Understanding Chronic Stress and Your HPA Axis

There’s something called the ‘H-P-A-axis’, which is helpful to understand in order to appreciate the impact of stress on your body, physically, cognitively and emotionally.

‘Axis’ basically means connection or coordination, and in this case I am referring to a line of communication between your brain and your adrenal glands.

H = the hypothalamus (the control centre of the brain)
P = the pituitary gland in the brain
A = the adrenal glands; two small glands that sit on top of your kidneys

Anything that is a gland releases hormones and the hormones released by the adrenals are adrenaline and cortisol, in response to threat or stress.

This is known as the body’s “fight or flight” stress response, which is designed to provide the body and brain with the energy and cognition it needs to fight or flee from a threat, which in our caveman days would have been a sabre toothed tiger.

The “Fight or flight” response is also known as sympathetic nervous system activation. The opposite of this is “rest and digest” mode, which is when the parasympathetic nervous system is activated.

The problem we have today for our health is that modern day stress DOES NOT require us to fight or flee, but the brain and body don’t know the difference between a genuine threatful situation that we DO need to flee from and a worry about a sick loved one for example. Now, many of us are chronically in a state of stress when the stress response was only meant for acute, few and far between stress or threat.

Modern day stressors / threat are MANY, here are some examples:

  • Being unhappy
  • Having too much on, never ending to-do lists, always saying yes, overcommitting
  • Too much high intensity cardio workouts or workouts that work against your biology
  • Dysfunctional relationships / relationship issues
  • Scrolling on social media
  • Watching / reading / listening to the news
  • Worries about loved ones
  • Work pressures
  • High alcohol consumption
  • Poor sleep
  • Always switched on / connected online
  • Feelings of loneliness or hopelessness
  • Critical self talk
  • Negative mindset
  • Running late / rushing
  • Poor diet (e.g., nutrient depleted, high sugar, refined carbs, processed foods, stimulants)
  • Financial worries
  • Major life events (operations, illness, bereavement, having a child, moving house etc)
  • Focusing too much on the future or past
  • Rigid thinking, lack of flexibility

FYI, the adrenal glands also make the body’s supply of DHEA, which is an androgen hormone along with testosterone. DHEA is used to make testosterone and if the adrenal glands are always too busy making the stress hormones, they make less DHEA, and therefore also less testosterone.

As part of the “fight or flight” response, adrenaline is released into the bloodstream first, to provide an instant flood of energy/fuel to the heart, brain and muscles so they can fight or flee from the problem. Shortly afterwards, cortisol is released to help us sustain the fight or flight response for a little bit longer.

Once the stressor (e.g. the sabre-toothed tiger) is out of the way, adrenaline levels return to normal after about 20 minutes and elevations in cortisol will remain in the system for about a day before returning to normal levels. Then, we shouldn’t need the stress response to be activated again for a long time – ideally and as was the case historically.

However, in our modern world many people are facing stressors and threats chronically (e.g. chronically sad or unhappy / busy / poor diet / dysfunctional relationships / financial concerns / rising cost of living / pandemics / big life events).

This puts people into a state of chronic stress, with a chronically activated “fight or flight” response. Over time, chronically elevated levels of cortisol take its toll on the body and mind and the H-P-A-axis becomes dysregulated. Once H-P-A-axis dysfunction is at play, chronically high levels of cortisol soon become chronically low levels of cortisol.

H-P-A-axis dysfunction has a very significant impact on sex hormones (production and how well they are broken down after use), thyroid hormone production, metabolism, mood, energy, sleep, inflammation, brain health, immunity, heart health and more.

Symptoms and situations from chronically elevated cortisol:

  • Sleep disruption / insomnia / sleep no longer restorative / ‘tired but wired’
  • Poor memory, poor decision making, trouble focusing, brain fog
  • Low energy and fatigue, especially in afternoon/evening
  • Chronic inflammation (which might cause joint pain, muscle aches + pains, headaches, brain fog, fatigue, trouble losing body fat)
  • Always on “high alert”
  • Increased anxiety
  • Suppressed / low immunity
  • Hormonal imbalances (sex hormones, thyroid hormone, growth hormones) including no ovulation in your cycles resulting in no progesterone being made
  • Digestive issues
  • Belly fat and increased visceral fat
  • Raised blood pressure

Symptoms and situations from chronically elevated cortisol:

  • Fatigue, particularly on waking
  • Low mood, depression, low motivation, anxiety, poor resilience, low tolerance.
  • Chronic inflammation (which might cause joint pain, muscle aches + pains, headaches, brain fog, fatigue, trouble losing body fat)
  • Low blood pressure, faintness or dizziness when getting up from lying or sitting down

The HPA axis is an important and empowering concept to understand. Once you understand the MANY types of stress in our modern world and it’s impact on this axis AND the axis’s impact on your health, you can start to take empowered action!

Inside my Thrive Through Perimenopause Online Course, we cover this in much greater detail. If you know now is the time for you to start addressing your nutrition and lifestyle habits to help optimise your health and hormones then join us! There are two options, a self study + Facebook group option or the live, more supportive option which includes weekly (small) group coaching calls with me alongside the course content and Facebook group. Click here to learn more and to join! If 1-2-1 support is a better fit for you, click here to learn more about how I work and the options.

Hi, I'm Francesca

I’m a Registered Nutritional Therapist who helps womens in their 40s find vibrant health and vitality, and thrive through perimenopause and beyond.

With nearly 10 years of experience working with hundreds of people, I empower and support women to support their bodies and hormones for a smooth and happy ride in their 4os.

Through our work together, clients have improved their energy, their periods and cycles, their mood, sleep, brain fog and digestion, and learned how to better manage their weight.

I am here to help you get back to YOU so you can have a fantastic time in your 40s.

My signature nutrition and lifestyle coaching approach to supporting women with their health and wellbeing is refreshing, down-to-earth and realistic.

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