Cozy tea time with chocolate and botanicals

Does Cortisol Cause Weight Gain? What the Evidence Says

You're not imagining it.

You eat well, you move, you sleep when you can, and the scales still creep up. Someone online told you the culprit is cortisol, your "stress hormone", and that eating less will only make it worse. It's a tidy story. It's also only partly true.

This is the corrected version of an article we published earlier. The first version said that most women make too much cortisol, that cutting calories makes you store fat, and that botanicals can regulate your stress system. When we checked the sources, several claims didn't hold up and a few citations were wrong, so we've rewritten it.

Here's the short version. Cortisol is a real part of how your body handles energy, and when it's far above normal for a long time, as in Cushing's syndrome or with long-term steroid tablets, it causes weight gain around the middle. For everyday stress, the research is small, mixed and mostly observational. Eating less is still how NICE says weight loss works. And if you have PMOS (PCOS), are in perimenopause, or have a stubborn pattern of symptoms, there are better-evidenced explanations worth ruling out first. Your body is trying to tell you something, but it's rarely just "your cortisol is high".

A woman in a cream knit jumper sits at a wooden kitchen table in warm evening light, holding a ceramic mug and looking out of the window, with an open notebook, a glass of water and a sprig of eucalyptus beside her

In this guide:

What Is Cortisol and What Does It Do?

In short: Cortisol is a steroid hormone made by your adrenal glands. It follows a daily rhythm and helps your body manage energy, blood sugar and stress.

Cortisol is made by your adrenal glands, two small glands that sit on top of your kidneys. It's usually highest soon after you wake and falls to its lowest late at night. It helps your body release stored glucose, keeps blood pressure steady and is part of your response to stress. The NHS describes cortisol and adrenaline as hormones your body releases when you feel anxious or under pressure [1].

That's normal physiology, not a fault. The trouble starts with the popular story that modern women are all running on permanently high cortisol. We couldn't find any evidence for that. The best review of the research, covering 107 studies and 8,521 people, found that cortisol patterns depend on the type of stressor and the timing: levels tend to rise near the start of a stressor and then fall again with time, and a threatening, uncontrollable stressor is more likely to flatten the daily rhythm than to raise it all day [2].

Plenty of women are under sustained pressure, and that matters. But "I'm stressed" and "my cortisol is high" are different statements, and only one of them can be tested.

Does Cortisol Cause Weight Gain?

In short: Yes, when it's far above normal for a long time, as in Cushing's syndrome. For everyday stress the evidence is small, mixed and mostly observational.

The clearest evidence comes from conditions where cortisol is extremely high. In Cushing's syndrome, usually caused by long-term steroid medicine, fat builds up on the neck, upper back, chest and tummy while the arms and legs get thinner [3]. Steroid medicines also raise blood sugar, because they push the liver to release glucose and make muscle less responsive to insulin. One review cites studies in which roughly a third to a half of people on steroid treatment developed raised blood sugar or diabetes [4].

Everyday stress is a different question. A pooled analysis of 13 European studies covering 124,808 people found that people with high job strain had a 15% higher risk of type 2 diabetes over about 10 years, and the link shrank to 11% and became borderline after adjusting for lifestyle. Cortisol wasn't measured [5]. That's a modest association, not proof.

So cortisol helps regulate blood sugar and fat storage, and when it's extremely high it can cause weight gain. Within the normal range, as it is for most people with stressful lives, we can't say it's why the scales are moving.

Does Stress Make You Eat More?

In short: For many people, yes. In one small lab study, women with the biggest cortisol response to stress ate more sweet food. It isn't a character flaw.

This is the part of the cortisol story with the most human evidence, and it's worth knowing. In one laboratory study of 59 healthy premenopausal women, each woman had a stress day and a no-stress day. Women whose cortisol rose the most in response to stress ate more on the stress day, and ate more sweet food across both days [6].

You'll often read that cortisol triggers a brain chemical called neuropeptide Y that drives hunger and fat storage. That mechanism comes mainly from rat research, including a well-known 2003 model of "comfort food" eating in stressed animals [7]. We found no human study showing that cortisol triggers neuropeptide Y release.

