The cortisol reset Stress & Sleep

The cortisol reset

7 min read


Many people with cortisol dysregulation (often known as hypercortisolaemia) describe a familiar, frustrating pattern: you drag through the morning, feel exhausted by midday, yet your mind is on overdrive come evening; sleep is a nightmare, you wake unrefreshed, and, if it wasn’t enough, fat accumulates around your middle. This is also known as 'tired but wired' and is often associated with low mood, cravings and energy crashes, and difficulty switching off at night, symptoms that make daily life harder.

The 24-hour cortisol rhythm 

Cortisol follows a predictable 24-hour rhythm. In healthy people, cortisol rises sharply on waking (high cortisol is what wakes you up in the morning and helps you get out of bed), then gradually declines through the day to reach its lowest concentration late in the evening (typically 11.00 PM), which supports sleep and overnight repair.

What a healthy cortisol curve looks like

Ideally, you have a sharp cortisol awakening response (CAR) within 30–45 minutes of waking. You feel alert throughout the morning, then, as cortisol levels lower throughout the day, you feel tired as melatonin levels rise, and eventually fall asleep.
Cortisol_Levels___Dysfunction.1.png

What dysregulation actually means

Dysregulation often shows as a flattened or inverted curve: low or blunted cortisol on waking (explaining morning fatigue and difficulty rising) and relatively higher cortisol in the evening (explaining the racing mind and poor sleep). Someone who is 'high cortisol' or 'low' all day is not the same as someone with an inverted rhythm. Interestingly, people with constantly 'high cortisol' can become 'low cortisol' over time as it exhausts the body's resources due to chronic hyperactivation of the stress response.

Morning reset 

Morning light within 30 minutes of waking

Natural light is among the most powerful regulators of the circadian system. Getting daylight exposure within 30 minutes of waking helps anchor the cortisol (and melatonin) peak to the correct time. The best way to do that is to stand by an open window or step outside for 5–20 minutes. If you have a pet, this is the perfect time to go for a short walk.

Protein at breakfast

A protein-rich meal helps stabilise blood glucose and prevent stress responses associated with hypoglycaemia. Aim for whole-food proteins such as eggs, tofu, Greek yoghurt, or nut butter with plenty of fibre. Think linseeds, chia seeds and hemp seeds, among other fibre-rich foods. This supports steadier cortisol and energy across the morning.


No screens for 30 minutes after waking

You’ve probably been told to avoid devices before bed. Still, notifications, checking emails, and emotional content trigger a stress response that can fuel higher cortisol releases and severely impact the natural CAR. Delaying screen use while you get daylight and a protein breakfast preserves the physiological morning reset.

Daytime reset

Blood sugar stability - what and when to eat

Both skipping meals and high-sugar foods stimulate cortisol swings (as it is extremely stressful for the body). Aim for balanced meals every 4–5 hours with protein, fibre and healthy fats to steady glucose and stabilise cortisol levels. For snacks, think guacamole or hummus with crudités or an apple and nut butter.

Move, but not too late.

Gentle to moderate movement during the day (brisk walking, resistance work, or yoga) helps insulin sensitivity and supports circadian alignment. It also helps with emotional balance. It is best, however, to avoid high-intensity training in the late evening. It will keep your body temperature and cortisol too high, making it more difficult to fall asleep.

Caffeine cut-off - why 2 pm matters

Caffeine half-life is roughly 4–6 hours, and in many people it can still be active well into the evening after an afternoon coffee. That matters because caffeine can increase alertness and make you hyperaware or even anxious, especially in people who are already stressed or sensitive to stimulants. A 2.00 PM cut-off is a practical rule for people who want to protect their sleep and support a healthier cortisol rhythm. If you drink caffeine later in the day, it may not keep you 'wired' in an obvious way, but it can still make it harder for cortisol to come down at night and for your brain to fully shift into rest mode. That’s why a 3.00 PM coffee can still make you wired at 10.00 PM. If you are sensitive to stimulants, it is preferable that you avoid caffeine after midday.

Evening reset 

Magnesium glycinate before bed

Magnesium is a vital enzymatic cofactor that supports parasympathetic activity, nervous system regulation, and sleep. The glycinate form pairs magnesium with the amino acid glycine to deliver superior bioavailability and gastrointestinal tolerance. Because it is gentle and calming, it is commonly taken before bed.


