For years, my work day would start with coffee and most days would end with wine.
In between, I worked 12-hour days, trained hard, ate "well" and got everything done. If you'd asked anyone who knew me, they'd have said I had it together.
What they didn't see was the stuff underneath. Skin that wouldn't clear no matter what I tried. Weight that wouldn't shift, even though I was eating well and exercising consistently. And a low, constant hum of never quite feeling like enough. Like if I stopped for a second, everything would fall apart.
I genuinely thought that was just who I was, but it wasn't. It was a dysregulated nervous system. And nobody had ever explained to me that nervous system regulation starts on your plate, and that what I was eating, and not eating, was a big part of why mine wouldn't switch off.
If you've landed here after Googling "nervous system regulation" at midnight, after the magnesium spray, the breathing app and the early night you didn't actually get, I want you to hear this: you're not broken, and this isn't a willpower problem. This is what high-functioning anxiety feels like from the inside. Everything gets done, but you're running hot the entire time.
So, here's what I wish someone had told me back then.
What Is Nervous System Regulation?
Nervous system regulation is your body's ability to move out of "fight or flight" (your sympathetic nervous system) and back into "rest and digest" (your parasympathetic nervous system) once a stressor has passed. A regulated nervous system still responds to pressure. It just doesn't get stuck there.
When that shift back down stops happening easily, you end up living in a low-level stress state most of the day. You can read more about the recovery side of this in my post on how the parasympathetic nervous system restores energy.
What Happens When Nervous System Regulation Breaks Down
When your nervous system is stuck in a heightened state, your body produces more cortisol than it needs to. Cortisol's job is short-term: mobilise energy so you can respond to a threat. The problem is a threat that never fully resolves, a deadline, an inbox, a household to run. Cortisol stays elevated, and it's not about willpower, and it's not about your workout. It's a body that thinks it's still under attack. (If you want the full picture on this hormone, read Understanding Cortisol: Symptoms, Belly Fat, and Testing.)
Blood sugar makes it worse. Skip breakfast, run on coffee, crash by 3pm, and you've just handed your nervous system another reason to stay on high alert. Erratic blood sugar and a dysregulated nervous system feed each other in a loop that no amount of extra effort breaks. Nervous system regulation is the actual lever, not another to-do list item.
I see this constantly with the ambitious professionals I work with: eating well on paper, exercising consistently, and still feeling tired but wired, because the piece nobody addressed was the stress physiology underneath it.
The Three Nutrients That Support Nervous System Regulation
Not all nutrients pull equal weight here. Three show up consistently in both the research and in clinical practice, and gaps in each are common, especially in busy, high-output lives.
Magnesium: the mineral most of us are quietly low in
Magnesium appears to support the brain's main calming neurotransmitter, GABA, and may help modulate the HPA axis, your body's central stress-response pathway. In plain terms: adequate magnesium helps your nervous system come back down instead of staying switched on.
The catch: chronic stress depletes magnesium, which makes nervous system regulation harder, which keeps stress elevated. It's a loop, and a diet heavy in processed food and light on plants makes it worse. Not sure if you're low? Here are 5 signs you might be magnesium deficient.
Food sources: leafy greens, pumpkin seeds, dark chocolate, legumes, almonds.
B vitamins: the fuel your brain and nerves run on
B6, B9 (folate) and B12 are all involved in keeping your brain chemistry running smoothly. B6 is needed directly to make serotonin, dopamine and GABA, while folate and B12 support the wider chemical processes these neurotransmitters depend on. B12 also helps maintain the protective coating around your nerve fibres that keeps signals travelling efficiently. Low levels of any of the three are linked in research with low mood, brain fog and a nervous system that's quicker to tip into "on."
Food sources: eggs, meat, oily fish, legumes, leafy greens. If you eat plant-forward, keep a close eye on B12 specifically.
Omega-3s: building resilience from the inside out
EPA and DHA get built directly into your brain cell membranes. They may reduce neuroinflammation and help buffer how your brain responds to stress signals, with the greatest benefit likely where intake is low. That's relevant here in the UK: guidance recommends at least one portion of oily fish a week, but national diet survey data shows most adults don't reach that.
Food sources: salmon, mackerel, sardines, walnuts, flaxseed. If you're considering supplementing, as always, quality and dosage matter, and it's worth working with a practitioner to get both right for you specifically.
The Gut-Brain Axis: Why Your Gut Is Central to Nervous System Regulation
The gut-brain axis is one of the most underrated levers in nervous system regulation, and it's not close.
The vagus nerve carries signals in both directions between your gut and your brain. Early research, mostly in animals so far, suggests your gut microbiome may influence vagal tone: essentially, your nervous system's ability to shift down from "on" into recovery.
Roughly 90% of your body's serotonin is made in your gut. It doesn't travel to your brain directly, but it shapes the signals your gut sends upward. Your microbiome also produces short-chain fatty acids and other compounds that may feed into gut–brain signalling.
Food sources that support this: diverse vegetables, oats, kefir, berries, extra virgin olive oil. These aren't extras. They're foundational to a nervous system that can actually regulate itself. (I share the ones I use myself in my favourite tools to improve gut health, energy and mental clarity.)
Nervous System Regulation Day to Day: What a Food-First Reset Looks Like
Not a retreat. Not a supplement stack. A nervous system reset is built from ordinary meals, repeated.
Blood sugar stability is the unglamorous engine behind all of this. A meal that spikes and crashes creates a physiological stress response even when nothing stressful is actually happening. Anchor every meal around protein, fibre, and fat, and you give your nervous system a far more stable environment to work from, morning through evening.
