• Better Insulin Sensitivity
These health benefits are not only promising for maintaining the blood sugar levels of diabetics, they can be a game-changer in repairing metabolic health.
Improves Gut Bacteria and Weight Loss
Evidence has come to light in recent years which suggests that gut bacteria may play a crucial role in body weight. Studies have shown that people who are overweight and obese often have a smaller amount of a specific type of bacteria in the gut called Bacteroidetes .
Also, harmful bacteria can cause you to crave refined sugars and processed foods. Therefore, when you have a microbial imbalance in your gut, you will naturally increase food intake.
Lastly, gut bacteria play an integral role in our carbohydrate energy metabolism. They feast on the fibers in carbohydrates, and produce microbial metabolites that help give us an extra boost of energy. With elevated energy levels, you are more likely to exercise and burn off more calories.
A more efficient energy metabolism will keep your circadian clock running smoothly. In time, your sleep levels and body weight should even out. You will notice better cognitive function, improved moods, and regulated metabolic health.
That is why improving gut bacteria and lower body weight go hand-in-hand. To rebuild gut flora that is beneficial to your overall wellness, you should take personalized probiotics supplements.
Combining Intermittent Fasting with Microbiome Testing
At Thryve, we use microbiome testing to determine which intestinal flora is lacking in your gut biome. We then recommend probiotic supplements to rebuild gut flora and eliminate different types of bacteria that might be harmful to your particular system. With our program, we can help retain the balance of beneficial gut flora in your body.
While your probiotics are still growing in your gut biome, you need to give them a better chance of survival. This is where calorie restriction may be beneficial.
Intermittent fasting has shown to be just as effective as any other form of diet when it comes to weight loss. Not to mention, the analysis Bacteroidetes showed that losing weight naturally increases the presence of this gut bacteria. Therefore, when you lose weight with IF, you are potentially increasing beneficial bacteria that live in your body. Over time, this may help keep the weight off.
IF and Reduction of Foodborne Illness
Caloric restriction gives the digestive system a break. Instead of your probiotic bacteria breaking down food particles, they can fight off pathogens. Forgoing meals can have a positive effect on the gut microbiome within three days.
A small study following Salmonella-infected mice, found that IF was able to help them “reset” their gut microbiome .
According to the study:
“…the changes following metabolic stress induced by intermittent fasting during food deprivation days increased the resistance to S. Typhimurium infection by triggering intestinal IgA production and presumably, pathogen elimination by phagocytic inflammatory cells.”– Wiley Online Library
By not eating for periods of time, it gives your body a chance to go back to a state of balance. With gut biome balance, your intestinal flora can diversify, and multiply alongside other beneficial bacteria.
Intermittent Fasting Regulates Circadian Rhythm Metabolism
All cells follow a 24-hour cycle for optimal replication. This physiological process is known as our metabolism. That time period is known as our circadian rhythm
When you are trying to repair your gut lining from chronic inflammation, it is essential for our epithelial tissue, immune system, and blood cells all follow our circadian clock.
Unfortunately, our body works overtime, throwing off our circadian rhythm. For one, our circadian clock is light-dependent. It relies on our pineal gland, taking in light from the sun to know when it’s daytime and nighttime.
During the day, the body is all-hands-on deck. It’s working on glucose metabolism for energy, keeping your skin looking vibrant, and helping you lose weight. However, electronics are throwing off our pineal gland.
Blue light emitted from devices is throwing off our brain function, telling our pineal gland that the sun is rising at all hours. Too much screen time messes up your cells’ physiological processes.
Your body also relies on these light cues to get sleep. That way, your immune system can take a break. Then, your body can produce the hormones it needs for tomorrow and begin repairs on the wear-and-tear of adulting.
Unfortunately, eating all the time throws even more wrenches into our circadian rhythm. When you eat close to bedtime, your body never stops working.
So, your cells don’t go through their regular processes. Instead, they’re busy digesting your food. Then, you’re going to feel bloated and tired the next day!
Most people follow a fast diet during their sleeping hours. Being unconscious when you’re hungry means you won’t think about the fact you want food! Plus, your body is free to work on fixing your metabolic health, rather than breaking down your food.
Also, try to plan your meals at the same time. Your body should anticipate when to have the healthy gut microbial communities ready to get to work. Likewise, stay regular with your bedtime. The more of a routine you follow, the better gut health you will experience.
Trying Out Intermittent Fasting for Gut Health
I.F. can be beneficial to our health in a variety of ways. It can help with replenishing gut bacteria and weight loss. Intermittent fasting may also reduce inflammation and curb overeating.
While previous research on adults for intermittent fasting has been promising, there hasn’t been any science done for the elderly or for children. You should always consult a physician anytime you make dietary changes. However, it’s extremely important when dealing with the elderly and the young.
Also, if you have a history with eating disorders, chronic calorie restriction isn’t considered a healthy eating pattern. While intermittent fasting is a useful tool for improving bacterial diversity, you don’t want to jeopardize your mental or overall health.
If you are having gastrointestinal issues or you feel as if your gut health is not in balance, try IF. The benefits of fasting might be able to help get your gut balance back on track.
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