Does prolonged fasting really reduce inflammation?

Fasting has become more than just a trend; it’s a lifestyle choice for many seeking diverse health benefits. One such benefit often cited is reducing inflammation, a major contributor to chronic diseases. 

But how accurate are these claims? By examining the relationship between nutrition, fasting, and inflammation, this article aims to shed light on the science and research surrounding these assertions. 

Through a careful review of recent studies, we’ll offer a clear perspective on whether prolonged fasting helps mitigate inflammation.

What is inflammation?

Inflammation is the body’s natural response to injury or infection. It can be categorized as either acute or chronic. Acute inflammation is a short-term reaction, often identified by redness, heat, swelling, and pain. 

It’s the body’s immediate way of defending itself when harmed. For instance, think about a cut’s red and swollen appearance a few hours after an injury.

On the other hand, chronic inflammation is a long-term response and can persist for months or even years. Instead of helping the body, this prolonged inflammation can harm it. 

Does prolonged fasting really reduce inflammation?

Diseases like arthritis, diabetes, and even heart disease can be linked to chronic inflammation [1]. The problem begins when the inflammatory response doesn’t turn off and becomes continuous, often due to lifestyle factors like poor diet, stress, or exposure to toxins.

Thus, understanding the distinction between these two types of inflammation is crucial. While acute inflammation is a sign of healing, chronic inflammation might indicate an underlying health issue. Recognizing and addressing the causes can be vital in managing and improving overall health.

How does fasting work?

Fasting, simply put, is the voluntary abstention from food for a set period. It’s a practice that has historical roots, often associated with religious or spiritual rituals. Today, its health implications are widely researched.

From a biological standpoint, our bodies undergo several significant changes when we stop eating for an extended period. Initially, to maintain energy, our body breaks down glucose stored in the liver. Once these stores deplete, the focus shifts to fat cells, leading to the production of ketones, which become the primary energy source.

This metabolic switch, often termed “ketosis”, offers various potential health benefits. One is enhanced brain function due to the brain’s preference for ketones over glucose.

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Moreover, fasting prompts cellular processes like autophagy, where cells remove damaged components [2]. This can be considered a cellular “clean-up”, eliminating faulty parts that might otherwise lead to inflammation or disease.

Additionally, fasting affects hormone levels. Insulin sensitivity can improve, stabilizing blood sugar levels. Growth hormone production can spike, promoting cellular repair.

Understanding these processes helps us appreciate why fasting has gained attention in the health community. Beyond mere weight loss, its potential to optimize bodily functions is a growing area of interest.

Prolonged fasting and inflammation

Overview of scientific studies and their findings

Prolonged fasting, typically extending beyond 48 hours, has been the subject of numerous studies exploring its impact on inflammation.

Animal studies and their relevance

In animal models, notably mice, prolonged fasting has demonstrated a reduction in pro-inflammatory markers [3].

The reduced inflammation was often associated with improved cellular health, suggesting a protective mechanism induced by fasting. These studies provide foundational knowledge, but the direct translation to human physiology requires careful consideration.

Human studies and their outcomes

In humans, the evidence is intriguing and promising. Research indicates that fasting for extended periods can lead to a decrease in several inflammatory markers [4].

Some study participants reported reduced inflammation and other benefits like improved cognitive function and metabolic health. However, individual responses varied, hinting at the complex interplay of genetics, environment, and fasting duration.

Mechanisms: How does prolonged fasting affect inflammation?

The anti-inflammatory effects of prolonged fasting can be attributed to multiple mechanisms working in tandem.

Autophagy and its role in reducing inflammation

Autophagy, the cellular “clean-up” process, is heightened during prolonged fasting. By removing damaged cellular components, autophagy prevents potential malfunctions that might stimulate inflammatory pathways.

The impact on immune cells and cytokine production

Prolonged fasting can influence immune system dynamics. There’s a noted reduction in white blood cells, which, upon refeeding, stimulates the generation of new immune cells.

This “reset” can potentially reduce chronic inflammatory responses. Moreover, a decline in the production of certain pro-inflammatory cytokines during fasting further supports the anti-inflammatory benefits.

Hormonal changes and their influence on inflammatory processes

Fasting triggers various hormonal shifts. Improved insulin sensitivity and reduced insulin levels, for instance, can lead to anti-inflammatory effects. Additionally, changes in other hormones, like growth hormone, can further modulate inflammation.

In essence, prolonged fasting presents a multifaceted approach to reducing inflammation [5]. While promising, it’s essential to consider individual variations and consult with healthcare professionals to ensure the best outcomes.

Benefits of prolonged fasting beyond inflammation

Prolonged fasting, extending beyond simple daily restrictions, holds transformative potential for health. Let’s explore its multi-faceted advantages beyond just curbing inflammation:

1. Renews cells

Extended fasting kickstarts autophagy, a process where cells actively cleanse themselves of damaged parts. This not only ensures optimal cellular function but may also counteract signs of aging.