In practice: eggs on wholegrain toast with half an avocado instead of cereal or nothing. A grain bowl at lunch with tinned salmon, chickpeas, roasted veg, and olive oil. Neither is complicated. Both hold your blood sugar, and by extension your nervous system, steady. For more ideas that fit around a full diary, see my food habits that calm your nervous system at work.
A few other pieces of the reset that compound faster than people expect:
Hydration. Even mild dehydration may been linked to raised cortisol.
Alcohol. It disrupts HPA-axis function and fragments the sleep you need to actually recover overnight.
Ultra-processed food. Not a moral failing, just lower in the exact micronutrients your nervous system runs on, and it tends to crowd out the foods that provide them.
Eating consistently through the day, instead of under-eating and then stress-eating at 9pm, is one of the simplest structural shifts on this list, and one of the highest-leverage.
None of this requires restriction or a perfect week. Someone eating a magnesium-rich lunch four days out of five is doing more for their nervous system than someone who plans a flawless week and abandons it by Wednesday.
Why High-Functioning Anxiety Needs a Personalised Nervous System Regulation Plan
If any part of this sounds like your version of high-functioning anxiety, you're not the only high-achiever sitting with it quietly.
Generic advice is true and useless at the same time. "Eat more greens" applies to almost everyone and helps almost no one specifically. What someone chronically under-slept and running high cortisol needs is not what someone well-rested and broadly healthy needs. Your absorption, your blood work, your dietary history, and your actual stressors all change what you're short on, and why.
At Alison Diss Nutrition, the starting point is always that individual picture: relevant markers, dietary patterns, energy, and lifestyle context. From there, we build a food-first nervous system regulation plan that targets what your body is actually missing, not a generic template with your name on it. And if anxiety is affecting your day-to-day life, nutrition works best alongside support from your GP or a mental health professional.
One Thing Worth Busting: You Don't Need to Overhaul Everything
The instinct, once you know all this, is to change everything on Monday. Resist it.
Health isn't built through one big decision, it's built through the small choices we make every single day. Start with one meal. One nutrient. One honest look at what's actually been missing. Your body responds faster than you'd expect once you give it what it needs, and nervous system regulation happens in the compounding, not in the overhaul.
Nervous System Regulation FAQs
What are the signs of a dysregulated nervous system?
Common signs include feeling tired but wired, struggling to switch off at night, irritability, a 3pm energy crash, brain fog, sugar or caffeine cravings, and digestive issues. If symptoms are severe or persistent, check in with your GP to rule out other causes.
Can food really help with nervous system regulation?
Food isn't the only lever. Sleep, movement, breathwork and support all matter. But what you eat shapes your blood sugar, your cortisol response and the nutrients your nervous system runs on, so it's one of the most consistent levers you have.
How long does nervous system regulation take?
It varies from person to person. Steadier blood sugar can change how you feel within days to weeks, while rebuilding nutrient levels and stress resilience usually takes longer.
Bringing It Home
A dysregulated nervous system isn't fixed with a breathing exercise in the moment it happens. It's built calm slowly, meal by meal, through magnesium, B vitamins, omega-3s, and a gut environment that supports healthy vagal signalling. Those aren't optional extras. They're the biological conditions that make nervous system regulation possible in the first place.
If you're ready to stop guessing and get a plan built around your actual physiology, start with a free 30-minute clarity call.
And if you already know you want the full picture, The Realign Method is where we build that plan properly over 6 months, starting with exactly this.
I work with professionals across Surrey, in Woking, Weybridge, Guildford, Cobham and West Byfleet, and online across the UK.
References
Pickering, G., Mazur, A., Trousselard, M., Bienkowski, P., Yaltsewa, N., Amessou, M., Noah, L., & Pouteau, E. (2020). Magnesium status and stress: the vicious circle concept revisited. Nutrients, 12(12), 3672.
Young, L. M., Pipingas, A., White, D. J., Gauci, S., & Scholey, A. (2019). A systematic review and meta-analysis of B vitamin supplementation on depressive symptoms, anxiety, and stress: effects on healthy and "at-risk" individuals. Nutrients, 11(9), 2232.
Su, K.-P., Tseng, P.-T., Lin, P.-Y., Okubo, R., Chen, T.-Y., Chen, Y.-W., & Matsuoka, Y. J. (2018). Association of use of omega-3 polyunsaturated fatty acids with changes in severity of anxiety symptoms: a systematic review and meta-analysis. JAMA Network Open, 1(5), e182327.
Breit, S., Kupferberg, A., Rogler, G., & Hasler, G. (2018). Vagus nerve as modulator of the brain–gut axis in psychiatric and inflammatory disorders. Frontiers in Psychiatry, 9, 44.
Yano, J. M., Yu, K., Donaldson, G. P., Shastri, G. G., Ann, P., Ma, L., Nagler, C. R., Ismagilov, R. F., Mazmanian, S. K., & Hsiao, E. Y. (2015). Indigenous bacteria from the gut microbiota regulate host serotonin biosynthesis. Cell, 161(2), 264–276.
Dalile, B., Van Oudenhove, L., Vervliet, B., & Verbeke, K. (2019). The role of short-chain fatty acids in microbiota–gut–brain communication. Nature Reviews Gastroenterology & Hepatology, 16(8), 461–478.
Alison Diss Nutrition
Alison Diss is a BANT Registered Nutritional Therapist, Personal Trainer and founder of The Realign Method. She created The Realign Method after her own experience of burnout in a high-pressure career and has helped 100+ ambitious professionals achieve steady energy, a sharper mind and a stronger body. She's based in Surrey and works with clients UK-wide and online.