Updated 07/09/2023
“How much do you know about the HPA Axis?” I asked Tina when she told me how stressful her life was, and how lousy she’d been feeling. Her confused look said it all – she had no idea what I was talking about! And she’s not alone – nearly every time I ask that question, I see the same look.
I think it’s vital that people hear about what stress does to their bodies. Almost every woman I’ve worked with has told me that their lives are a constant stream of stressors, large and small. When I express concern about the amount of stress they’re under, they shrug it off as if chronic stress is a normal and necessary part of the human experience. Few understand that this never ending stress could be causing the symptoms they’ve come to see me about.
More and more people are talking about stress, and it’s impact on the body, these days, and that’s great news. But that conversation is still missing far too often when visiting conventional medical practitioners. That’s partly due to the constraints of insurance billing codes and time limits (often, primary care doctors are scheduled so tightly they have less than ten minutes to spend with each patient), and partly because conventional physicians are trained to deal with disease. They’re looking for specific diagnoses. Unfortunately, adrenal dysfunction, the diagnosis that fits the myriad symptoms caused by chronic stress, is only recognized at two extremes.
Adrenal dysfunction (also called adrenal fatigue) is something I’ve talked a lot about. I’ve spent decades gathering information on how the adrenal glands work, how they impact health, and how to help women heal their adrenals naturally. Along the way, it’s become clear how few women have a true understanding of how their stress response works. While adrenal dysfunction is part of the issue, in reality the entire HPA axis is at the heart of the problem. But many women have never even heard of it!
With this article, I hope to change that. I’ll offer a brief overview of the parts of the HPA axis and what they do, what happens when this axis becomes dysregulated, and some simple steps you can take to calm your stress response and keep yourself healthy.
What is the HPA axis?
The Hypothalamic-Pituitary-Adrenal (HPA) axis is the interconnected relationship between several glands in the nervous and endocrine systems that secrete hormones essential to survival.
The primary function of the HPA axis is to help your body respond to stress. Here’s how it works:
The hypothalamus is a small neuroendocrine area in the brain, just above the brainstem. It is responsible for releasing hormones from the pituitary gland, which is just below the hypothalamus. These hormones enter the bloodstream and head to the kidneys, where they prompt the adrenal glands, which sit atop the kidneys, to secrete a range of hormones.
In times of stress, the hypothalamus releases corticotropin releasing hormone (CRH) which tells the pituitary gland to send adrenocorticotropic hormone (ACTH) to the adrenals. When the ACTH reaches the adrenals, it induces the release of cortisol, a primary “stress hormone”.
Cortisol causes your body functioning to change in response to this stress. Blood pressure increases and your muscles receive more blood, in case flight is required. Circulating glucose levels also rise, providing your body with extra energy to deal with the stressor.
Ideally, cortisol levels (and body functioning) return to normal when the source of stress has passed. Unfortunately, when stress is ever present, your body assumes it needs more cortisol, and levels in the blood often remain too high. High cortisol levels inhibit some processes, like reproduction, that are less important to survival.
That’s fine in the short term – who is thinking about sex when a wild animal is chasing them? But when it becomes the norm, eventually the high cortisol levels will create a negative feedback loop, shutting down the stress response. This can lead to hormonal imbalances that cause a variety of serious symptoms.
Another important factor is the ratio of DHEA to cortisol. In testing, cortisol levels can appear normal, but the DHEA:cortisol ratio will indicate a dysregulated HPA axis.
What happens when your HPA axis becomes dysregulated?
Both high and abnormally low levels of cortisol impact the HPA axis. In order to adequately deal with stress, this axis should be functioning properly. If it’s overstimulated or understimulated, it will become dysregulated – and both extremes lead to a wide range of undesirable health conditions.
An overactive HPA axis can lead to both physical and psychological problems. People with chronically high cortisol levels may have a suppressed immune response which makes them more vulnerable to infection. Research has shown that high cortisol has been linked to obesity, cardiovascular disease, and type 2 diabetes, negative impacts on cognition and memory, and mood disorders. Other conditions related to hyperactivity in the HPA axis include anorexia nervosa, obsessive compulsive disorder, panic disorders, alcoholism, and hyperthyroidism.
