Co-Occurring Conditions in Neurodivergence — An Overview © Patti O. Hedderly
If you’re neurodivergent and it feels like your body came with a whole bundle of physical and mental challenges attached, here’s the first thing to know: you’re not imagining it, you’re not “too sensitive,” and you’re not alone.
For many autistic people, and for people with ADHD, dyslexia, high sensitivity, or other neurological differences, a diagnosis is often just the opening chapter. What follows may include physical, immune, and mental health conditions that co-occur in patterns now recognized by doctors and researchers. What feels like a random, overwhelming list of separate diagnoses is often, in reality, a single interconnected web of biology, neurology, and psychology.
And here’s the good news: once you understand how the pieces connect, you gain real power. Small, steady care in one part of the web calms the whole system, which means the effort you put in doesn’t just help one symptom; it ripples outward and helps everything. That’s not a one-time fix; it’s a lifelong relationship with your own body, built from small, kind choices that compound into a life that feels more comfortable, more stable, and more truly yours. Attending to both mind and body, finding what is helpful, healing, or unhelpful, creates changes over time that let you live your best life, rather than chasing and depleting yourself in pursuit of some imagined version of “success and worthiness.”
It Starts in the Structure: Connective Tissue
The story often begins with connective tissue — the protein “scaffolding” that holds your skin, joints, blood vessels, and organs together. Many neurodivergent people carry genetic variations that shape how this scaffolding is built. That’s part of why Ehlers-Danlos Syndromes (EDS) and general joint hypermobility show up so often alongside neurodivergence.
If this is you, your joints aren’t weak, and you’re not overdramatic. Your body is built a little differently, and working with that difference rather than against it can improve your quality of life.
That looser, more pliable connective tissue affects more than joints. When blood vessel walls don’t hold their usual tone, your body has to work harder to push blood back up to your brain when you stand. Your heart compensates by racing, which can present as Postural Orthostatic Tachycardia Syndrome (POTS), one of the most common autonomic nervous system conditions (dysautonomia) among neurodivergent people.
None of this is a personal failing. It’s mechanics, shaped by genetics. And mechanics respond to care: hydration, gentle movement, compression garments, and pacing and calming yourself, practiced patiently over time, genuinely change how you feel day to day. This is one of the clearest payoffs in the whole picture — simple, low-cost habits with outsized, compounding returns.
The Immune Layer: Mast Cells and MCAS
Living inside that same connective tissue are mast cells, immune “sentinels” that release histamine and other inflammatory chemicals when they sense a threat. When the tissue around them is mechanically unstable, it places physical stress on these cells, causing them to fire too easily and too often. That’s Mast Cell Activation Syndrome (MCAS): chronic, unpredictable, allergy-like reactions that can touch almost any system in the body.
If you’ve ever been made to feel like you have “too many” sensitivities or reactions, there is real biology behind what you’re living with.
Asthma fits into this same picture. When mast cells throughout the body are primed to overreact, those same inflammatory signals can irritate the airways too, making respiratory sensitivity a natural companion rather than an unrelated coincidence.
Mast cells also sit right next to the nerves and blood vessels that regulate your autonomic (automatic) body functions. When MCAS floods your system with histamine, it can destabilize heart rate, disrupt digestion (IBS, Crohn’s), and make temperature regulation harder. Dysautonomia can worsen MCAS, and MCAS can worsen dysautonomia — a feedback loop sometimes called the “trifecta”: EDS, POTS, and MCAS. Some neurodivergent people experience all three fully; others have one clearly diagnosed condition while the others simmer in the background, milder but still present.
Here’s why this matters for how you take care of yourself: because this is a loop, not a straight line, calming any one part of it gives the whole system room to settle. You don’t have to fix everything at once; a little relief in one place echoes through the others. That’s worth pursuing patiently, for the long haul.
The Nervous System Layer: Feeling It All More Vividly
Neurodivergent brains often process internal body signals differently, and that’s not a flaw, just a different way of being wired (see Chapter 10 for a deeper look at interoception). Many neurodivergent people notice subtle internal sensations very vividly: a shift in heart rate, a change in digestion, the very first hint of tightness in the chest.
