Can gut problems cause anxiety?

Yes, research strongly suggests a significant link between gut problems and anxiety. An imbalance in gut bacteria (dysbiosis), increased gut permeability (“leaky gut”), and inflammation in the gut can all impact the brain and contribute to anxiety symptoms. The gut-brain axis is a bidirectional communication network, meaning that problems in the gut can send signals to the brain that influence mood, anxiety levels, and even cognitive function. The vagus nerve, the gut microbiome, neurotransmitters, and the immune system all play roles in this complex interaction.

What are the best foods for gut health and mental health?

The best foods for gut health and mental health are those that are rich in fibre, prebiotics, and probiotics, and that support a diverse and balanced gut microbiome. These include a wide variety of fruits (especially berries, apples with skin, and bananas), vegetables (especially leafy greens, broccoli, artichokes, and asparagus), legumes (lentils, chickpeas, beans), whole grains (oats, brown rice, quinoa, whole-wheat bread), nuts and seeds (almonds, chia seeds, flaxseeds), and fermented foods (yogurt with live cultures, kefir, sauerkraut, kimchi, kombucha, tempeh, miso). It’s also important to limit processed foods, added sugar, unhealthy fats, and excessive alcohol consumption, as these can negatively impact gut health.

Should I take probiotics for my mental health?

While some research shows promise for using specific strains of probiotics to improve certain mental health symptoms (particularly anxiety and depression), the research is still evolving, and it’s not a one-size-fits-all solution. It’s essential to talk to your doctor or a registered dietitian/nutritionist before taking probiotic supplements. They can help you determine if probiotics are appropriate for you, considering your individual needs, medical history, and current medications. They can also recommend specific strains and dosages that are supported by scientific evidence for your particular concerns. Probiotics are generally most effective when combined with a healthy, gut-friendly diet and lifestyle.

What is the vagus nerve, and how does it relate to the gut-brain connection?

The vagus nerve is a major cranial nerve (the longest one) that connects your brainstem to many organs in your body, including your gut. It’s a crucial component of the gut-brain axis, acting as a bidirectional communication highway. This means it transmits signals from the gut to the brain, and from the brain to the gut. Information about the state of your gut (e.g., inflammation, nutrient levels, the presence of certain bacteria) is relayed to the brain via the vagus nerve, influencing mood, anxiety, and even cognitive function. Conversely, signals from the brain can influence gut motility, secretion, and the composition of the gut microbiome. Stimulating the vagus nerve (through techniques like deep breathing, meditation, or even cold exposure) can have calming effects and may improve gut health.

What is dysbiosis, and how does it affect mental health?

Dysbiosis refers to an imbalance in the composition and/or function of the gut microbiome. This can involve a decrease in the abundance and diversity of beneficial bacteria, an overgrowth of potentially harmful bacteria, or a loss of overall microbial balance. Gut dysbiosis has been linked to a wide range of health problems, including mental health conditions like anxiety and depression. The mechanisms by which dysbiosis affects mental health are complex and involve the gut-brain axis, including altered neurotransmitter production, increased gut permeability (“leaky gut”), inflammation, and altered immune function.

What is “leaky gut,” and how does it relate to mental health?

“Leaky gut,” also known as increased intestinal permeability, refers to a condition in which the lining of the gut becomes more porous than it should be. This allows undigested food particles, bacteria, and bacterial byproducts (like lipopolysaccharide or LPS) to “leak” from the gut into the bloodstream. This can trigger an immune response and inflammation, which can then affect the brain and contribute to mental health issues like anxiety and depression. Factors that can contribute to leaky gut include gut dysbiosis, chronic stress, a poor diet (high in processed foods, sugar, and unhealthy fats), excessive alcohol consumption, and certain medications (like NSAIDs).

5 Signs It’s Not Just "Stress": The Hidden Symptoms of Adult ADHD

Why your “burnout” might actually be a neurobiological difference related to adult ADHD, not a scheduling failure.

