While successful recovery from HPA-D necessitates a variety of lifestyle interventions, including adequate sleep and consistent stress-reduction practices, your diet is often overlooked in the context of HPA-D. However, it turns out that nutrition has far-reaching impacts on the HPA axis, and that following a strategic HPA axis dysfunction diet may accelerate your recovery. Read on to learn how you can use nutrition to support your HPA axis and a balanced stress response.
HPA axis dysfunction has far-reaching effects on your health, but nutrition (along with a variety of lifestyle interventions) can help you recover. Check out this article from nutritionist Lindsay Christensen for steps to following an HPA axis dysfunction diet. #nutrition
What Is HPA-D?
Before we dive into a discussion on how you can use nutrition to support a healthy stress response, it will help us to have a deeper understanding of the body’s stress response system and how it is connected with ancestral health.
The HPA axis is a network of endocrine organs, hormones, and other signaling molecules that serves as the body’s stress-response system. The HPA axis evolved to help our bodies respond efficiently to acute stressors, such as being chased by a lion, but research indicates that it is poorly equipped to handle the chronic stressors we face today.
Chronic activation of the HPA axis through continuous exposure to stressors can lead to HPA-D, or an inability of the HPA axis to effectively regulate the production of hormones and downstream systems such as the gut and brain. At least initially, HPA axis hyperactivation leads to high levels of cortisol, often considered the body’s primary stress response hormone. However, over time, HPA axis function can also bottom out, leading to low cortisol and depleted levels of a variety of other hormones, including estrogen, progesterone, testosterone, and dehydroepiandrosterone (DHEA).
Symptoms of HPA-D
I recommend hormone testing, such as the DUTCH Plus test, to look at your overall cortisol pattern and hormonal status. That being said, there are some symptoms commonly seen in either cortisol excess or depletion that may point you in the direction that your body is trending.
Excess cortisol symptoms include (please note that this is not a definitive list):
- Ovulatory issues
- Gut dysbiosis
- Leaky gut
- Irritable bowel syndrome
- Panic attacks
- High blood sugar
- Insulin resistance
- High blood pressure
Conversely, low cortisol levels may contribute to:
- Post-traumatic stress disorder
- Seasonal affective disorder
- Feeling less resilient than normal
- Chronic infections
- Brain fog
Systemically, HPA-D also alters levels of neurotransmitters. These molecules send signals from one neuron to another and are responsible for our mood, cognition, and heart rate. HPA-D often elevates catecholamines, a class of neurotransmitters that includes epinephrine, norepinephrine, and dopamine. It also elevates glutamate, the body’s primary excitatory neurotransmitter that can have toxic effects on the brain when it is too high. Conversely, HPA-D decreases gamma-aminobutyric acid (GABA), the body’s primary inhibitory and calming neurotransmitter, and lowers serotonin, often referred to as the body’s “feel-good” neurotransmitter.
The combination of hormonal and neurotransmitter perturbations triggered by HPA-D has far-reaching adverse effects on the body. It decreases the body’s overall resilience and metabolic reserve; impairs immunity; increases inflammation; and disrupts cognition, metabolism, and the gut microbiome. Chris has previously discussed HPA-D at length in his article “Adrenal Fatigue or HPA Axis Dysregulation?” and his podcast, “The Myth of Adrenal Fatigue.”
Seven Steps to Help You Follow an HPA Axis Dysfunction Diet
For long-term recovery, it is crucial that you address the underlying causes of your HPA-D, whether that’s a stressful lifestyle, a chronic infection, or gut dysbiosis. However, nutrition can also serve as powerful adjunct support in your recovery process. Here are seven steps to help you adopt an HPA-D diet.
1. Avoid Eating Processed, Refined Foods that Stress the HPA Axis
While chronic stress is a contributing factor in unhealthy eating behaviors, unhealthy eating behaviors may also perpetuate chronic stress via the HPA axis! A processed Western diet has been found to exaggerate the biological stress response in animals. These effects may carry over into stressed-out humans, as well. (1) Part of the problem may be that the Western diet is rich in high-glycemic-index (GI) carbohydrates, which have been found to elevate cortisol. (2) Therefore, the chronic consumption of these high-GI foods may lead to perpetually elevated cortisol, triggering a vicious cycle of chronic stress and unhealthy eating behaviors. (3)
2. Avoid Dieting
We live in a very diet-focused culture, where losing weight and looking good is often prized above all else, including actual physiological health! If you are suffering from HPA-D, you must eschew the restrictive diet culture and focus primarily on supporting your body with nourishing, nutrient-dense foods, as caloric restriction (and carbohydrate restriction) may exacerbate HPA-D. In fact, if you have HPA-D and are on a reduced-calorie diet trying to lose weight, your well-intentioned diet may have the opposite effect, causing you to put on additional body fat due to rising cortisol levels. (4)
If you are struggling with HPA-D and are confused about how best to feed your body, consulting with a nutritionist may help. A functional nutritionist or dietitian can help determine your ideal energy intake, macronutrient ratios, and micronutrient intakes that will best support your HPA axis and your whole body health.
