The Gut–Brain Connection, GLP-1, and 10 Functional Mushrooms That Support Both

The gut and brain are constantly sending messages to each other. Scientists call this the gut–brain axis—a communication network powered by nerves, hormones, immune messengers, and the bacteria living in your gut microbiome.

When this system is supported, many people notice clearer thinking, steadier energy, better digestion, and more balanced appetite cues. One of the key hormones involved in these signals is GLP-1, released from the gut after eating to support satiety and normal insulin responses [2].

Functional mushrooms contain β-glucans, prebiotic fibers, antioxidants, and neuro-supportive compounds that work along these pathways. Below are 10 of the top functional mushrooms—supported by clinical and preclinical research—that influence the microbiome, the gut–brain connection, and healthy GLP-1 signaling.

How Mushrooms Support the Gut–Brain Axis

Picture the gut and brain as two bedrooms connected by a long hallway. Mushrooms help keep that hallway calm and open by:

• Feeding good gut bacteria. Mushroom polysaccharides act as prebiotic fuel. More balanced bacteria = clearer signals sent to the brain [1,5].
• Supporting brain health. Some mushrooms contain compounds studied for cognitive support and nerve protection [6–8,13].
• Influencing GLP-1, the "gut messenger" hormone. GLP-1 is one way the gut talks to the brain. In simple terms, when GLP-1 is released, it helps your body understand:
  • "I'm hungry."
  • "I've eaten enough."
  • "I feel satisfied now."
  A human clinical trial found that oyster mushroom powder helped support healthier post-meal GLP-1 signals [4].

Together, these effects help support digestion, cognitive function, mood balance, and overall gut–brain harmony.*

1. Lion's Mane (Hericium erinaceus)

Lion's Mane contains hericenones and erinacines—compounds shown to stimulate nerve growth factor (NGF) activity in preclinical studies [6]. In human research, adults taking Lion's Mane for 8–16 weeks showed improvements in cognitive function and mood parameters [7].

Lion's Mane polysaccharides also act as prebiotics, supporting beneficial gut bacteria and gut–brain signaling [8].

In simple terms: Lion's Mane helps support brain clarity while feeding the gut microbes that communicate with the brain.*

Supports:
• Cognitive health
• Memory and focus
• Healthy gut microbiome
• Gut–brain communication*

2. Reishi (Ganoderma lucidum)

Reishi's triterpenes and β-glucans help support immune balance and gut microbial diversity. Studies show Reishi polysaccharides help maintain a resilient gut environment and balanced immune activity—key components of gut–brain signaling [9].

In simple terms: Reishi helps the body stay balanced, supporting a calmer immune response and healthier gut community.*

Supports:
• Immune balance
• Gut microbial diversity
• Stress resilience
• Gut–brain harmony*

3. Turkey Tail (Coriolus versicolor)

Turkey Tail contains PSK and PSP—prebiotic and immune-supportive compounds. Research shows these nourish beneficial gut bacteria while supporting healthy immune pathways [10].

In simple terms: Turkey Tail feeds good bacteria and supports gut-driven immune messages.*

Supports:
• Microbiome diversity
• Immune function
• Gut barrier integrity
• Gut–brain signaling*

4. Maitake (Grifola frondosa)

Maitake contains grifolan, a β-glucan studied for gut and immune support. Research suggests it may support gut barrier function and microbial diversity [11].

In simple terms: Maitake helps strengthen the gut lining while supporting beneficial gut bacteria.*

Supports:
• Gut barrier integrity
• Microbial balance
• Immune support
• Digestive comfort*

5. Shiitake (Lentinula edodes)

Shiitake contains lentinan, a β-glucan that supports digestive and immune wellness. Human studies show increased beneficial bacteria and improved immune markers after Shiitake intake [12].

In simple terms: Shiitake supports both the gut and immune system at the same time.*

Supports:
• Microbiome diversity
• Immune health
• Digestive support
• Overall vitality*

6. Oyster Mushroom (Pleurotus ostreatus)

Oyster mushrooms are one of the few mushrooms studied directly for their influence on GLP-1. A double-blind crossover trial found meals fortified with oyster mushroom powder supported higher GLP-1 release, reduced hunger ratings, and supported healthy post-meal responses in adults with impaired glucose tolerance [4].

In simple terms: Oyster mushroom may help support the body's natural fullness signals—helping the gut tell the brain, "I'm satisfied now."*

Supports:
• Healthy GLP-1 signaling
• Satiety and appetite awareness
• Post-meal comfort
• Metabolic support*

7. Cordyceps (Cordyceps militaris)

Cordyceps militaris contains cordycepin, a compound studied for supporting energy metabolism and antioxidant pathways. Research suggests it supports stamina, oxygen use, and steady physical and mental energy [13].

