Hormonal Health and the Nervous System
A personal exploration of the endocrine system, the vagus nerve and evidence-informed naturopathic care.
By Sarah · Bachelor of Health Science
Research checked 15 September 2026
There is something I want to say before we talk about cortisol, menstrual cycles or the vagus nerve. You do not have to make your exhaustion sound more impressive before it deserves attention. You do not have to reach the point of falling apart to ask for care.
I am writing this as a woman, a mum and a passionate naturopath. Those parts of me belong in the same conversation. I care about the research, and I care about what happens when health advice meets a real household, interrupted sleep, work, money worries and people who need you.
Perhaps you recognise the loneliness of getting through the day while quietly wondering why ordinary things feel so difficult. Perhaps you love your family deeply and still wish, sometimes, that nobody needed anything from you for a little while. Perhaps you feel ashamed of how easily you cry, how little patience you have left, or how far away your own needs seem.
Loving your life and finding parts of it painfully hard can coexist. You should not have to edit out the difficult parts to be seen as a good mother.
This article explores how our hormonal and nervous systems communicate, what recent human research tells us, and where herbs and naturopathic care may offer useful support. It brings selected 2025 and 2026 studies together with older foundational research. It is a detailed journal article, rather than an exhaustive systematic review of every endocrine condition or publication.
My hope is that understanding some of the biology helps you describe what you need more clearly, without giving you another set of rules to fail at.
Understanding the endocrine system
The endocrine system is a network of glands and hormone-producing tissues. Hormones carry messages that influence growth, metabolism, reproduction and mood. The hypothalamus and pituitary in the brain help coordinate much of this activity; the thyroid, adrenal glands, pancreas and ovaries have different, interconnected jobs. Hormone function also changes with age, pregnancy, illness and medicines. [1]
When we say “hormonal health”, we often mean our periods. But insulin is a hormone. So are cortisol and thyroid hormones. This helps explain why a useful consultation might explore energy, appetite, temperature sensitivity and sleep alongside cycle changes. A symptom does not tell us which hormone, if any, is responsible.
Healthy hormones are not meant to stay at one perfectly even level. Timing matters. Reproductive hormones vary across the menstrual cycle and life stages; other hormones follow daily rhythms. A useful question is whether a pattern is appropriate for your circumstances, and whether symptoms suggest something that needs investigation.
This is why I am careful with the phrase “balance your hormones”. It can sound reassuring while leaving the actual problem undefined. I want us to be able to name what we are investigating and what improvement would look like for you.
Stress and the conversation between brain and body
One important communication pathway is the hypothalamic–pituitary–adrenal axis, usually shortened to the HPA axis. In response to a stressor, signals travel from the hypothalamus to the pituitary, then to the adrenal glands, which release cortisol. Feedback signals help adjust that response.
Cortisol is essential. It helps maintain energy availability and supports normal physiological functioning. It is not a toxin to remove, and lowering it is not automatically a sign of better health. Stress responses vary with the kind of stress, its duration, sleep, illness and the person experiencing it.
Alongside this hormonal pathway, the autonomic nervous system adjusts functions such as heart-rate and digestion. Its sympathetic and parasympathetic branches work in changing combinations. Being activated when you need to respond is normal; being calm all the time is neither realistic nor the goal.
You might recognise feeling physically tired while your attention keeps searching for the next task. That description matters, but it does not diagnose high cortisol or a damaged nervous system. Similar experiences can accompany anxiety, sleep deprivation, thyroid problems and other conditions. A clinician needs to listen and investigate rather than assign a hormone label from a symptom list.
“Adrenal fatigue” is not an established medical diagnosis, and there is no validated test for it. The symptoms people describe under that label can be very real. They deserve assessment for recognised conditions, including sleep disorders, depression or adrenal insufficiency where clinically suspected. Replacing the label with “HPA dysfunction” without appropriate evidence does not solve that problem. [2]
As a naturopath, I want my language to leave you more informed. You should understand the reason for a recommendation, rather than feel frightened that your body has stopped working.
Why menstrual symptoms can affect how we feel
The brain and reproductive system communicate in both directions. Changes in ovarian hormone signalling can affect how some women experience mood and daily functioning. The relationship is more nuanced than “too much oestrogen” or “not enough progesterone”.