Stress eating is common, human and not a willpower problem. If it's a pattern for you, dealing with the source of the stress and eating regular, satisfying meals usually helps more than tougher rules.

Does Cortisol Cause Belly Fat?

In short: In Cushing's syndrome, yes. In the general population, higher long-term cortisol is linked with a larger waist, but the link is small.

Visceral fat, the fat around your organs, does contain glucocorticoid receptors, the docking points for cortisol. A 1990 study of human fat tissue found these receptors in fat, with more binding in intra-abdominal fat than in fat under the skin [8]. That's a lab finding, not proof that daily stress builds belly fat.

Studies in living women are suggestive but not conclusive. In one of 59 healthy premenopausal women, those with a higher waist-to-hip ratio produced more cortisol in response to a stress test [9]. A large meta-analysis of hair cortisol studies, covering 146 cohorts and 34,342 people, found a small link between long-term cortisol exposure and waist circumference (a correlation of 0.18) and an even smaller one with BMI (0.10) [10]. These studies are cross-sectional, so they can't tell us which comes first. Carrying more weight might change cortisol, rather than the other way round.

A small link isn't nothing, but it's a long way from "cortisol is why you have a belly".

Does Poor Sleep Drive Weight Gain?

In short: Short sleep raised hunger and appetite in small trials, and one trial of extra sleep cut calorie intake. Its effect on cortisol is mixed.

Sleep is the lifestyle factor with the best human evidence here, although the studies are small. In a trial of 12 young men, two nights of 4 hours in bed instead of 10 lowered the fullness hormone leptin by about 18%, raised the hunger hormone ghrelin by about 28% and raised hunger by about 24% [11].

There's also real-world evidence. In a randomised trial of 80 adults with overweight, those who extended their sleep by about 1.2 hours a night ate roughly 270 fewer calories a day than the control group over two weeks [12].

Cortisol is where the story gets less tidy. One classic study found evening cortisol was 37% higher after a partial night of lost sleep [13], but a later small study of 11 men found no rise in baseline daytime cortisol after short sleep [14]. So "poor sleep raises cortisol" is plausible, not settled.

The NHS says most healthy adults need around 7 to 9 hours a night [15]. If your sleep falls apart before your period, our guide to why you can't sleep before your period covers what's going on.

Does Eating Less Make Cortisol Worse?

In short: Strict dieting can raise measured cortisol, but it doesn't stop weight loss. NICE still says energy in has to be below energy out to lose weight.

The first version said eating less makes your body "prioritise fat storage". That was too strong. Here's what the studies behind it show.

In a three-week study of 121 women, those put on 1,200 kcal a day had higher cortisol, measured in saliva, than women who weren't restricting. Women who simply monitored their calories reported more stress. The restricting group also lost weight, about 1.9 lb on average, and the study wasn't designed to test whether dieting causes weight gain [16].

A second study is often quoted as proof that stress "stores" a meal. It was a trial of 58 women, mostly breast cancer survivors with an average age of 53. Women who'd had one or more stressful events in the previous 24 hours burned about 104 fewer calories over the next seven hours after a high-fat meal. The authors' 11 lb a year figure is a projection, not something they observed [17].

Neither study shows that eating less prevents weight loss. NICE's obesity guideline still advises keeping total energy intake below energy expenditure, while avoiding restrictive diets that are nutritionally unbalanced [18]. The 2023 international guideline and the NICE draft for PMOS both say there's no evidence that any one diet composition is better than another [19, 20].

The sensible reading: crash dieting is stressful and rarely sustainable, so regular, balanced meals are a better starting point, and being stressed doesn't mean you can't lose weight. If you have a history of an eating disorder, talk to your GP before restricting anything [20].

Is "Adrenal Fatigue" Real?

In short: No. The Endocrine Society says there's no scientific proof that adrenal fatigue is a medical condition, and no test that can detect it.

You'll see "adrenal fatigue" and "HPA axis dysfunction" used online as if they were established diagnoses, usually just before a list of supplements. They aren't. The Endocrine Society says no scientific proof exists to support adrenal fatigue as a true medical condition, that no test can detect it, and that supplements sold for it may be unsafe [21]. A systematic review of 58 studies reached the same conclusion [22].

