Calm FROM WITHIN: How Your Stress System Shapes Health (and how nutrition can help)

At FROM WITHIN, I often meet people who feel “wired and tired,” wake unrefreshed, ride waves of cravings and energy dips, or notice gut flare‑ups when life gets busy. Many have a sense that stress or past pressures are still echoing in the body. A helpful way to understand this is through your stress‑response network, especially the hypothalamic–pituitary–adrenal (HPA) axis, alongside a polyvagal lens that explains how the nervous system prioritises safety. This article keeps the science clear but practical, it outlines what the HPA axis does, how chronic stress can nudge it off‑rhythm, why that can show up in your gut, sleep, mood, and metabolism, and how evidence‑based nutrition and gentle lifestyle anchors can support you back toward steadier energy and resilience.

Meet your stress system: the HPA axis

The HPA axis is a communication loop between your brain and adrenal glands. In everyday life, it helps you respond to challenges, regulate energy and blood pressure, and keep inflammation in check. Cortisol, often labelled a “stress hormone”, is central to this system and follows a daily pattern: a healthy rise shortly after waking, then a gradual slide to its lowest levels at night so you can sleep (Adam & Kumari, 2009; Russell & Lightman, 2019). Short spurts of stress temporarily lift cortisol and sympathetic activity so you can focus and act, built‑in feedback then settles everything back to baseline (Sapolsky et al., 2000; Herman et al., 2016).

Trouble tends to arise when stress is relentless or unpredictable, or when recovery is scarce. Over time, the body accumulates “allostatic load”, the wear and tear from constantly adapting (McEwen & Stellar, 1993; McEwen, 1998). In some people this shows up as persistently high cortisol or a flattened day‑night rhythm; in others, the response becomes blunted, especially after long periods of overdrive (Fries et al., 2005; Adam & Kumari, 2009). These shifts don’t happen in isolation, they interact and impact sleep, immune function, appetite signals, and digestion.

A polyvagal perspective: why stress feels so physical

Polyvagal theory offers a compassionate framework for how your body navigates safety and threat (Porges, 2011). Rather than a single “stress mode,” your autonomic nervous system moves between three broad states. In a calm, connected ventral vagal state, digestion, repair, and clear thinking thrive. When challenges arise, sympathetic activation helps you mobilise. If overwhelm feels inescapable, a dorsal vagal shutdown can conserve energy, which may feel like numbness, fatigue, or fog. None of these states is “good” or “bad”, they’re all adaptive, but being stuck in defence can leave digestion unsettled, sleep fragmented, and energy unpredictable. Viewing symptoms through this lens helps us pace change, layer in cues of safety, and create conditions where your body can spend more time in the steady state where healing lands best (Porges, 2011; Cryan et al., 2019).

Dysregulation of the HPA axis: allostatic load and burnout

Burnout, which is commonly described as emotional exhaustion, reduced effectiveness, and a sense of detachment, often reflects a system that has been coping for too long without adequate recovery (Maslach & Leiter, 2016). Research links chronic psychosocial stress and burnout with altered cortisol rhythms, autonomic imbalance, and a constellation of physical and emotional symptoms (Salvagioni et al., 2017; Adam & Kumari, 2009). You might notice any combination of the following: disrupted or light sleep, headaches or muscle tension, increased aches or infections, gut sensitivity or reflux, heightened anxiety or low mood, heavier afternoon fatigue with late‑night second winds, or changes in appetite and weight. While everyone’s pattern is personal, the common thread is that stress biology is spilling into daily function.

The gut–brain–immune axis: why you feel stress in your gut

Your gut and brain are in constant conversation via nerves (including the vagus), hormones, and immune signals. Stress can change gut motility (speeding e.g., diarrhoea, or slowing transit e.g, constipation), increase intestinal permeability, and activate mucosal immune cells, effects that can heighten sensitivity to foods and gas (Vanuytsel et al., 2014; Konturek et al., 2011). It can also shift the microbiome and its metabolites, influencing mood and pain perception through the gut–brain axis (Mayer et al., 2015; Cryan et al., 2019). This is why periods of high demand can make you feel both mentally stretched and physically uncomfortable and why a calm nervous system and a well‑nourished gut often go together.

How nutrition support helps—without adding overwhelm

My role as a certified practising nutritionist (CPN) is to turn complex science into a plan that feels doable and kind to your nervous system. We start by taking a thorough case history: assessing your stress and sleep patterns, energy curve, mood, menstrual or thyroid symptoms, medications and supplements, caffeine and alcohol, pain and gut symptoms, and your overall food pattern. We screen for red flags that warrant medical review and collaborate with your GP on sensible baseline labs where appropriate (for example, iron studies, B12/folate, vitamin D, a thyroid panel, and basic metabolic markers). If cortisol rhythm testing is considered, we will look at functional testing.

