Both intermittent fasting and calorie restriction may benefit gut health.

Both intermittent fasting and calorie restriction may benefit gut health.

How Intermittent Fasting and Calorie Reduction Improve Gut Microbiome Diversity

Intermittent Fasting and Microbiome

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Intermittent fasting and calorie reduction are both effective methods of supporting all-important microbiome diversity. A new study from the University of Colorado’s medical school highlights how changes in the gut microbiome, brought about through dietary interventions, can influence gene regulation and overall health.

Both intermittent fasting and calorie reduction diets positively affect the microbiome, the community of bacteria living in a person’s digestive system and throughout the body.

Participants in the study, all of whom had either overweight or obesity, were either instructed to fast for 3 non-consecutive days each week for a year or, alternately, to reduce their regular caloric intake by around 34% over the same period.

An earlier analysis found that the diversity of gut bacteria in individuals’ microbiomes was significantly improved, even at only 3 months into the year-long study. Improvements were seen for both groups — those who fasted and those who focused on reducing their daily calorie intake.

The analysis suggested that a person can improve the diversity of their microbiome and potentially their overall health using the weight reduction strategy of their choice.

The new study reinforces the idea that changes in gut bacteria occur during weight loss. The researchers observed several associations between the abundance of microbes associated with metabolism and obesity and DNA methylation, a process by which gene regulation is altered, potentially impacting our health.

According to Dr. Rudolph Bedford, a gastroenterologist not involved in the study, “The gut microbiome mediates so many different things. It mediates any type of inflammatory process going on within your body.” This inflammation has been linked to conditions such as cancer, diabetes, dementia, and heart disease.

A diverse microbiome is essential for regulating various mechanisms within the body. Dr. Bedford explains, “You want a very diverse microbiome because the more diversity you have, the better variety of function in various aspects of your body you will have. You want a very diverse microbiome in order to decrease and regulate all the mechanisms within your body.” Dietitian Kristin Kirkpatrick adds that “microbial diversity has been associated with a better microbiome. Studies have shown that healthy individuals often have a more diverse gut microbiota. We also see in the data that the greater the beneficial microbes, the greater the change of beneficial health outcomes.”

Why do intermittent fasting and calorie reduction improve microbial diversity? One theory proposed by Dr. Bedford is that the microbiome needs a break, just like we need sleep. By fasting or eating less, we allow the microbiome to rest, repopulate, and improve its diversity.

However, it’s important to note that there is no one-size-fits-all approach to diet. Each individual’s diet needs to be assessed with a health practitioner, especially for pregnant women, breastfeeding individuals, or those struggling with chronic conditions. Moreover, fasting diets and extreme calorie reduction should be avoided by those with a history of disordered eating.

Fasting can be performed in various ways. While the study participants fasted for 3 days a week, fasting can also be done for a few hours or multiple consecutive days. However, caution must be exercised for individuals with diabetes, as prolonged lack of food can cause fluctuations in blood sugar and insulin levels.

Extreme calorie reduction, if taken to the extreme, can disrupt the microbiome and contribute to the increase of pathogenic bacteria in the gut. However, according to Dr. Bedford, extreme calorie reduction is an unlikely practice for most individuals.

In today’s industrialized society, the limited diversity of our food supply, coupled with the use of antibiotics and pesticides, can negatively impact the diversity of the microbiome. This limited diversity has been linked to a rise in colon cancer cases in younger individuals. However, in certain regions referred to as blue zones, where people live exceptionally long lives, a plant-based diet with a diverse range of plant-based foods has been associated with positive changes to the microbiome and better overall health.

In conclusion, both intermittent fasting and calorie reduction have been shown to positively influence gut microbiome diversity, gene regulation, and overall health. By improving the diversity of the microbiome, individuals may potentially reduce inflammation, support better metabolism, and decrease the risk of various health issues. However, it is important to consider individual circumstances and consult with healthcare professionals when making dietary changes. By adopting a diverse and nutritious diet, individuals can enhance their microbiome and potentially improve their well-being.