Real adrenal conditions exist, such as Cushing's syndrome and Addison's disease, and they need proper testing. If you're exhausted, a GP can check for the more common causes first, including anaemia, thyroid problems, sleep apnoea and depression.

What About PMOS (PCOS), Your Cycle and Perimenopause?

In short: About 1 in 4 to 1 in 3 women with PMOS have raised adrenal androgens (DHEAS). The cause isn't simply high cortisol, and it isn't a separate type.

PMOS (PCOS)

A 2007 review found that between 20% and 30% of women with PMOS (PCOS) have adrenal androgen excess, usually picked up as a high DHEAS level. The cause isn't fully understood. It seems to involve an altered adrenal response to ACTH, the pituitary hormone that tells your adrenal glands to work, and changes in how cortisol is broken down, and it appears to run in families. It isn't simply "cortisol stimulating androgens" [23].

Neither the 2023 international guideline nor the NICE draft for PMOS recommends routine cortisol testing. DHEAS is mainly used to help with diagnosis when testosterone isn't raised, and to help rule out other causes of raised androgens [19, 20]. In one study that adjusted for age and BMI, salivary cortisol didn't differ between women with PMOS and controls, although the women with PMOS reported more perceived stress [24]. For more on the adrenal side, see our guide to adrenal PCOS.

Your menstrual cycle

A 1999 study found that the free cortisol response to a stress test was highest in women in the second half of their cycle, lower in the first half, and lower in women taking the pill [25]. A 2023 meta-analysis found a small, similar rise in the luteal phase and said more high-quality studies were needed [26]. The differences are small, and none of this shows that oestrogen "amplifies cortisol sensitivity", as our first version claimed.

Perimenopause

During perimenopause, oestrogen and progesterone levels swing and fall. Progesterone is converted in the body into allopregnanolone, which acts on calming GABA receptors in the brain [27], which is one reason sleep and mood can get harder. We found no study showing that cortisol rises more easily when progesterone drops.

What the research does show about weight is more specific than "it's your oestrogen". In the SWAN study, fat mass gain roughly doubled and lean mass fell around the start of the menopause transition, while total weight didn't accelerate [28]. Your body composition can shift even if the scales barely move, which is a good reason to include strength training. The NHS lists sleep problems, anxiety and low mood among the symptoms [29]; our perimenopause guide has the full picture.

When Should You See Your GP?

In short: See your GP if you have rapid weight gain around your middle with easy bruising, stretch marks or muscle weakness, or if you take steroid tablets.

Cushing's syndrome is rare, but it's the one cortisol condition worth knowing about, because it's treatable. The NHS lists these symptoms [3]:

  • Fat building up on the neck, upper back, chest and tummy, with thinner arms and legs
  • A rounded, reddened face
  • Easy bruising and stretch marks on the abdomen, hips, breasts and underarms
  • Muscle weakness, especially in the upper arms and thighs
  • Mood changes, such as irritability, anxiety or low mood
  • Irregular periods or periods that stop, and excess hair growth

The NHS says to see a GP if you have symptoms of Cushing's syndrome, particularly if you take steroid medicine. If it's suspected, a GP may check cortisol in a blood, urine or saliva sample [3].

Please don't self-diagnose from a list of common symptoms. Afternoon sugar cravings, waking at 3am, shorter cycles, intense PMS and a mid-month energy crash are not "signs of cortisol". They have many causes, including an underactive thyroid (ask for a thyroid blood test that checks TSH and thyroxine [30]), sleep apnoea, which the NICE draft says is common in people with PMOS regardless of weight [20, 31], perimenopause, PMDD, low iron, and depression. Our thyroid guide explains the test.

If you feel low or anxious most days, you can refer yourself to NHS Talking Therapies without a GP referral in England [32].

What Actually Helps?

In short: Sleep, regular meals, movement you can keep doing and dealing with the sources of stress. Evidence for lowering cortisol itself is limited.

This is what I wish someone had told me: the things that help with stress, sleep and weight are mostly the same, and they don't need a cortisol test.