3. Don’t Skimp on Carbohydrates, but Be Sure to Choose Nutrient-Dense Carbs
If you are struggling with HPA-D, it may not be the best time to cut your carbohydrate intake. Preliminary research suggests that low-carbohydrate and ketogenic diets may increase cortisol; long-term restriction of dietary carbohydrates could potentially lead to chronically elevated cortisol and subsequent HPA-D. (5) Low-carb diet advocates vehemently argue against this concept. While there is indeed some research suggesting that carbohydrate restriction may attenuate stress responsivity by reducing insulin signaling, there is also evidence to the contrary. (6)
However, one study also found that increasing carbohydrates, in the context of a whole-foods diet, reduces critical markers of stress responsiveness, including cortisol and cortisol responsiveness. (7) Anecdotally, I also find that many of my clients with HPA-D do better on a moderate-carbohydrate diet than a low-carb or keto diet. A moderate carbohydrate intake is defined as eating approximately 75 to 100 grams of carbs per day.
I’ve also observed that my female clients with HPA-D struggle more with low-carb and keto diets than men; this may be because estrogen, the primary female sex hormone, potentiates stress responsivity and may potentially make women more prone to HPA-D. (8)
If you want to experiment with adding more carbs to your diet to support your HPA axis, be sure to choose nutrient-dense carbs such as:
- Sweet potatoes
- Winter squash
- Whole fruit
You can also try incorporating small amounts of gluten-free grains or legumes if your body tolerates them well. Avoid refined carbohydrates, as these foods exacerbate blood sugar dysregulation, which has been found to potentiate the stress response.
To experience more benefits from an increased carb intake, consider trying carb back-loading. Carb back-loading is an eating practice in which you consume the majority of your carbohydrates with your evening meal, rather than spread throughout the day. This practice reduces blood sugar fluctuations over the day, which are harmful to HPA axis function. It supports the synthesis of serotonin and melatonin in the evening, which may enhance sleep quality.
4. Regulate Your Blood Sugar
Glucocorticoids, including the stress hormone cortisol, and glucose regulation are tightly linked. Fluctuations in blood sugar influence glucocorticoid secretion and metabolism, and vice versa. It is, therefore, unsurprising that blood sugar dysregulation has significant adverse effects on the HPA axis. (9) Keeping your blood sugar within a healthy range over the course of each day (and night) may, thus, aid in your recovery from HPA-D.
There are several steps you can take nutritionally to improve your blood sugar control. The first step I suggest is to remove refined carbohydrates from your diet. Instead, focus on nutrient-dense, Paleo-friendly carbs such as sweet potatoes and whole fruit.
Dietary protein also positively influences glycemic variability, attenuating postprandial blood sugar fluctuations. A good starting point is to aim for at least four ounces of protein at each meal, or a serving of protein approximately the size of the palm of your hand. It is particularly important to eat plenty of protein at breakfast, as this may improve your glycemic control over the day. (10) Twenty to 30 grams of protein at breakfast may be ideal for attenuating blood sugar variability over the course of the day.
5. Support Your Gut Microbiome
Emerging research indicates that HPA-D has adverse effects on the gut microbiome. The gut microbiome, in turn, can influence the HPA axis and stress responsivity through the gut–brain axis. (11) Supporting your gut microbiome is, thus, crucial for helping your body restore healthy HPA axis function.
To support your gut microbiome, be sure to eat plenty of fermented foods. As Chris discussed is his article, “The 13 Benefits of Fermented Foods and How They Impact Your Health,” fermented foods are rich in a wide variety of probiotic species and other bioactive compounds with beneficial effects on the gut microbiome. Some of the probiotic bacteria identified in fermented foods have been found to exert beneficial effects on the gut–brain axis, which links up with the HPA axis. For example, several species of probiotic bacteria produce GABA, a neurotransmitter with calming, relaxing properties that is often depleted in HPA-D. (12) I suggest that you aim for at least one serving of fermented foods per day.
Be sure to eat plenty of prebiotic foods, including anthocyanin-rich blueberries and blackberries, onions, garlic, leeks, asparagus, bananas, and chicory root. These foods support the growth of beneficial gut bacteria.