Reading Time: ~5 minutes

Introduction: The “Burnout” Trap

It’s 3:00 PM on a Tuesday. You have three urgent deadlines. You know you should be working. You want to be working. But instead, you are staring at a blank screen, physically unable to type a single word.

You tell yourself, “I’m just stressed. I need a holiday.”

But let’s pause. Stress is a reaction to a trigger. When the trigger goes away (the deadline passes, the holiday starts), stress usually dissolves.

ADHD is different. It is consistent. It follows you on holiday. It is there when you are busy, and it is there when you are bored.

Current data from the Australian ADHD Professionals Association (AADPA) suggests that ADHD affects approximately 6–8% of Australian adults, yet a significant portion remains undiagnosed.^[1] Many high-functioning professionals mask their symptoms for years, relying on anxiety and adrenaline to function, only seeking help when they hit a wall of exhaustion in their 30s or 40s.

If you feel like you are working five times harder than your peers just to achieve the same result, here are 5 research-backed signs that it might be your wiring, not your workload.

1. You Have an “Interest-Based” Nervous System

One of the most critical distinctions between neurotypical burnout and ADHD lies in the neurochemistry of motivation.

If you are burned out, you are generally tired of everything. If you have ADHD, your executive functions are notably inconsistent: you are exhausted by boring tasks but possess infinite energy for novel ones.

Leading clinicians like Dr. William Dodson describe this as an Interest-Based Nervous System (IBNS).^[2]

Neurotypical brains are motivated by: Importance, Secondary Consequences, and Rewards.
ADHD brains are predominantly motivated by: Novelty, Challenge, Urgency, and Interest.

brain motivation styles neurotypical burnout vs adult adhd mind health sydney parramatta — Brain motivation styles

If you cannot summon the executive control to do your taxes (important), but you can hyper-focus for six hours on researching a new niche hobby (novelty), this suggests a deficit in dopamine tonic firing, not a lack of willpower.^[3]

→ Struggling to regulate your focus? Read about our Cognitive Assessments to understand your executive function profile.

2. “Time Blindness” & The Now/Not Now Dichotomy

For the neurotypical brain, time is felt as a continuous linear progression. For the ADHD brain, time is often categorized into two distinct buckets: “Now” and “Not Now.”

Clinical psychologist Dr. Russell Barkley argues that ADHD is fundamentally a disorder of “time blindness”—an inability to bridge the gap between present actions and future consequences.^[4]

The Scenario: A project due in two weeks.
The ADHD Reaction: Because it is in the “Not Now” bucket, it does not emotionally exist. You feel artificially calm.
The Shift: Suddenly, the deadline is tomorrow. It enters the “Now” bucket. Panic ensues. You use adrenaline (fight-or-flight) to force your brain into gear.

The Cost: Living on a cycle of cortisol spikes is not sustainable. It is a leading cause of secondary anxiety diagnoses and adrenal fatigue in adults.^[5]

3. Rejection Sensitive Dysphoria (RSD)

Do you replay awkward conversations in your head for days? Does a slightly short email from your boss feel like a physical blow to the chest?

While not yet a standalone diagnosis in the DSM-5, Rejection Sensitive Dysphoria (RSD) is widely recognised by clinicians as a core aspect of adult ADHD emotional dysregulation.^[6] It is an extreme, often physical, emotional pain triggered by the perception of being rejected, criticised, or falling short of high standards.

Differentiation from Social Anxiety:

Social Anxiety: “I am worried they won’t like my work, so I will avoid them.” (Fear-based).
RSD (ADHD): “They didn’t like my work, therefore I am fundamentally flawed and the relationship is over.” (Shame-based flash reaction).

Rejection Sensitive Dysphoria (RSD) Mind Health Psychologists Sydney Parramatta — Rejection Sensitive Dysphoria (RSD)

4. The “Default Mode Network” Failure

When a neurotypical person finishes a task, their brain’s “Default Mode Network” (DMN)—the part responsible for daydreaming and background thought—quiets down to allow for rest.

Research indicates that in ADHD brains, the DMN fails to switch off effectively, even when attempting to relax.^[7] This results in a “noisy” brain or internal hyperactivity.