Sleep. Aim for 7 to 9 hours. The NHS suggests relaxing for at least an hour before bed and keeping your bedroom dark and quiet [15, 33].

Movement. UK guidelines are at least 150 minutes of moderate activity a week, or 75 minutes of vigorous activity, plus strengthening activities on at least 2 days a week [34]. Hard exercise raises cortisol temporarily, which is normal. The 2023 guideline and the NICE draft both found a lack of evidence that any type or intensity of exercise is better than another for PMOS, so choose what you can keep doing and recover from [19, 20].

Food. Regular meals that include protein, fibre-rich carbohydrate and healthy fats suit most people, and no single diet composition has been shown to be best [19, 20]. Our guide to blood sugar balance covers the practical side.

Stress. The NHS suggests breathing exercises, talking to someone, planning ahead, staying active and NHS Talking Therapies [1, 32]. Do they lower cortisol itself? The evidence is limited and mixed. A meta-analysis of 5 trials (190 people) found mindfulness-based programmes were linked to lower salivary cortisol, but not compared with an active control [35]. They're still worth trying, because feeling less stressed is worth having on its own. Our guide to nervous system regulation goes deeper.

Where Does the MyOva Magnesium Nightcap Fit In?

In short: The Nightcap is a bedtime drink with 250 mg magnesium and 5 mg vitamin B6. It's a food supplement, not a treatment for stress or weight gain.

The first version of this article called the Nightcap a "hormonal reset" and linked its ingredients to cortisol. We can't support that. Here's what's actually in each serving, and what the research does and doesn't say.

MyOva Magnesium Nightcap Hot Chocolate
Daily Food Supplement
Magnesium Nightcap Hot Chocolate

A bedtime hot chocolate with magnesium bisglycinate (250 mg elemental magnesium) and vitamin B6. 30 servings. Food supplement, not a medicine.

Ingredient (per 12 g serving) Amount What to know
Magnesium bisglycinate 250 mg elemental magnesium Contributes to normal nervous system function and the reduction of tiredness and fatigue [36]. Sleep trials are small and the evidence is low certainty [37, 38].
L-glycine 3,000 mg The amount used in small volunteer studies, which were short and had bias concerns [39, 40].
Chamomile extract (20:1) Equivalent to 300 mg Human sleep evidence is mixed [41].
Lavender extract (4:1) Equivalent to 100 mg Most human sleep research is on inhaled lavender [42].
Montmorency cherry extract (10:1) Equivalent to 2,000 mg Small trials used juice [43].
Reishi extract (15:1) Equivalent to 400 mg We found no human trials we could cite for stress or sleep.
Vitamin B6 5 mg Contributes to the regulation of hormonal activity, normal psychological function, normal nervous system function and the reduction of tiredness and fatigue [36].
Bacillus coagulans, chicory inulin, MCT oil 2 billion CFU, 2,000 mg, 600 mg No health claim is made for these.

Mix one scoop (12 g) into 250 ml of hot water or milk, 30 to 60 minutes before bed. No ingredient in it has an authorised claim for lowering cortisol, regulating your stress system or helping you lose weight, and it won't replace the sleep, movement and meal habits above.

Safety first. It isn't suitable for children, or for anyone pregnant or breastfeeding. Avoid it if you're allergic to plants in the daisy family, such as ragweed, because of the chamomile [44]. If you take prescribed medicines, ask your pharmacist about timing: magnesium-containing products can reduce how well some antibiotics work [45]. Count any other magnesium supplement towards the 400 mg guide, as the Nightcap provides 250 mg [46]. The NHS advises not taking more than 10 mg of vitamin B6 a day from supplements unless a doctor says so, and the Nightcap provides 5 mg, so check any other B6 you take [47]. Speak to your GP or pharmacist if you have kidney problems or take other medicines.

Not sure which MyOva product, if any, suits you? Take the free quiz and get 20% off.

Infographic titled Cortisol and Weight: What the Research Shows, with three panels: clear evidence, small or mixed evidence, and not supported

What Does the Evidence Support? A Quick Summary

In short: Cortisol matters when it's far above normal. For everyday stress, sleep and dieting the evidence is small or mixed, and some popular claims fail.

