What are the 4 bacteria for longevity? The Science of a Youthful Gut

January 12, 2026 •

5 min read

Research on supercentenarians—people living past 100—revealed a distinct gut microbiome teeming with beneficial bacteria, suggesting a link between a youthful gut and exceptional longevity. This has led to the question: what are the 4 bacteria for longevity, and how can we cultivate them to support our own healthy aging?

Quick Summary

Examining centenarian microbiomes has highlighted key bacterial groups associated with extreme longevity, including Akkermansia, Christensenella, and Bifidobacterium. These microbes are critical for maintaining gut barrier integrity, producing anti-inflammatory compounds, and supporting overall health as we age.

Key Points

Microbiome Shifts with Age: The gut microbiome's diversity typically declines with age, a process counteracted in exceptionally long-lived individuals.
The 'Superager' Signature: Centenarians often possess a youthful and distinct gut microbiome profile rich in specific bacteria like Akkermansia and Christensenella.
Mucus Layer Fortification: Akkermansia muciniphila helps reinforce the protective mucus lining of the gut, reducing systemic inflammation.
Genetics and Leanness: The abundance of Christensenella minuta is influenced by genetics, is associated with a lean body mass index, and is consistently found in centenarians.
Anti-inflammatory Production: Species like Odoribacter and Bifidobacterium are linked to longevity due to their anti-inflammatory properties and ability to regulate immune function.
Dietary Foundation: A diet rich in fiber (prebiotics) and fermented foods (probiotics) is the most effective strategy for fostering a diverse and beneficial gut microbiome.

The Gut Microbiome's Role in Healthy Aging

The gut microbiome is a complex ecosystem of trillions of microorganisms that profoundly impacts overall health, from digestion to immune function. As we age, this microbial community naturally shifts, often leading to reduced diversity and an increase in inflammation-associated microbes, a phenomenon known as 'inflammaging'. However, studies of individuals with exceptional longevity, particularly centenarians and supercentenarians, show a contrasting and more youthful microbial profile. This unique gut signature often involves a higher abundance of specific beneficial bacteria, highlighting the potential for the microbiome to influence healthspan—the period of life spent in good health. Scientists are now focusing on identifying the key microbial players and understanding their functions to help more people achieve a healthier old age.

What are the 4 bacteria for longevity? The Centenarian Microbiome

While the concept of exactly four bacteria for longevity is a popular simplification, research has pointed to several candidates that appear more frequently or robustly in the guts of long-lived individuals. Based on observations by researchers like Dr. William Li, four prominent candidates often emerge from studies on superagers.

1. Akkermansia muciniphila: The Mucus Layer Guardian

This bacterium is a standout for its unique function: it colonizes and feeds on the intestinal mucus layer. This might sound counterintuitive, but by doing so, it stimulates the gut lining to produce more mucus, thereby reinforcing the intestinal barrier. A stronger gut barrier helps prevent toxins and pathogens from entering the bloodstream, which reduces systemic inflammation—a hallmark of unhealthy aging. High levels of Akkermansia have been observed in centenarians and are linked to better metabolic health and immunity. Mice studies have also shown that supplementing with Akkermansia can extend lifespan and improve age-related health markers.

2. Christensenella minuta: The Inherited Leanness Microbe

The family Christensenellaceae, and specifically the species Christensenella minuta, is one of the most heritable microbes in the gut and is more prevalent in lean individuals with a lower body mass index (BMI). This suggests a strong genetic link to the presence of this bacterium. Like Akkermansia, Christensenella is associated with improved glucose metabolism and is depleted in individuals with metabolic disorders. Its abundance is consistently higher in centenarians compared to younger cohorts across various studies, cementing its reputation as a key microbe for healthy aging.

3. Odoribacter: The Anti-Inflammatory Producer

Odoribacter is another genus found in higher abundance in long-lived families, often associated with a younger-like equilibrium of the gut ecosystem. Studies suggest that Odoribacter splanchnicus plays an important role in mediating immune responses and metabolism, potentially helping to regulate inflammatory processes that accelerate aging. Its presence is associated with a beneficial metabolic profile in centenarians.

4. Oscillibacter: A Potential Youthful Signature

While less is known about Oscillibacter compared to the other three, it has been identified in several studies examining the gut flora of centenarians and is cited by longevity experts as part of the 'superager' microbial signature. Research suggests that, alongside the others, its abundance contributes to a stable and diverse gut environment that resists age-related decay. A high degree of microbial uniqueness and complexity in the gut, which often includes such less common genera, is a strong predictor of healthy aging and extended survival.

Cultivating a Longevity-Supporting Microbiome

Achieving a gut rich in these beneficial microbes is less about taking a specific supplement and more about holistic lifestyle choices. Diet is the primary driver of microbial diversity and function.