Thought A: I need to finish this report.
Thought B: I wonder if I paid the rego on the car?
Thought C: That car needs a wash.
Thought D: It’s raining. I love the smell of rain. Petrichor.

If you can rarely quiet your mind without exhaustion or substances (like alcohol), it may be hyperactivity manifesting internally as cognitive restlessness.

5. “Doom Piles” and Object Permanence

Look around your office or home. Do you have piles of paper, laundry, or random objects that you’ve stopped “seeing”?

This is often attributed to deficits in Working Memory and a struggle with Object Permanence (out of sight, out of mind).^[8]

The Mechanism: If you put a document in a filing cabinet, your brain worries it will cease to exist. So, you leave it out “just in case.”
The Result: Visual noise.

Eventually, your desk becomes a museum of unfinished tasks. The sheer executive load required to sort the pile feels physically painful, leading to avoidance behaviours often mistaken for laziness.

Doom piles and object permanence in ADHD

Next Steps: Clarity vs. Confusion

If you found yourself nodding along to these points, it’s possible you have been treating the symptoms (Stress/Anxiety) rather than the root cause (Neurodivergence).

The good news? You are not broken. You just have a different operating system. The first step to reclaiming your mental energy is an accurate, evidence-based diagnosis.

At Mind Health, our psychologists specialise in comprehensive Adult ADHD assessments that look beyond the surface level traits to understand your unique cognitive profile.

Ready to find out for sure?

Read: Learn about our Adult ADHD Assessment Process.
Meet: Check out our Team of Psychologists to find the right clinical fit for you.
Act: Contact Us to book an initial intake session at our Parramatta clinic or via Telehealth.

Stop guessing. Start thriving.

Frequently Asked Questions

Can you have both Anxiety and ADHD?

Yes. In fact, studies suggest that up to 50% of adults with ADHD also have an anxiety disorder. Often, the anxiety is a secondary coping mechanism developed to manage untreated ADHD symptoms (e.g., being anxious about time to avoid being late).

What is “High-Functioning” ADHD?

“High-functioning” is not a clinical diagnosis, but a term used to describe individuals with ADHD who mask their symptoms effectively in professional settings. They often achieve success through high intelligence or anxiety-driven overcompensation, but suffer from burnout and exhaustion in private.

Do I need a referral for an ADHD assessment at Mind Health?

No, you do not strictly need a referral to see a psychologist. However, to access the Medicare rebate for your sessions, you will need a Mental Health Care Plan from your GP.

References

Australian ADHD Professionals Association (AADPA). (2022). Australian Evidence-Based Clinical Practice Guideline For ADHD. Link
Dodson, W. W. (2016). Secrets of the ADHD Brain. ADDitude Magazine. Link
Volkow, N. D., et al. (2009). Motivation deficit in ADHD is associated with dysfunction of the dopamine reward pathway. Molecular Psychiatry, 16(11), 1147–1154.
Barkley, R. A. (1997). Behavioral inhibition, sustained attention, and executive functions: Constructing a unifying theory of ADHD. Psychological Bulletin, 121(1), 65–94.
Katzman, M. A., et al. (2017). Adult ADHD and comorbid disorders: clinical implications of a dimensional approach. BMC Psychiatry, 17(1), 302.
Bedrossian, A. P. (2021). Understand and address complex presentations of ADHD in adults. Current Psychiatry, 20(4).
Sonuga-Barke, E. J., & Castellanos, F. X. (2007). Spontaneous attentional fluctuations in impaired states and pathological conditions: A neurobiological hypothesis. Neuroscience & Biobehavioral Reviews, 31(7), 977–986.
Baddeley, A. (2000). The episodic buffer: a new component of working memory? Trends in Cognitive Sciences, 4(11), 417-423.

Bulent Ada

Bulent is a Sydney-based psychologist and author with 20+ years of experience in psychology and mental health. Founder of Mind Health (formerly Life Psychologists), he takes an integrative approach to psychotherapy, blending traditional therapies with cutting-edge methods.

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