Anxiety isn’t always caused by stress or mental health conditions alone. Physical factors like hormonal imbalances, nutrient deficiencies, and environmental toxins can also trigger anxiety symptoms.
Most of us have felt anxious at some point. For many, anxiety comes in response to life’s challenges—tight deadlines, tough conversations, unexpected changes. But what happens when anxiety seems to appear out of nowhere, or lingers despite therapy or self-care?
At Meru Health, we take a whole-person view of mental health. Anxiety is not always just “in your head.” Sometimes, it’s rooted in underlying physical, hormonal, or even environmental factors—many of which are commonly overlooked.
Here’s a look at some lesser-known causes of anxiety symptoms. Taking a more integrated view of health may help you find relief.
1. 🧠 Hormonal imbalances and anxiety
Hormones play a central role in emotional regulation. When they’re out of sync, your nervous system can stay stuck in a heightened, anxious state.
Thyroid issues: Both hypothyroidism and hyperthyroidism can cause anxiety, mood swings, and restlessness. (1, 2)
Perimenopause and menopause: Fluctuations in estrogen and progesterone can impact GABA (a calming neurotransmitter), increasing anxiety levels. (3, 4)
Cortisol dysregulation: Chronic stress can throw off cortisol rhythms, making you feel “wired but tired” and easily overwhelmed. (5)
2. 🍽️ Some nutrient deficiencies can trigger anxiety
Just like a car can’t run without fuel, your brain can’t function properly without key nutrients.
Some common deficiencies linked to anxiety include:
Magnesium – calms the nervous system and helps regulate stress response. (6)
Vitamin B12 and folate – essential for neurotransmitter synthesis; low levels can contribute to mood dysregulation. (7)
Omega-3 fatty acids – support brain health and reduce inflammation, which can exacerbate anxiety. (8)
🧠 Want to dive deeper into this topic?
Read our post: Most Common Nutrient Deficiencies and Their Impact on Mental Health
3. 💊 How medications and stimulants affect anxiety
Surprisingly, some prescription or over-the-counter medications may cause or worsen anxiety.
Common culprits include:
Steroids (e.g., prednisone) (9)
Thyroid medications (especially if dosed too high) (10)
Excessive caffeine intake (11)
4. 😴 The link between sleep disorders and anxiety
Sleep is essential for emotional regulation. When disrupted, your brain’s ability to process stress is impaired.
Insomnia and sleep apnea are both strongly linked to anxiety and panic symptoms. (12)
Poor sleep increases amygdala activity—the brain’s fear center—making you more reactive and anxious during the day. (13)
5. ⚠️ Can heavy metals and toxins fuel anxiety?
One of the most overlooked contributors to anxiety is exposure to heavy metals—particularly lead, mercury, cadmium, and arsenic—commonly found in industrial pollutants, contaminated water, or even older household materials.
What the research says:
A 2024 review in Frontiers in Public Health shows that heavy metal exposure can alter the gut-brain axis and trigger neuroinflammation, both of which are strongly associated with anxiety and depression. (14)
Lead exposure, even at low levels, has been linked to neurocognitive dysfunction and heightened stress reactivity, especially in those with early-life exposure. (15, 16)
Chronic low-grade inflammation triggered by environmental toxins can contribute to psychiatric symptoms. (17)
6. 🦠 Viral infections and long-term anxiety risks
Though still under study, there is evidence that some viruses may activate immune responses that contribute to long-term changes in mood and cognition.
Viruses such as Epstein-Barr, HSV-1, and cytomegalovirus have been linked to mood changes, anxiety and depression symptoms and neuroinflammation. (18, 19, 20, 21)
These infections may alter neurotransmitter systems, influence cortisol balance, and leave behind immune “scars” that elevate anxiety risk. (22)
7. 🧬 The gut-brain axis and its role in anxiety
Your gut and brain are in constant communication via the gut-brain axis—a network of nerves, hormones, and immune signals.
Imbalances in the gut microbiome (dysbiosis) can affect mood, especially via the production of neurotransmitters like serotonin (70–90% of which is produced in the gut). (23, 24)
Conditions like irritable bowel syndrome (IBS) or chronic bloating are often correlated with heightened anxiety. (25)
Recent research even connects environmental toxins—like heavy metals—to disruption of the gut-brain axis. (26)
The Meru Health perspective: Anxiety is multi-dimensional
Anxiety is never just one thing. That’s why our 12-week, clinically validated program takes a multidisciplinary approach, blending therapy, nutrition guidance, mindfulness, sleep support, and medical evaluation when needed.
Whether your anxiety is rooted in life stress, biology, or a complex mix of factors, you deserve a plan that sees, and treats, you as a whole person.
Interested in personalized support for anxiety?
📲 Explore the Meru Health program or take our brief assessment to see if it’s a fit for you.
References
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Lekurwale, V. et al. (2023a) ‘Neuropsychiatric manifestations of thyroid diseases’, Cureus [Preprint]. doi:10.7759/cureus.33987.
Mu, E., Chiu, L. and Kulkarni, J. (2025) ‘Using estrogen and progesterone to treat premenstrual dysphoric disorder, postnatal depression and menopausal depression’, Frontiers in Pharmacology, 16. doi:10.3389/fphar.2025.1528544.
Gilfarb, R.A. and Leuner, B. (2022) ‘GABA system modifications during periods of hormonal flux across the female lifespan’, Frontiers in Behavioral Neuroscience, 16. doi:10.3389/fnbeh.2022.802530.
Adam, E.K. et al. (2017) ‘Diurnal cortisol slopes and mental and physical health outcomes: A systematic review and meta-analysis’, Psychoneuroendocrinology, 83, pp. 25–41. doi:10.1016/j.psyneuen.2017.05.018.
Boyle, N., Lawton, C. and Dye, L. (2017) ‘The effects of magnesium supplementation on subjective anxiety and stress—a systematic review’, Nutrients, 9(5), p. 429. doi:10.3390/nu9050429.
Liwinski, T. and Lang, U.E. (2023) ‘Folate and its significance in depressive disorders and suicidality: A comprehensive narrative review’, Nutrients, 15(17), p. 3859. doi:10.3390/nu15173859.
Kiecolt-Glaser, J.K. et al. (2011) ‘Omega-3 supplementation lowers inflammation and anxiety in medical students: A randomized controlled trial’, Brain, Behavior, and Immunity, 25(8), pp. 1725–1734. doi:10.1016/j.bbi.2011.07.229.
Alturaymi, M.A. et al. (2023) ‘The association between prolonged use of oral corticosteroids and mental disorders: Do steroids have a role in developing mental disorders?’, Cureus [Preprint]. doi:10.7759/cureus.37627.
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