Ashwagandha: timing and evidence

Ashwagandha extracts (notably KSM-66®) have the strongest evidence for reducing perceived stress and lowering cortisol in adults; most clinical trials used evening dosing and reported benefit over several weeks. The effect is gradual across 4–8 weeks and is not immediate, and relies on daily Ashwagandha KSM-66® or our formulation Stay Calm for added support.


Wind-down behaviours that actually work

From about 9.00 PM, dim the lights, avoid high-intensity content (fast-paced dramas, horror movies, heated social media); this also includes checking work emails, and keep a consistent bedtime. These cues help the brain recognise that it’s time to switch to repair mode. Also consider a brief journalling ritual and calming breathwork to help further. But do not stress about perfection; create automatisms that work for you.

Putting it together: a simple 4-week protocol

  • Week 1: Anchor mornings - daylight within 30 minutes, protein breakfast, no screens for 30 minutes.
  • Week 2: Add daytime structure - balanced meals every 4–5 hours, moderate
    movement, limit caffeine after midday.
  • Week 3: Introduce evening supports - magnesium glycinate 30–60 minutes before
    bed, dim lights from 9.00 PM, consistent bedtime, even on weekends.
  • Week 4: Add adaptogens, such as Ashwagandha KSM-66® in the evening for 6–8
    weeks if stress remains high. Track sleep quality, daytime energy, and mood weekly to gauge response.

When to see a GP

Lifestyle interventions can help re-establish cortisol rhythms for many people, but chronic dysregulation can lead to thyroid dysfunction, adrenal insufficiency, or (rarely) Cushing’s syndrome. If you’ve followed a consistent 4–6 week reset protocol with little or no improvement, or if your stress levels are constantly high, or if you have unexplained weight loss, muscle weakness, frequent infections, or markedly abnormal blood pressure, consult with your doctor. You may also want to identify your cortisol rhythms with diurnal testing, which includes taking a saliva sample at different times during the day.


This article was written by
Zakia Mance

Olivier Sanchez is a registered naturopath and naturopathic nutritionist, an internationally published author, and the founder of Nutrunity. He specialises in digestive, metabolic, and mental well-being, with a key focus on gut health and sleep, helping individuals create sustainable routines that enhance energy, focus, and overall health.

Visit his website: www.nutrunity.com.

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References
Bachour, G., Samir, A., Haddad, S. et al. (2025). Effects of ashwagandha supplements on cortisol, stress, and anxiety levels in adults: A systematic review and meta-analysis.
British Journal of Psychology Open. 11(Suppl. 1), S39. doi:10.1192/bjo.2025.10136
Bowles, NP., Thosar, SS., Butler, MP. et al. (2022). The circadian system modulates the cortisol awakening response in humans. Frontiers in Neuroscience. 16, 995452. doi:10.3389/fnins.2022.995452
Boyle, NB., Lawton, C., Dye, L. (2017). The effects of magnesium supplementation on subjective anxiety and stress – A systematic review. Nutrients. 9(5), 429. doi:10.3390/nu9050429
Chandrasekhar, K., Kapoor, J., Anishetty, S. (2012). A prospective, randomized double-blind, placebo-controlled study of safety and efficacy of a high-concentration full-spectrum extract of ashwagandha root in reducing stress and anxiety in adults. Indian Journal of Psychologic Medicine. 34(3), pp. 255-262. doi:10.4103/0253-7176.106022
Clow, A., Thorn, L., Evans, P. (2004). The awakening cortisol response: Methodological issues and significance. Stress. 7(1), pp. 29-37. doi:10.1080/10253890410001667205
Lopresti, AL., Smith, SJ., Malvi, H. et al. (2019). An investigation into the stress-relieving and pharmacological actions of an ashwagandha (Withania somnifera) extract: A randomized, double-blind, placebo-controlled study. Medicine (Baltimore). 98(37), e17186. doi:10.1097/MD.0000000000017186
Stalder, T., Kirschbaum, C., Kudielka, BM. et al. (2016). Assessment of the cortisol awakening response: Expert consensus guidelines. Psychoneuroendocrinology. 63, pp. 414-432. doi:10.1016/j.psyneuen.2015.10.010
Stalder, T., Oster, H., Abelson, JL. et al. (2025). The Cortisol Awakening Response.  Endocrine Reviews. 46(1), pp. 43–59. doi:10.1210/endrev/bnae024
Schutten, JC., Joris, PJ., Minović, I. et al. (2021). Long-term magnesium supplementation improves glucocorticoid metabolism: A post-hoc analysis of an intervention trial. Clinical Endocrinology (Oxf). 94(2), pp. 150-157. doi:10.1111/cen.14350

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