Stress is not just a feeling. It is a biochemical event that affects every system in your body.

From a functional medicine perspective, chronic stress is one of the most significant root drivers of long-term dysfunction. It alters hormonal signalling, immune resilience, metabolic stability and brain chemistry in ways that are often subtle at first, but build over time.

When stress becomes constant, the body shifts from adaptation to survival.

But most importantly… it is not just the stress itself that matters. It is how your body perceives it.

Perceived stress: why your experience matters

Perceived stress is your internal experience of pressure.

It reflects how able you feel to cope, rather than what is objectively happening around you. Two people can have the same workload, the same family demands and the same external pressures, yet their bodies respond very differently.

One feels stretched but capable. The other feels overwhelmed and exhausted.

Your brain is constantly scanning for safety. If it perceives that you are not coping, it activates a stress response. If it feels that you are supported and in control, the response is far more measured.

This is why stress is not just about what is happening in your life, but how your body is interpreting it.

How the brain and adrenal glands drive stress

The stress response begins in the brain and is carried out through hormones. Think of hormones as letters delivered by the postman – they come from one source yet are delivered to nearly every cell in the body to create an effect.

When your brain perceives a threat, it signals the adrenal glands, which sit just above your kidneys. These glands release cortisol and adrenaline, increasing alertness, raising blood sugar and preparing the body to respond.

In short bursts, this is helpful and protective and extremely effective in keeping us safe. The body only has one stress response, regardless of the trigger – essentially thinking that we are running away from the tiger.

However, when stress is ongoing or perceived as overwhelming, the adrenal glands are repeatedly stimulated. Over time, this can lead to dysregulated cortisol patterns, where the body struggles to switch off and recover.

This is often where symptoms begin to appear.

Cortisol and the cortisol awakening response

Cortisol follows a natural daily rhythm.

It should rise sharply within 30 to 45 minutes of waking, known as the cortisol awakening response, helping you feel alert, focused and ready for the day ahead. It then gradually declines, allowing your body to wind down in the evening.

When stress is ongoing, this rhythm becomes disrupted.

Cortisol may spike too high in the morning, leaving you anxious or jittery. It may stay elevated into the evening, making it difficult to switch off. Or it may flatten over time, leaving you feeling depleted and reliant on caffeine.

You might notice:

• Waking already feeling on edge
• Needing coffee to feel functional
• Energy dips mid-afternoon
• Feeling tired but unable to sleep

When cortisol loses rhythm, so do sleep, mood and energy. The best thing to do to help your rhythm is to get some sunshine within 60 minutes of waking to help with reseting the daily cycle. Just a five minutes outside can make a real difference to your stress levels.

The ‘progesterone steal’

Cortisol and progesterone share the same building blocks.

When stress is chronic, the body prioritises cortisol production over progesterone. This is often referred to as the “progesterone steal,” and it has a direct impact on hormonal balance.

Progesterone has calming, stabilising effects on the brain. When levels drop, the nervous system becomes more reactive and less resilient.

This can show up as worsening PMS, increased anxiety, disrupted sleep and more pronounced perimenopausal symptoms.

Stress does not sit in isolation. It reshapes the hormonal environment and how you feel within it.

Magnesium depletion under stress

Magnesium is one of the body’s key calming minerals.

It supports nervous system regulation, muscle relaxation, blood sugar balance and sleep quality. It is also involved in hundreds – yes more than three HUNDRED biochemical processes that keep the body functioning smoothly.

Under stress, magnesium is depleted more quickly and excreted at a higher rate.

This becomes problematic because magnesium is needed to regulate cortisol and support the nervous system. When levels drop, the body becomes more sensitive to stress and less able to recover.

You may notice:

• Muscle tension or tight shoulders
• Palpitations or a sense of internal restlessness
• Poor or broken sleep
• Increased anxiety or irritability

The very nutrient that helps you feel calm is often the one that is most depleted. Supplementing with this supplement is common in my clinic, but it’s important to choose one that will help. Check out this blog for more info on supplementing: Supplements… Do you have expensive wee?

Chronic stress as a root cause

Functional medicine recognises chronic stress as a core driver of systemic illness.

Persistent cortisol dysregulation fuels inflammation, suppresses immune function and disrupts hormonal balance. Over time, this can contribute to adrenal dysfunction, gut issues, fatigue and cognitive decline.

Many people reach a point where they describe feeling burnt out.

This is not simply tiredness. It is a system that has been under pressure for too long without adequate recovery. If you can work on changing only one thing, stress will make the biggest difference.

How stress shows up in real life

This is something I see often, particularly in women who are used to coping.

They are capable, organised and high-functioning, often managing work, family and everything in between. They have learnt to push through and keep going, even when their body is asking for support.

For some, this becomes clearer after an ADHD diagnosis, or perimenopause – which can actually be misdiagnosed for each other as so many of the symptoms are the same.