2. Enhances metabolic health

Fasting sharpens insulin sensitivity, actively guarding against type 2 diabetes. As the body taps into fat reserves for energy, it efficiently burns fats, facilitating weight loss and optimizing lipid levels.

3. Boosts brain health

During fasting, the body produces ketones, powerful fuels for the brain. These compounds not only elevate cognitive performance but also fortify the brain against potential neurodegenerative diseases.

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4. Triggers growth hormones

Fasting triggers a robust release of growth hormones. These hormones drive cellular repair, foster muscle growth, and supercharge metabolism, fast-tracking the body’s recovery from various stresses.

5. Improves cardiovascular health

Prolonged fasting strengthens the heart. The heart benefits from lowered blood pressure, diminished cholesterol levels, and many improved health markers, forging a path to enhanced cardiovascular well-being.

6. Promotes longevity

Some research suggests that prolonged fasting might extend life. Through a combination of cellular rejuvenation, metabolic enhancements, and reduced oxidative stresses, fasting potentially paves the way for a longer, healthier life.

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Potential risks and drawbacks of prolonged fasting

While fasting, especially prolonged variants, is touted for its myriad health benefits, it’s essential to approach it with an understanding of potential risks and drawbacks.

1. Nutrient deficiency: Extended fasting can lead to deficiencies in essential vitamins and minerals. The absence of consistent nutrient intake might compromise overall health if fasting is frequent or extended without proper planning.

2. Muscle loss: While the body primarily targets fat reserves for energy during fasting, there’s still a risk of muscle breakdown, especially if fasting extends for longer periods without adequate protein intake afterward.

3. Dehydration: The body loses a significant amount of water during fasting, and dehydration can quickly set in if one doesn’t compensate with adequate water intake. This can lead to dizziness, headaches, and kidney stress.

4. Hypoglycemia: For individuals, especially diabetics or those with metabolic issues, fasting can cause blood sugar levels to plummet, leading to symptoms like fainting, confusion, or even seizures.

5. Orthostatic hypotension: Fasting might cause a sudden drop in blood pressure upon standing, causing dizziness or fainting.

6. Overeating post-fast: The body’s intense hunger response after a prolonged fast can lead some people to consume excessive calories, negating the benefits of the fast.

7. Emotional and mental stress: Fasting isn’t just a physical challenge. It can strain mental well-being, leading to mood swings, irritability, or feelings of depression.

8. Potential for eating disorders: Individuals predisposed to eating disorders might find that fasting triggers or exacerbates problematic eating behaviors.

9. Medication interaction: Those on medication should consult with healthcare professionals before fasting, as it might affect the medicine’s efficacy or lead to adverse reactions.

10. Underlying health conditions: People with heart conditions, kidney diseases, or other significant health issues should approach fasting with caution, as it can exacerbate existing conditions.

Practical tips if you’re considering prolonged fasting

1. If you’re new to fasting, begin with shorter durations and gradually extend.

2. Drink plenty of water, and consider adding electrolytes if fasting for multiple days.

3. If you feel unusually weak or dizzy, it’s essential to break the fast.

4. Consult a doctor especially if you have pre-existing conditions or take medications.

5. Consume easily digestible foods like broths or fruits initially, avoiding heavy meals to break the fast gently.

6. Educate yourself on the nuances of fasting and its impact on your body.

7. Keep track of your physical and mental changes throughout the fasting period.

Closing thoughts

Fasting, particularly when extended, promises a host of health benefits, from cellular rejuvenation to inflammation reduction. However, its potential also comes with a set of risks, ranging from nutrient deficiencies to heightened emotional stress. 

The body’s response to fasting is complex, nuanced, and varies widely among individuals. As such, it’s crucial to approach fasting with a comprehensive understanding, recognizing both its transformative potential and inherent challenges.

Before embarking on any fasting regimen, it’s imperative to weigh benefits against drawbacks, and for many, consulting with healthcare professionals is paramount. The journey of fasting is as much about knowledge and caution as it is about health transformation.


Does prolonged fasting reduce inflammation?

Yes, research indicates that prolonged fasting can reduce inflammation in the body. This effect is attributed to mechanisms like autophagy, immune system rejuvenation, and hormonal shifts that counteract inflammatory processes.

Does a 48 hour fast reduce inflammation?

Yes, a 48-hour fast has been shown to reduce inflammation in some individuals. The fast can trigger cellular and metabolic responses that contribute to decreased inflammatory markers.

Does autophagy reduce inflammation?

Yes, autophagy plays a role in reducing inflammation by removing damaged cellular components that might trigger inflammatory pathways. This cellular “clean-up” process can help maintain cell health and counteract inflammation.

Does the body heal faster when fasting?

Fasting can stimulate processes like autophagy and the production of growth hormones, which aid in cellular repair and recovery. However, whether the body “heals faster” during fasting depends on the specific context and type of injury or ailment.

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