Premenstrual dysphoric disorder, or PMDD, is one example. Research supports an unusual sensitivity to normal hormone changes in susceptible women; hormone concentrations do not have to be abnormal for the symptoms to be severe. Foundational NIMH research helped demonstrate this biological sensitivity, including responses when ovarian hormones were suppressed and then reintroduced. [4]
If you feel markedly different before your period, that pattern deserves to be taken seriously. A brief daily record of mood, sleep and symptoms over at least two cycles can help a clinician distinguish a recurring premenstrual pattern from symptoms present throughout the month. Severe depression or distress needs help immediately; you do not need to finish a diary first.
Stress and inadequate energy availability can also disrupt reproductive signalling. Functional hypothalamic amenorrhoea is a recognised condition in which periods stop in association with factors such as undernutrition, exercise and stress, after other causes have been excluded. Care focuses on the relevant contributors, including adequate nutrition and psychological support when appropriate. A missing period should not simply be treated with a “cycle support” supplement. [3]
These are different clinical situations. One universal hormone protocol cannot sensibly address them both. Nor can it replace assessment for conditions such as thyroid disease or polycystic ovary syndrome.
Motherhood deserves more than being told to rest
Pregnancy and the postnatal period involve substantial hormonal changes. Perinatal depression has multiple contributors, including biological vulnerability, life stress and the demands surrounding pregnancy and birth. It is a treatable health condition, not a measure of how much a woman loves her baby. Talking therapies, practical support and medication can all be part of care. [5]
What matters to me as a mum is how we make that care possible. Who can come over? Who can take a task from beginning to end? Who can listen without asking you to be grateful before you are allowed to be honest?
Advice to prioritise sleep can feel heartbreaking when you are already desperate for it. A plan needs to account for feeding, night waking, work and the support that is actually available. Sometimes the most useful first intervention is a conversation about sharing the load.
I also want to make space for the woman who is functioning well enough that nobody notices. She may still be struggling. Getting dressed, meeting deadlines and caring for children do not tell us whether someone feels safe or well inside.
Persistent low mood, frightening changes in thinking, severe anxiety or difficulty functioning after birth deserve professional assessment. Confusion, hallucinations or delusional beliefs after birth are an emergency. An herbal product or relaxation routine is not an adequate response to those symptoms. [5]
Perimenopause and the nervous system
The years around menopause can bring changes in sleep, mood and temperature regulation. Symptoms are variable, and care should consider the whole clinical picture. Hormone therapy and nonhormonal treatments can be appropriate options depending on symptoms, medical history and preferences. A naturopathic approach can sit alongside that discussion. [6]
A recent example of the brain–hormone connection comes from OASIS 3, a 2025 trial of elinzanetant, a medicine targeting neurokinin receptors involved in menopausal symptoms. The trial randomised 628 postmenopausal women and followed treatment for 52 weeks. At week 12, the adjusted difference favoured the medicine by about 1.6 fewer moderate to severe hot flushes or night sweats each day compared with placebo. [7]
Sleep and quality of life measures also numerically favoured treatment, but those analyses were descriptive; the trial was not designed to confirm those differences statistically. Treatment related adverse events were more common with the medicine, including sleepiness, fatigue and headache. This study illustrates a specific therapeutic pathway, rather than proving that all menopausal symptoms come from nervous system dysregulation. [7]
For me, the encouraging part is that women have options worth discussing. Choosing medical treatment does not undermine your interest in natural health. Your wellbeing matters more than loyalty to a particular category of treatment.
Sleep is part of hormonal care
In a small randomised crossover study published online in 2023 and in Diabetes Care in 2024, researchers studied 38 women. Restricting sleep by approximately an hour and a half a night for six weeks impaired insulin sensitivity. The finding helps connect everyday sleep loss with metabolic function, although the study was small and does not predict an individual woman’s future health. [8]
Insulin helps the body manage glucose. This is one reason a discussion about hormonal health should extend beyond reproductive hormones. Sleep belongs in that discussion even when weight has not changed.
Please do not read this as another reason to panic after a difficult night. A research finding describes a pattern under study conditions. It is not a forecast that a mother with an unsettled baby is destined to become unwell.
The useful question is where we can create more opportunity for rest, and whether a sleep problem needs specific treatment. Being kept awake by caregiving is different from lying awake despite having the chance to sleep. Loud snoring, breathing pauses and marked daytime sleepiness also deserve medical assessment.
What the vagus nerve actually does
The vagus nerve connects the brainstem with organs in the chest and abdomen. It carries sensory information towards the brain and signals outwards that help regulate functions including heart-rate and digestion. It is one important part of the wider autonomic system.