In simple terms: Cordyceps helps support natural energy and mental focus.*

Supports:
• Energy and stamina
• Oxygen utilization
• Cognitive performance
• Antioxidant protection*

8. Chaga (Inonotus obliquus)

Chaga is rich in antioxidants and polysaccharides. Research shows Chaga may help support the microbiome and protect digestive tissues from oxidative stress [14].

In simple terms: Chaga supports digestion and helps protect the gut from everyday stressors.*

Supports:
• Antioxidant defenses
• Gut comfort
• Microbial balance
• Overall resilience*

9. Mesima (Phellinus linteus)

Mesima contains immune-supportive polysaccharides and has been studied for balanced immune activity and prebiotic effects [15].

In simple terms: Mesima supports both immune balance and a healthier gut environment.*

Supports:
• Immune modulation
• Gut ecology
• Digestive harmony
• Gut–immune communication*

10. Wood Ear (Auricularia auricula-judae)

Wood Ear provides soluble fibers and polysaccharides that support digestion and metabolic wellness. Research shows it supports gut ecology and healthy cholesterol metabolism within normal ranges [16].

In simple terms: Wood Ear supports smooth digestion and healthy metabolic balance.*

Supports:
• Digestive comfort
• Microbial diversity
• Metabolic well-being
• Gut–brain balance*

The Bottom Line

Functional mushrooms influence the gut–brain axis by:

• Feeding beneficial gut bacteria
• Supporting gut barrier integrity
• Providing neuro-supportive compounds
• Supporting healthy GLP-1 signaling
• Modulating immune pathways that affect brain function

By supporting the gut, the brain benefits too—creating a ripple effect of wellness throughout the body.*

FAQ: Functional Mushrooms, the Gut–Brain Axis & GLP-1

1. What is the gut–brain axis, and why does it matter?

The gut–brain axis is the communication pathway between the gut and the brain. It uses nerves, hormones, and gut microbes to send messages in both directions. When the gut is supported with prebiotic fibers, a balanced microbiome, and healthy digestive function, the brain benefits through clearer signaling, improved mood balance, and steadier energy.*

2. How do mushrooms support the gut–brain connection?

Functional mushrooms contain β-glucans, antioxidants, and other compounds that help:

• Feed beneficial gut bacteria

• Support the gut barrier

• Provide neuro-supportive compounds

• Support balanced immune signaling

These combined effects help maintain a calm, steady communication pathway between the gut and brain.*

3. What is GLP-1, and why is it important?

GLP-1 (glucagon-like peptide-1) is a hormone released from the gut after eating. It plays key roles in satiety, appetite control, and post-meal comfort. GLP-1 also communicates directly with the brain. Healthy GLP-1 signaling helps your body recognize:

• “I’m hungry.”

• “I’ve eaten enough.”

• “I feel satisfied now.”

Research shows that dietary fibers, including those from mushrooms, can influence GLP-1 responses [3–4].*

4. Which mushrooms are best for supporting cognitive function?

Lion’s Mane is the most researched for brain support due to compounds that stimulate nerve growth factor (NGF) in preclinical studies [6] and improve cognitive markers in humans [7].
Cordyceps, Reishi, and Chaga also offer antioxidant and wellness-supporting benefits that may indirectly support cognitive health.*

5. Which mushrooms support gut health the most?

Turkey Tail, Shiitake, Maitake, Reishi, and Wood Ear are particularly rich in prebiotic β-glucans that help support:

• Microbial diversity

• SCFA production

• Gut barrier integrity

• Immune balance

These factors are essential for gut comfort and healthy gut-brain communication.*

6. Can mushrooms naturally support GLP-1 signaling?

Human clinical research shows oyster mushroom powder can support healthier GLP-1 release and satiety after meals [4]. While this does not make mushrooms a GLP-1 drug, it demonstrates how mushroom fibers may influence hormone-related gut–brain signaling.*

7. How long does it take to notice benefits from functional mushrooms?

Most studies show gradual benefits when mushrooms are used consistently.

• Gut-related changes (microbiome, digestion): often within 2–4 weeks

• Cognitive support (Lion’s Mane): typically 6–16 weeks

• Energy and stamina (Cordyceps): often within a few weeks

Everyone is different, but consistency is key.*

8. Can multiple functional mushrooms be used together?

Yes. Research suggests combining species that provide different β-glucans, antioxidants, and bioactive compounds may create broader support for the gut, immune system, and cognitive function. This is why multi-mushroom approaches are widely used in traditional wellness systems.*

9. Are functional mushrooms safe for everyday use?

Most functional mushrooms have long histories of traditional use and are generally well tolerated. However, people who are pregnant, nursing, taking medications, or managing health conditions should consult a healthcare provider before adding mushroom supplements to their routine.*

10. Do functional mushrooms contain caffeine or stimulants?

No. Functional mushrooms do not contain caffeine. Mushrooms like Cordyceps may support energy and stamina by influencing oxygen use and cellular metabolism—not by stimulating the nervous system.*

FDA Disclaimer

This content is for educational purposes only. These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

References (All PubMed-Indexed)

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