Embrace Fiber: Prebiotic fibers are the main food source for many beneficial gut bacteria, including Bifidobacterium and potentially Christensenella. Fill your plate with fruits, vegetables, legumes, and whole grains. Supercentenarian María Branyas Morera, who died at 117, ate a Mediterranean diet rich in these foods.
Prioritize Fermented Foods: Foods containing live cultures, or probiotics, can help introduce beneficial bacteria into your system. Kefir, yogurt (especially with live cultures), kimchi, sauerkraut, and miso are excellent sources. María Branyas Morera reportedly consumed three yogurts daily.
Limit Processed Foods: A diet high in processed foods, sugar, and saturated fats can promote the growth of harmful bacteria and lead to a less diverse microbiome. Reducing these items creates a healthier environment for longevity-associated microbes to thrive.
Exercise Regularly: Physical activity is known to positively influence gut microbiome diversity and reduce inflammation, though the exact mechanisms are still being explored. Consistent exercise is a key component of a healthy lifestyle that benefits the gut.
Manage Stress: The gut-brain axis demonstrates a powerful connection between mental health and the microbiome. Chronic stress can negatively impact gut health, so practicing mindfulness, meditation, and other stress-reduction techniques is beneficial.

Comparison of Longevity-Associated Gut Bacteria


Bacterium	Family/Genus	Primary Function	Centenarian Evidence	How to Foster
Akkermansia	Verrucomicrobiaceae	Reinforces intestinal mucus layer, reduces inflammation.	High abundance found in supercentenarians.	Diet rich in prebiotics, polyphenols.
Christensenella	Christensenellaceae	Associated with lower BMI, healthy metabolism.	High abundance linked to longevity and genetics.	Diet rich in fiber and potentially influenced by genetics.
Odoribacter	Odoribacteraceae	Produces anti-inflammatory compounds, supports healthy metabolism.	Enriched in long-lived families, contributes to younger-like gut equilibrium.	Fiber-rich diet.
Bifidobacterium	Bifidobacteriaceae	Boosts immune function, fights pathogens, produces SCFAs.	High levels in centenarians and supercentenarians worldwide.	Fermented foods (yogurt, kefir), prebiotics.
Bacteroides	Bacteroidetes	Produces anti-inflammatory factors like IL-10.	Higher abundance of beneficial species in centenarians.	Fiber-rich diet.

Conclusion

While focusing on the precise “what are the 4 bacteria for longevity” is a powerful concept for communicating the importance of gut health, the real takeaway is that a rich, diverse, and well-supported gut microbiome is crucial for healthy aging. The specific microbes like Akkermansia, Christensenella, Odoribacter, and Bifidobacterium that have been repeatedly observed in long-lived individuals each play a distinct and complementary role in maintaining a healthy gut ecosystem, from reinforcing the protective mucus layer to modulating inflammation. The good news is that we have considerable control over our gut environment through our lifestyle choices. By prioritizing a diet high in fiber and fermented foods, limiting processed items, and engaging in regular physical activity, we can cultivate a robust and resilient microbiome. This proactive approach may not only extend lifespan but, more importantly, increase the number of years we live in good health.

For more in-depth scientific literature on the topic, a comprehensive review exploring the role of Bifidobacterium in longevity is available through the National Institutes of Health.

Frequently Asked Questions

To foster these beneficial bacteria, focus on a diet rich in prebiotics, which feed the microbes (e.g., fruits, vegetables, legumes, whole grains), and fermented foods (probiotics) like yogurt, kefir, kimchi, and miso, which introduce live, beneficial cultures.

While supplements exist, the most effective way to support your microbiome is through diet. Targeted probiotic supplements containing species like Bifidobacterium longum and B. breve are available, but their effectiveness depends on many factors, and a food-first approach is often recommended.

The gut microbiome influences aging by affecting metabolic processes, immune function, and systemic inflammation. A healthy gut can help reduce chronic inflammation (inflammaging) and improve nutrient absorption, all of which contribute to a longer healthspan.

No, these are not the only important bacteria. Research has highlighted these species for their prominent roles in centenarian microbiomes, but overall microbial diversity and a balanced gut ecosystem are the most critical factors for long-term health.

A diverse gut microbiome means a high number of different microbial species coexisting harmoniously in your gut. This diversity is associated with a healthy, resilient gut ecosystem that can better resist environmental disturbances and inflammation.

Many beneficial bacteria, including Akkermansia and Bacteroides fragilis, help reduce inflammation. Akkermansia fortifies the gut barrier to prevent inflammatory triggers from entering the body. Other species produce anti-inflammatory compounds like short-chain fatty acids (SCFAs) and regulate immune cells.

Yes, antibiotics can significantly disrupt the balance and diversity of your gut microbiome by killing both harmful and beneficial bacteria. While sometimes necessary, overuse can damage the gut ecosystem and potentially impact long-term health.