This communication helps explain why emotional and bodily experiences can feel closely linked. But the vagus is not the only pathway connecting the brain and body. Hormonal signals, immune activity, other nerves and the gut’s own nervous system also contribute.
“Vagal tone” refers to ongoing vagal influence; in research, cardiac vagal activity is often inferred from particular measures of heart-rate variability. It is not a single whole-body wellness score. A change in cardiac regulation does not establish that digestion, reproductive hormones and psychological wellbeing have all changed together. [9]
I understand the appeal of a simple explanation when you have felt overwhelmed for a long time. Being told there is one nerve you can fix offers a sense of control. You deserve an explanation that is both hopeful and accurate.
What heart-rate variability can and cannot tell us
Heart rate variability, or HRV, describes variation in the timing between heartbeats. Some measures can provide information about parasympathetic influence on the heart under suitable recording conditions. The 2024 psychophysiology publication guidelines emphasise careful measurement and physiological interpretation. [9]
Breathing, posture, age, medicines, recording conditions and data quality can affect results. A wearable reading is an indirect estimate, and a low reading alone cannot diagnose trauma, hormonal dysfunction or a “dysregulated” nervous system. Nor does a temporarily higher value prove that a treatment has repaired anything. [9]
If tracking feels useful, bring patterns to a qualified clinician alongside symptoms and context. If it makes you check repeatedly for reassurance, it is reasonable to step back. You do not need a device to give you permission to acknowledge that you are exhausted.
Breathing practices and the evidence behind them
A 2023 randomised study compared five minutes a day of structured breathing with five minutes of mindfulness meditation over a month. Breathwork, particularly an exhalation-focused practice called cyclic sighing, showed greater improvement in positive mood and a reduction in breathing rate. The study did not establish a cure for anxiety disorders, corrected reproductive hormones or lasting whole-body vagal changes. [10]
This is still a useful finding. An accessible practice can be worth considering without being presented as a complete treatment. The particular breathing methods in a trial also matter; we should not assume every practice sold as breathwork has the same evidence.
For a gentle everyday pause, you might sit with your feet supported and let your breath move comfortably, allowing the out breath to be a little longer if that feels easy. Begin briefly. There is no need to take enormous breaths or force a slow rate. This is a comfort practice, not a reproduction of the research protocol.
If focusing on breathing makes you dizzy, panicky or more distressed, stop. You could instead look around the room, feel the chair supporting you, or take a comfortable walk. A practice should be adapted to you. Struggling with meditation is not evidence that you are doing recovery badly.
What the newest vagus nerve research really shows
An important recent study, published online in December 2025 and in Nature Medicine’s January 2026 issue, investigated an implanted vagus nerve stimulation device for rheumatoid arthritis. RESET RA enrolled 242 people whose condition had responded inadequately to, or who could not tolerate, certain advanced medicines. At three months, 35.2% receiving stimulation met the trial’s ACR20 improvement threshold, compared with 24.2% receiving sham stimulation. [11]
This provides clinical evidence for a specific application of nerve stimulation in an inflammatory disease. It involved an implanted medical device, specialist care and surgical risks. It does not establish that humming, cold showers or consumer ear devices produce comparable effects, and it did not test treatment of hormonal symptoms. [11]
Noninvasive stimulation is an active research area, but devices, stimulation settings and the conditions studied differ. A positive result in one setting should not be converted into a universal “vagus reset” claim.
Humming or singing can still be enjoyable ways to pause. Enjoyment is a sufficient reason to do something. We do not need to claim that a pleasurable ritual is treating inflammation or restoring hormones for it to have a place in our lives.
I would not recommend buying a stimulation device from a broad wellness promise alone. The relevant questions are what exact condition it has been studied for, whether the device and protocol match the research, and who can assess its suitability for you.
Why herbal medicine matters to me
I am drawn to herbal medicine because it invites careful attention to plants, preparation and the person receiving them. There is something deeply meaningful about taking time with a cup of tea or a familiar evening ritual. That personal meaning can sit alongside a clear understanding of what clinical research does and does not show.
A study of a standardised extract is evidence about that preparation, in that population, at that dose and duration. It does not automatically apply to a tea, essential oil, different extract or multi-herb blend. “Natural” also does not mean suitable for every person.
The following studies are reasons for thoughtful clinical conversations. They are not a shopping list or instructions for self prescribing.
