Adrenocorticotropic Hormone (ACTH)

Adrenocorticotropic Hormone (ACTH) is produced by the pituitary gland, a small but powerful gland at the base of the brain that coordinates many hormonal systems.
Its main role is to stimulate the adrenal glands, located above the kidneys, to release cortisol — the hormone that helps regulate stress response, blood pressure, metabolism, and immune function.

ACTH levels rise and fall throughout the day, following a natural circadian rhythm: highest in the early morning to help you wake up and lowest at night as your body prepares for rest. Because of this close relationship with cortisol, ACTH is often tested alongside cortisol to assess adrenal and pituitary health.

ACTH is a critical biomarker for understanding how well the brain and adrenal glands communicate — a central part of the body’s stress and energy regulation system known as the hypothalamic-pituitary-adrenal (HPA) axis.

• High ACTH levels may indicate that the pituitary is overworking to stimulate cortisol production, as seen in Addison’s disease, Cushing’s disease, or chronic stress.
  

• Low ACTH levels may signal that the pituitary is under-active (secondary adrenal insufficiency) or that cortisol levels are too high and suppressing ACTH through negative feedback.
  

Because ACTH directly influences cortisol and other adrenal hormones, it affects energy, mood, metabolism, immunity, and blood pressure, making it an essential marker for identifying hormonal imbalances or stress-related dysfunctions.

ACTH levels can vary due to stress, sleep, diet, and underlying hormonal feedback between the pituitary and adrenal glands.

Dietary Factors:

• Increase ACTH: High-sugar or refined carbohydrate diets cause blood sugar fluctuations and stress the adrenal axis.

• Support balance: Diets rich in protein, healthy fats, and fiber stabilise blood sugar and promote balanced cortisol production.
  

Lifestyle Factors:

• Increase ACTH: Chronic stress, sleep deprivation, and overtraining.

• Lower ACTH: Mindfulness, restorative sleep, and regular physical activity help normalise HPA axis function.
  

Related Biomarkers:

• Cortisol and aldosterone are directly regulated by ACTH.

• DHEA-S and renin may also shift with adrenal stress or insufficiency.
  

Micronutrient Impacts:

• Magnesium, vitamin C, vitamin D, and B vitamins support healthy adrenal and pituitary function.
  

Environmental Influences:

• Chronic psychological stress, toxins, and endocrine-disrupting chemicals (like BPA and phthalates) can dysregulate ACTH and cortisol secretion patterns.
  

If ACTH is High

Elevated ACTH often reflects overactivation of the stress response or insufficient cortisol feedback to the pituitary.

Diet

• Focus on a low-glycemic, anti-inflammatory diet rich in whole foods.

• Include complex carbohydrates (sweet potatoes, quinoa), lean proteins, and healthy fats (avocado, olive oil, nuts) to stabilise blood sugar and reduce adrenal stress.

• Avoid refined sugars, excess caffeine, and processed foods, which spike cortisol and worsen HPA imbalance.
  

Lifestyle

• Prioritise stress management — meditation, gentle yoga, or time in nature.

• Maintain a consistent sleep schedule (7–9 hours nightly) to restore hormonal rhythm.

• Incorporate moderate-intensity exercise such as walking, swimming, or Pilates — avoid overtraining, which can heighten ACTH and cortisol output.

• Limit alcohol and nicotine, as they increase stress hormones.
  

Supplements

• Omega-3 fatty acids (1–2 g/day): Support HPA axis balance and reduce inflammation.

• Vitamin D3 (2,000 IU/day): Supports adrenal and immune regulation.

• Magnesium (200–400 mg/day): Reduces cortisol output and promotes relaxation.
  

If ACTH is Low

Low ACTH suggests the pituitary is not adequately stimulating the adrenal glands, or cortisol levels are suppressing ACTH via feedback inhibition.

Diet

• Eat regular, balanced meals to support steady blood sugar and energy levels.

• Include healthy fats (olive oil, nuts, eggs), lean proteins, and complex carbohydrates (brown rice, lentils).

• Avoid long fasting periods or skipping meals, which can lower adrenal output.

• Ensure adequate electrolyte intake (sodium, potassium, magnesium) to support adrenal function.
  

Lifestyle

• Engage in gentle physical activity and avoid high-intensity exercise until energy improves.

• Prioritise restorative sleep and stress reduction to restore pituitary-adrenal communication.

• Reduce stimulant intake (e.g., caffeine), which can temporarily mask fatigue but worsen hormonal suppression.
  

Supplements

• Multivitamin with B-complex: Supports energy metabolism and hormone production.

• Vitamin C (500–1,000 mg/day): Nourishes adrenal glands and supports cortisol synthesis.

• Magnesium (200–400 mg/day): Supports pituitary-adrenal signaling and relaxation.

1. Annane, D., Pastores, S. M., Rochwerg, B., et al. (2017). Guidelines for the Diagnosis and Management of Critical Illness-Related Corticosteroid Insufficiency (CIRCI) in Critically Ill Patients. Critical Care Medicine, 45(12), 2078–2088. https://doi.org/10.1097/CCM.0000000000002737
   

2. Fleseriu, M., Hashim, I. A., Karavitaki, N., et al. (2016). Hormonal Replacement in Hypopituitarism in Adults: An Endocrine Society Clinical Practice Guideline. Journal of Clinical Endocrinology & Metabolism, 101(11), 3888–3921. https://doi.org/10.1210/jc.2016-2118
   

3. Bornstein, S. R., Allolio, B., Arlt, W., et al. (2016). Diagnosis and Treatment of Primary Adrenal Insufficiency: An Endocrine Society Clinical Practice Guideline. Journal of Clinical Endocrinology & Metabolism, 101(2), 364–389. https://doi.org/10.1210/jc.2015-1710
   

4. Beuschlein, F., Else, T., Bancos, I., et al. (2024). Diagnosis and Therapy of Glucocorticoid-Induced Adrenal Insufficiency. Journal of Clinical Endocrinology & Metabolism, 109(7), 1657–1683. https://doi.org/10.1210/clinem/dgae250