On the flip side, low activity in the HPA axis can lead to conditions like adrenal insufficiency, chronic fatigue syndrome, fibromyalgia, depression, post-traumatic stress disorder in adults, rheumatoid arthritis, asthma and eczema, to name just a few.
As you can see, there are a lot of good reasons to keep your HPA axis functioning optimally. And the good news is, there are some simple things you can do to make sure this axis is healthy. It’s all about reducing stressors through lifestyle choices.
Tips for Reducing Stress and Keeping Your HPA Axis Calm
Despite what you may hear from conventional medical professionals, a prescription is not the best way to address the issue of chronic stress. Medication simply masks the symptoms — it’s a bandaid, not a cure. If you don’t pay attention to the source of the problem – the stressors you face daily – it’s unlikely anything will truly change. As soon as you stop taking the medication, symptoms are likely to flare up. And long term use of any prescription comes with the potential for serious side effects.
I know that changing habits isn’t easy. It takes commitment and a real understanding of why you should change your lifestyle. That’s why I try to offer some natural, simple changes (instead of saying “Change everything, right now!). Every little step you take can add up to balanced activity in the HPA axis and you feeling fantastic! Try the following tips to get started:
Keep blood sugar stable with a healthy diet
I’m sure you’ve heard plenty of reasons to eat healthy, but may not have ever considered a poor diet a source of stress. Your body does, though! Long term instability of blood glucose levels certainly contributes to inflammation and cortisol production. Some easy ways to stabilize blood sugar include avoiding added sugars as much as possible; eat plenty of fresh fruits and vegetables, healthy fats, and fiber; eat at regular intervals; avoid processed foods and high carbohydrate choices; and increase phytonutrients with vividly colored vegetables, spices, and herbs.
Skip the caffeine
What, no coffee? So many women tell me that’s impossible – and you might just need a cup in the morning to get you going. But one cup is plenty, so after that, switch to decaf coffee, herbal tea, or water. Caffeine mimics the stress response, so your body needs a break!
Learn to say no to stress
There are many stressors that live outside our own control. And if you don’t know something is a stressor, you can’t make changes. But so many people fill their days with absolutely avoidable stress – and even wear it as a badge of honor sometimes! The person with the busiest calendar and most to do isn’t the winner – in fact, if this is you, you’re setting yourself up for a big crash. You don’t have to say yes to everything someone asks you to do. Examine your life and start by cutting out just one activity that makes you cringe when you think about it. Keep doing this until the only things left are those that you can get excited about!
Protect your sleep
We all know that sleep is essential – it’s obvious from the way we feel when we miss out on it! Getting poor sleep on a regular basis kicks your stress response into overdrive. Create a schedule that works for your life, but still builds in at least 7-8 hours of sleep. For instance, if you can’t get to bed early, don’t set your exercise routine for 5 am. Or if you wake up naturally at 4 am, head to bed an hour or two earlier so you can still get those 7-8 hours.
Get up and move
It may seem contradictory to move more if your body is already feeling stressed, but physical activity is vital to good health. Extreme sports aren’t a great idea if your HPA axis is already out of balance, but gentle movement like yoga, t’ai chi, or stretching can really help. If you love what you’re doing, moving will seem easy. So, get up and dance with your children, take a long walk after dinner, try a new fitness class, or hop on a bike and go for a ride.
Ensure adequate nutrient intake
A healthy diet is a great start, but sometimes it’s just not enough, especially when your HPA axis is overworked. Discuss your individual needs with a functional medicine practitioner and consider finding a supplement regimen designed especially for you.
After I told Tina about the HPA axis, and how much stress was impacting how she felt, she made it a point to begin clearing stressors from her life. She started having a salad with healthy protein for lunch every day, said no to a new volunteer request, and started a tap dancing class she’d always wanted to try. Little by little, she changed her habits (including stopping at one cup of coffee in the morning), and was amazed at the difference in how she felt. Just knowing what stress was doing to her made her able to make better choices for her health. You can do it too, and lead a healthier, low-stress life. Doesn’t that sound great?
Resources:
Chronic Stress and the HPA Axis:
Dunlavey CJ. Introduction to the Hypothalamic-Pituitary-Adrenal Axis: Healthy and Dysregulated Stress Responses, Developmental Stress and Neurodegeneration. J Undergrad Neurosci Educ. 2018;16(2):R59-R60. Published 2018 Jun 15.