Saffron and recent research in women
A June 2026 randomised placebo-controlled trial studied 86 women aged 50 to 70 with low mood and poor sleep. Participants received a specific saffron extract, 28 mg daily, or placebo for 12 weeks. The study’s predefined meaningful improvement in depressive symptom scores occurred in 48.8% of the saffron group and 25.6% of the placebo group. [12]
Self esteem and sleep related daytime impairment also improved more with saffron, but those findings were exploratory. Sleep disturbance itself did not significantly improve compared with placebo. The manufacturer funded the trial and contributed to its initial concept and design; the investigators reported conducting the analyses independently. Larger independent studies would strengthen confidence. [12]
An earlier 2021 trial in 86 perimenopausal women also reported benefits in psychological symptoms with a particular saffron extract over 12 weeks. These are encouraging findings about symptoms in specific groups. They do not show that saffron universally corrects hormone concentrations or replaces assessment and treatment for depression. [13]
Ashwagandha and the difference between feeling better and changing a marker
A 2026 eight week trial randomised 141 adults with stress and anxiety to a proprietary ashwagandha preparation, another root extract or placebo. The proprietary preparation performed better on several self reported stress, anxiety and mood outcomes. Cortisol fell in all three groups, including placebo, so a within group fall alone cannot establish an herb specific effect. [14]
The broader research includes promising short term findings for stress and sleep, but studies differ in their extracts and participants. We need stronger information about long-term effects and who benefits most. A result in stressed adults does not make ashwagandha a treatment for every reproductive or thyroid concern. [15]
Safety changes the decision. Ashwagandha can affect thyroid function and interact with medicines; pregnancy and breastfeeding are reasons to avoid it. Australia’s TGA has also warned about severe gastrointestinal reactions and a very rare potential risk of liver injury. A history of liver problems is a reason to avoid it. Stop use and seek medical advice for warning signs such as yellowing skin or eyes, dark urine or significant abdominal symptoms. [15] [16]
Vitex for a specific premenstrual pattern
Vitex agnus castus, also called chaste tree, has research relating to premenstrual symptoms. In a foundational 2001 placebo-controlled trial, 170 women were evaluated over three cycles. A reduction of at least half in symptoms occurred in 52% receiving the studied extract and 24% receiving placebo. [17]
This older trial is included because it is relevant, not because it is new. It supports further consideration of a defined preparation for PMS; it does not establish Vitex as a universal fertility, menopause or progesterone treatment. Safety and suitability require review, particularly with hormone sensitive conditions, pregnancy, breastfeeding or medicines that may interact. [18]
The clinical question comes first: does this woman’s symptom pattern resemble the one studied, and have we considered other explanations?
Lavender and why the preparation matters
A 2014 trial involving 539 adults with generalised anxiety disorder investigated a standardised oral lavender oil preparation called Silexan. It reported improvement in anxiety symptoms compared with placebo. [19]
That finding concerns a manufactured medicinal preparation intended for oral use. It is not permission to swallow aromatherapy essential oils, and it does not prove that a lavender roller or diffuser treats an anxiety disorder. A pleasant fragrance may belong in a personal ritual without inheriting the claims of an oral medicine trial.
Chamomile and a more measured kind of hope
In a 2016 trial, people whose generalised anxiety had initially improved while taking chamomile extract were randomised to continue it or receive placebo. Continued treatment was associated with lower anxiety symptoms, but the reduction in relapse risk was not statistically significant. That distinction matters: the trial did not definitively establish prevention of relapse. [20]
Chamomile tea can still be a comforting choice if it suits you, but it is not equivalent to the studied extract. Allergies are possible, particularly with sensitivity to related plants, and interactions and pregnancy or breastfeeding suitability need consideration. Evidence for treating insomnia remains limited. [21]
I can value the quiet of making tea while being honest about the limits of the research. Those two things do not compete.
What working with a naturopath can offer
What I value most about naturopathic care is the opportunity to put the details together with someone. A careful consultation can explore the timeline of symptoms, nutrition, sleep, menstrual history, medicines, emotional wellbeing and the practical circumstances of daily life.
The benefits depend on the quality of the practitioner and the care offered. Research on an individual herb does not prove that every naturopathic programme works, or that naturopathy is superior to conventional care. My enthusiasm belongs with accountable, collaborative practice.