6. Get Enough Micronutrients and Phytochemicals to Support a Healthy Stress Response
A variety of micronutrients and phytochemicals can help regulate the body’s stress response.
Vitamin C plays a central role in adrenal function, primarily by acting as a potent antioxidant within the adrenal glands. (13) Vitamin C is found in:
- Brussels sprouts
- Citrus fruits
If you need a more concentrated food-based source of vitamin C, camu camu berry and acerola cherry powders are good options.
Omega-3 Fatty Acids
Omega-3 fatty acids also appear to play a central role in HPA axis function. In humans, omega-3 fatty acid deficiency is associated with elevated levels of corticotropin-releasing hormone (CRH), a peptide hormone that stimulates production of adrenocorticotropic hormone in the pituitary gland, and, subsequently, cortisol production by the adrenal glands. Omega-3 fatty acid deficiency is also linked to elevated salivary evening cortisol. Elevated CRH and salivary evening cortisol are, in turn, associated with HPA-D. (14) Omega-3 fatty acid deficiency may, thus, create a vicious cycle of chronic inflammation and a heightened stress response, causing the HPA axis to go haywire.
Conversely, omega-3 fatty acid sufficiency may support a healthier, more resilient stress response by alleviating inflammation and improving heart rate variability, a measure of the variation in time between each heartbeat that is a useful metric for gauging the resiliency of one’s stress response.
In animal studies, omega-3-rich fish oil has been shown to alleviate HPA-D triggered by lipopolysaccharides, molecules produced by gram-negative bacteria that are correlated with gut dysbiosis and chronic inflammation. (15)
To bolster your omega-3 fatty acid levels and optimize your stress response, I recommend that you aim for three to four servings of wild-caught seafood per week. If this isn’t possible, omega-3 fatty acid supplementation through fish oil may be necessary.
Magnesium is an essential mineral for robust, resilient HPA axis function. Magnesium deficiency increases anxiety and HPA-D by amplifying the transcription of CRH. (16) Conversely, magnesium repletion may normalize HPA axis function by serving as a cofactor in the metabolism of catecholamines, neurotransmitters that are released during the body’s stress response.
Magnesium also raises brain-derived neurotrophic factor, a neuroprotective protein that is decreased in individuals with HPA axis hyperactivity. (17) Magnesium also reduces neuronal excitability at the N-methyl-D-aspartate receptor and enhances calming GABA neurotransmission. (18)
Foods rich in magnesium include:
- Dark leafy greens
- Pumpkin seeds
- Brussels sprouts
L-theanine is an amino acid analogue found in green tea that supports a balanced stress response. (19) In fact, the high intake of green tea by Buddhist monks has been theorized to contribute to their impressively calm demeanor and intense focus during meditation. You may need to drink upwards of three cups of green tea per day to consume enough L-theanine sufficient to impact your HPA axis. Be sure to choose an organic green tea to reduce your exposure to pesticides and other toxins, which have been found to disrupt the brain’s stress circuitry. (20)
Dark chocolate contains phytochemicals with beneficial effects on the salivary cortisol response. (21) Choose chocolate that contains at least 70 percent cacao and, if you are highly sensitive to caffeine, consider eating it earlier in the day rather than in the evening.
Holy basil is a medicinal plant with a long history of use in traditional Indian Ayurvedic medicine. Holy basil contains unique phytochemicals, ocimumosides A and B, that attenuate HPA axis hyperactivity by regulating the stress-response proteins CRH, proopiomelanocortin, and heat shock protein 70. (22, 23)
Licorice Root Tea
Finally, if you have HPA-D with low cortisol, licorice root tea may be beneficial because it helps normalize the balance between cortisol and cortisone, an inactive metabolite of cortisol. (24) If you are on any pharmaceutical drugs, be sure to consult with your doctor before trying licorice root tea, as licorice root interacts with a wide variety of medications.
7. Eat Mindfully
Mindful eating is defined as paying attention to an eating experience in the present moment, engaging all your senses, and noticing emotional and physical responses to your meal with curiosity and without judgment. You can integrate mindful eating seamlessly into your day by following a few simple guidelines:
- Sit down in a chair, at a table to eat, rather than eating while standing or on the go.
- Avoid watching TV, texting, and answering emails while eating.
- Give your body a few minutes to relax when switching from a stressful task or scenario (such as intense work) to mealtime.
- As you sit down and prepare to eat your meal, ask yourself a few questions:
- Where am I?
- What is going on around me?
- How do I feel at this moment?
- Am I really hungry?
- What am I thinking about?
- How does this meal make me feel?
These simple practices can have a profound impact on your eating experiences, and may make you feel calmer, more in tune with your body, and more nourished by your meal.