From there, we focus on foundations that support HPA balance and vagal tone. A Mediterranean‑style pattern - think colourful plants, extra‑virgin olive oil, nuts, seeds, legumes, whole grains, and quality proteins, supplies the fibres, polyphenols, omega‑3s, magnesium, and B vitamins associated with better cardiometabolic health and lower inflammation, and it’s been linked with improved mental health outcomes in several studies (Estruch et al., 2013; Lassale et al., 2019; Jacka et al., 2017). We steady blood glucose with regular, satisfying meals built around protein, fibre‑rich carbohydrates, and healthy fats; balance glucose curves, which often translate to steadier mood and energy. If your gut is sensitive, we tailor fibre choices and portions, gradually building tolerance so you can nourish your microbes without flares. Selected probiotics may be appropriate in some cases, but they’re introduced one at a time and monitored, because benefits are strain‑specific and modest on average (Didari et al., 2015; Kato‑Kataoka et al., 2016; Messaoudi et al., 2011).

We also pay attention to the everyday habits that signal safety to your body. Simple pre‑meal pauses, for example, a few slow breaths, can improve digestive comfort by engaging parasympathetic pathways. Consistent sleep‑wake times and morning daylight help restore circadian rhythm, which in turn supports cortisol patterns, appetite regulation, and metabolic health (Scheer et al., 2009). Movement is chosen for enjoyment and recovery, not punishment: walking, gentle strength work, yoga, or other activities that become a habit. Stimulants and sedatives are used thoughtfully, for example, caffeine timed after breakfast rather than on an empty stomach, and alcohol kept away from bedtime, because both can disrupt sleep depth and raise next‑day stress reactivity (Lovallo et al., 2005).

Importantly, none of this is about restriction for restriction’s sake. The goal is to create predictability and nourishment so your stress system can re‑learn safety. We keep changes as small as possible, protect pleasure in food, and collaborate with your medical team or therapist when trauma, anxiety, depression, perimenopause, thyroid issues, sleep apnoea, or other factors are in the mix (Porges, 2011; Danese & McEwen, 2012). Progress tends to feel like fewer flares, more restorative sleep, a more stable energy curve, and a sense that your body is easier to live in.

Why choose FROM WITHIN?

There’s a lot of information online about stress, hormones, and “adrenals,” and it can be overwhelming. At FROM WITHIN, you get a personalised, evidence‑based treatment plan that fits your life and respects your nervous system. We prioritise the least restrictive, most effective steps; we protect your nutrition; and we make sure you don’t have to navigate this alone. If you’re curious whether stress biology is part of your symptoms—and you want a clear path forward—book a consult with me here, and let’s map out what your body needs to feel calm, nourished, and resilient again.

Recipe:

Why this helps the HPA axis

• Salmon provides omega-3 fats (EPA/DHA) that help reduce inflammation and support brain function.

• Sweet potato and greens supply magnesium and B vitamins, important for energy and stress response.

• Avocado and seeds add healthy fats and minerals (magnesium, zinc) that support adrenal function and hormonal balance.

• Garlic and ginger bring anti-inflammatory compounds and flavour without added sugars.

• Balanced protein, fat, and fibre help steady blood sugar, which supports a more stable cortisol response.

Adrenal-Nourishing Salmon Quinoa Bowl (serves 2–3)

Ingredients

2 salmon fillets

1 cup quinoa, rinsed

2 cups bone broth or water

1 large sweet potato, cubed

2 cups broccoli florets

2 cups kale or spinach, chopped (or a kale and spinach salad mix)

1 avocado, sliced (if in season)

1/4 cup pumpkin seeds or walnuts

2 tablespoons extra-virgin olive oil (divided)

1 lemon (zest + juice)

2 cloves garlic, minced

1 inch piece fresh ginger, grated

Salt and pepper

Optional garnish: chopped parsley or coriander, sesame seeds (black & white)

For the dressing

2 tablespoons extra-virgin olive oil

1 tablespoon lemon juice

1 teaspoon Dijon mustard

Instructions

1. Preheat oven to 200°C. Line a baking sheet with baking paper

2. Roast vegetables:

o      Toss sweet potato cubes with 1 tablespoon EVOO, salt, and pepper. Spread on the sheet and roast for about 20 minutes.

o      Add broccoli to the sheet (drizzle with a little more EVOO, salt, pepper) and roast another 12–15 minutes, until tender and lightly caramelised.

3. Prepare quinoa:

o      In a pot, bring broth or water to a boil. Add quinoa, reduce heat, cover, and simmer about 15 minutes until fluffy. Fluff with a fork, stir in half the lemon zest and a pinch of salt.

4. Cook salmon:

o      Pat salmon dry. Rub with the remaining EVOO, garlic, lemon zest, salt, and pepper.

o      Place on a separate sheet pan and bake 12–15 minutes, or until the fish is opaque and flakes easily.

5. Prep greens and dressing:

o      While everything cooks, toss kale and spinach with a squeeze of lemon juice and a pinch of salt to soften slightly.

o      In a small bowl or jar, whisk or shake together dressing ingredients.

6.  Assemble bowls:

o      Start with a base of quinoa. Top with roasted sweet potatoes and broccoli, sautéed greens, and salmon.

o      Add avocado slices and a sprinkle of pumpkin seeds or walnuts.

o      Drizzle with the lemony dressing and garnish with parsley or coriander and sesame seeds if desired.

References

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