A thoughtful naturopath can help translate information into a manageable plan. If you are eating very little during a demanding day, nutritional adequacy may deserve attention before another supplement. If symptoms cluster around your period, tracking and appropriate assessment may clarify the pattern. If a prescribed medicine or existing supplement could be contributing, that deserves discussion with the prescriber or pharmacist.
Herbal knowledge can be particularly useful when it includes botanical identification, extraction methods, interactions, contraindications and a realistic appraisal of evidence. Sometimes careful herbal practice means choosing one suitable preparation. Sometimes it means choosing none.
I also believe there is value in having someone help you decide what does not need doing. You should be able to ask what a test would change, how a supplement might help, what it costs and when we would stop it. More testing is not automatically more thorough care.
Follow up gives the plan somewhere to go. Are you sleeping better? Are symptoms less disruptive? Can you function more comfortably? Are there adverse effects? If a plan is not helping, it should be reconsidered, rather than expanded indefinitely.
Good care also recognises its limits. GP assessment, psychological support, a dietitian, a gynaecologist or an endocrinologist may be needed. Coordinating with those professionals is a strength. I want women to feel supported in using the care that fits their needs.
A starting point that fits a real life
If you feel overwhelmed by everything you have read, begin with the concern that is affecting you most. You do not need to overhaul your entire routine this week.
You could write down when the symptom began, what it feels like and what it stops you doing. If it seems cyclical, note the timing. Bring that information, your medicines and your supplements to an appointment. A short, useful record is enough; it does not need to become another daily obligation.
Look at food through the lens of nourishment. What would make it easier to eat adequately and regularly? A prepared lunch, an accessible snack or someone sharing meal preparation may be more useful than restrictive rules. Where undernutrition is affecting menstrual function, restoring adequate energy availability is a clinical priority. [3]
Look at rest through the lens of opportunity. Is there a task you can stop doing, a night time responsibility that can be shared, or a sleep symptom that needs assessment? “Go to bed earlier” may not address the actual barrier.
Choose one practice you find comfortable: a brief breathing pause, gentle movement, time outside or a quiet moment with someone you trust. You do not need to describe it as a hormone intervention. Notice whether it helps you, and let that guide the conversation.
Finally, name a specific form of help. “Can you take care of dinner on Tuesdays?” is easier to act on than “I need to manage my stress.” The person asking for support should not have to invent and supervise every detail of that support.
When symptoms need medical attention
Please arrange medical assessment for persistent or worsening fatigue, new menstrual changes, recurrent palpitations or symptoms that interfere with daily life. Bleeding after menopause needs assessment. Very heavy bleeding with dizziness, fainting or weakness needs urgent care. Chest pain, severe breathing difficulty or collapse are emergencies.
If you are experiencing thoughts of suicide or self harm, seek urgent support. If there is immediate danger, call 000 in Australia or go to an emergency department. Postpartum confusion, hallucinations or delusional beliefs also require emergency assessment. [5]
This article provides general education. Individual assessment matters, especially during pregnancy or breastfeeding and when combining herbs with medicines. Do not stop prescribed treatment because of something you read here.
The woman receiving the advice matters
The part of this work I feel most strongly about is very simple. I want the woman receiving the advice to remain visible inside it.
I do not want you to leave a conversation about health believing you need to become a different kind of woman to deserve to feel well. A woman who never feels overwhelmed. A mum who always responds gently. Someone with enough time and money to do every recommended thing.
There is room for the version of you who needs help making the appointment. The version who is sceptical because she has already spent money trying to feel better. The version who wants to be cared for without having to prove she has tried hard enough.
As a mum and naturopath, I want to hold both the science and that tenderness. I want to remain curious about what herbal medicine can offer, honest about what is uncertain, and willing to work alongside other professionals when that is what you need.
You are allowed to want a life that feels more comfortable in your body. You are allowed to ask for care before you have found the perfect explanation for why.
Sarah
Wild Wellness with Sarah
Research and further reading
Numbered links in the article correspond to the sources below. Recent trials are dated explicitly; older trials and guidance provide context. Trial findings apply to the preparations and populations studied.
1. Endocrine Society. Hormones and endocrine function. Patient resource, 2022.
2. Endocrine Society. Adrenal fatigue. Patient resource, 2022.
5. NIMH. Perinatal depression. Patient information.
6. NICE. Menopause identification and management. Guideline NG23.
18. NCCIH. Chasteberry usefulness and safety. Updated April 2025.
21. NCCIH. Chamomile usefulness and safety. Updated November 2024.