When inflammation is already present in the body, these signals can arrive more loudly and urgently, and a highly attuned nervous system can amplify the physical instability already underway. This isn’t anxiety being mistaken for physical symptoms. It isn’t physical symptoms being mistaken for anxiety. It’s both, woven together at the neurological level, and both deserve to be taken seriously.
Fibromyalgia and chronic pain are common companions here too, and they deserve the same patient, validating care as every other piece of this picture.
The Genetic Thread Running Through It All
Emerging research suggests that a shared cluster of genes may simultaneously shape connective tissue strength, immune response thresholds, and neuropsychiatric traits. In other words: the overlap between neurodivergence, hypermobility, immune sensitivity, and autonomic ups and downs likely isn’t a coincidence; it may be written into the genome itself. This is an active area of study, and the details will keep sharpening as more research is done.
There’s something genuinely validating in that. This is biology, not a character flaw, and it was never within your control to prevent. What is within your control is how gently and consistently you care for yourself from here forward, and that consistency is where the real payoff lives. This may run counter to what you learned in your family and culture. You have likely already paid a price in health, stress, or exhaustion for attempting to live according to those scripts. This is a challenge and a calling to find your own values and integrity so you can make the best choices for your body, heart, and mind.
Mental Health, Sleep, and the Gut
The emotional and psychiatric side of this picture is shaped by biology and by the world around you. Anxiety and depression can come not only from neurological wiring, but from the real, cumulative weight of navigating a world built around neurotypical expectations. That ongoing effort takes a genuine physiological toll. You’ve been responding honestly to a real demand, not overreacting to a small one.
Sleep threads through everything: circadian rhythm differences, insomnia, and trouble regulating melatonin are common in neurodivergent people (Chapter 8 covers this in depth). Poor sleep can then strain immune function, autonomic balance, and emotional resilience, which means protecting your sleep, even imperfectly, is one of the highest-leverage things you can do for your long-term wellbeing.
The gut-brain connection adds one more layer. Because the nervous and digestive systems are in constant two-way communication, neurological differences often show up as IBS, constipation, or food sensitivities. Eating differences like Avoidant/Restrictive Food Intake Disorder (ARFID) frequently come from sensory processing differences that make certain textures or smells genuinely intolerable not pickiness, not a choice, just real. And because dysautonomia can blunt interoception (your sense of what’s happening inside your body), a slight nausea or a dulled sense of hunger can mean that, at the end of the day, a neurodivergent person simply forgot to eat.
Navigating Care, One Gentle Step at a Time
Seeing these conditions as a single connected system, rather than a checklist of unrelated problems, can change both how you approach care and how much hope you carry into it.
Looking for professionals who understand the intersection of hypermobility, dysautonomia, and immune dysfunction (the trifecta) is often far more useful than seeing separate specialists who each only see one slice. Connective tissue and autonomic concerns are typically evaluated by specialized neurologists, cardiologists (especially electrophysiologists), or medical geneticists. Organizations like Dysautonomia International and the B4ND network on neurodivergence and MCAS can help connect you with providers who genuinely understand this picture.
Why the Small Things Are Worth It
This is a marathon, not a sprint, and that’s actually good news, because it means you don’t need a dramatic overhaul to feel the benefit. Self-care here isn’t a luxury or an indulgence; it’s the steady, lifelong practice of listening to your body, honoring what it needs, and treating yourself with the same patience you’d offer a dear friend.
The payoff is real, and it compounds: hydrating consistently eases POTS symptoms, calms mast cells, and takes pressure off an already-alert nervous system. Pacing your energy protects your joints, your sleep, and your emotional resilience. Every gentle, steady choice you make doesn’t just help one symptom, because your body is one connected web — that care spreads outward through the whole system.
Small, consistent choices: pacing your energy, prioritizing rest, staying hydrated, seeking out informed care, add up over years into a life that feels more livable, more comfortable, and more truly your own.
You are worth that care, today and every day after.