There is often a realisation that their brain has been working harder for longer, managing focus, stimulation and emotional regulation. Masking and overcompensating can create a sustained level of internal stress that goes unrecognised.

When they begin to understand this, it can feel both validating and relieving.

They realise they do not need to push harder. They need to support their body differently.

The wider impact on the body

When stress becomes chronic, its effects extend across multiple systems.

Hormonal and adrenal dysfunction can lead to disrupted sleep, inconsistent energy and increased fat storage around the abdomen. The body becomes less efficient at regulating itself.

Chronic inflammation develops quietly in the background, often showing up as digestive discomfort, joint aches or persistent fatigue that never quite lifts.

Immune function is suppressed, making you more susceptible to infections and slower to recover when you do become unwell.

Metabolically, stress drives blood sugar instability and insulin resistance, while also increasing blood pressure and cardiovascular strain. The body remains in a state of readiness, even when there is no immediate threat.

At the same time, neurotransmitters such as serotonin, dopamine and GABA become disrupted. This affects mood, motivation, focus and emotional regulation, often leaving people feeling unlike themselves.

Stress can be measured

Stress is not just something you feel. It is something we can assess.

Functional testing allows us to measure cortisol patterns across the day, giving a clearer picture of how your body is responding. We can also assess nutrient levels such as magnesium, vitamin C, zinc and B vitamins including B6, B12 and folate.

Markers of inflammation and gut health add further insight.

This moves the conversation from guesswork to understanding. When you can see what your body is doing, it becomes much easier to support it effectively.

The role of sleep in stress

Sleep is both affected by stress and a major driver of it.

When sleep is disrupted, cortisol regulation worsens, blood sugar becomes less stable and emotional resilience drops. Even a few nights of poor sleep can make everything feel harder and more overwhelming.

At the same time, high stress makes it more difficult to fall asleep and stay asleep.

Breaking this cycle is often one of the most important steps in restoring balance.

A simple way to calm your system

One of the most effective ways to support your nervous system is through your breath.

Your breathing pattern sends direct signals to your brain about whether you are safe or under threat. Slowing your breath, particularly your exhale, helps shift the body into a calmer state.

Try this for two minutes:

Sit comfortably and place one hand on your chest, one on your belly.
Inhale gently through your nose for a count of four.
Pause briefly.
Exhale slowly through the mouth for a count of six.
As you breathe out, soften your jaw and shoulders.

Longer exhales tell the brain that it is safe to downshift. This supports emotional regulation, focus and decision-making, especially during hormonally sensitive phases.

You are not trying to empty your mind.

You are simply allowing your body to catch up with itself.

The functional medicine approach to stress

Stress management is not about removing all pressure from your life.

It is about restoring regulation so your body can respond appropriately and recover effectively.

We start with testing to understand cortisol rhythms, nutrient status and underlying imbalances. This creates a clear and personalised starting point.

From there, we use targeted nutrition to stabilise blood sugar, reduce inflammation and support adrenal resilience. Food becomes a tool to support energy, mood and hormonal balance.

Lifestyle interventions focus on calming the nervous system through sleep, breathing, movement and creating space for recovery. These are not optional extras, but essential signals of safety.

We also look deeper at root causes, such as gut health, inflammation or hidden stressors within the body. When these are addressed, the overall stress load reduces.

A note on hormesis

Not all stress is harmful.

Short-term, controlled stressors such as strength training, cold exposure or certain forms of exercise can build resilience. This is known as hormesis.

The key difference is recovery.

When the body has time and support to recover, it adapts and becomes stronger. Without recovery, stress becomes depleting.

A final thought

When stress becomes constant, it reshapes the body from the inside out.

But when we restore rhythm, replenish nutrients and support the nervous system, the body responds quickly. Energy steadies, sleep deepens and mood becomes more balanced.

You feel clearer. Lighter. More in control.

And importantly, you begin to feel like yourself again.

Ready to feel more like yourself again?

If you recognise yourself in this, you are not alone.

Many of the people I work with are high-functioning and capable, yet quietly running on empty. What they often discover is that their body has been asking for support for longer than they realised.

Through a combination of functional testing, personalised nutrition and health coaching, we work together to restore balance and build long-term resilience.

This is not about quick fixes.

It is about helping you feel energised, calm, clear and able to enjoy your life again.

If you’re ready to explore this, you can get in touch to book a health discovery call.

Let’s understand what your body is telling you, and what it needs next.

Are you ready to feel amazing, look great and make energised your new normal?

Great! You’re in the right place. Schedule a complimentary health discovery call

If you’re interested in finding out more…

I have created an e-book going into more detail on the ADHD and perimenopause connection. My tech abilities will get there for this to be automatically sent to you(!), but for now, please email me, and I will send you a copy, and add you to my mailing list so you can receive other similarly helpful information now and then.

Take a look at my other blogs and my hormone imbalance page on my website.