Claim What the research shows Strength
Extremely high cortisol causes weight gain around the middle Established in Cushing's syndrome and with long-term steroid treatment Strong
Everyday stress raises cortisol enough to cause weight gain Small, mostly observational links; direction unclear Weak
Stress increases appetite for sweet food One lab study of 59 women; the neuropeptide Y mechanism comes from rat research Weak
Cortisol drives belly fat Small cross-sectional links with waist size Weak
Short sleep raises hunger Small trials in young men; one trial of extra sleep cut about 270 kcal a day Moderate
Eating less raises cortisol, so you cannot lose weight Cortisol was higher in one 3-week study, but weight still fell Not supported
"Adrenal fatigue" explains your symptoms No scientific proof and no test Not supported
Supplements can lower or regulate your cortisol No authorised claim; ingredient evidence is limited or low certainty Not supported

Frequently Asked Questions

Can cortisol cause weight gain even if I eat well?

When it's far above normal for a long time, yes, as in Cushing's syndrome or with long-term steroid tablets. For everyday stress the evidence is weaker, and a GP can check for other causes such as thyroid problems [3, 10].

Does cortisol cause belly fat specifically?

In Cushing's syndrome, fat builds up around the middle. In the general population the link between long-term cortisol and waist size is small and can't show cause and effect [3, 10].

Is cortisol the same as adrenaline?

No. Adrenaline acts within seconds, while cortisol is released more slowly and its effects last longer. Both are stress hormones, and some of their effects, such as raising blood sugar, overlap [1].

How long does it take to lower cortisol?

There's no reliable timeline. Cortisol patterns vary with the type and timing of stress, and you can't track yours at home. Focus on what you can notice and measure: your sleep, your energy, your symptoms and how you feel [2].

Should I take ashwagandha for cortisol?

We don't recommend it. The Food Standards Agency says no safe level has been established for ashwagandha in food supplements in the UK and is looking into it. If you're thinking about it, ask your GP or pharmacist first [48].

The Bottom Line

Cortisol is real, and it matters. When it's far above normal, it can change your weight, your blood sugar and your periods. But for most women with a stressful life and a stubborn scale, the research doesn't show that cortisol is the reason, and eating less isn't the problem it was made out to be.

Look at sleep, regular meals, movement you can keep doing and the sources of stress. Ask your GP to rule out thyroid problems, sleep apnoea and, if the symptoms fit, Cushing's. Hormonal literacy isn't complicated, it's just rarely taught. Your diagnosis is a starting point, not a verdict, and so is a stubborn number on the scales.

Related Reading

This article is for educational purposes only and does not constitute medical advice. Guidance details are accurate to the sources cited at the time of writing and may change. The MyOva Magnesium Nightcap Hot Chocolate is a food supplement, not a medicine, and is not intended to diagnose, treat, cure or prevent any disease. Food supplements should not replace a varied diet. If you have concerns about your weight, periods, sleep or mood, speak to your GP before making changes.

References

  1. NHS. Stress. https://www.nhs.uk/mental-health/feelings-symptoms-behaviours/feelings-and-symptoms/stress/
  2. Miller GE, Chen E, Zhou ES. If it goes up, must it come down? Chronic stress and the hypothalamic-pituitary-adrenocortical axis in humans. Psychol Bull. 2007;133(1):25-45. doi:10.1037/0033-2909.133.1.25
  3. NHS. Cushing's syndrome. https://www.nhs.uk/conditions/cushings-syndrome/ and Cushing's syndrome: symptoms. https://www.nhs.uk/conditions/cushings-syndrome/symptoms/
  4. Tamez-Pérez HE, et al. Steroid hyperglycemia: prevalence, early detection and therapeutic recommendations: a narrative review. World J Diabetes. 2015;6(8):1073-1081. doi:10.4239/wjd.v6.i8.1073
  5. Nyberg ST, et al. Job strain as a risk factor for type 2 diabetes: a pooled analysis of 124,808 men and women. Diabetes Care. 2014 (volume and pages not confirmed here)
  6. Epel E, Lapidus R, McEwen B, Brownell K. Stress may add bite to appetite in women: a laboratory study of stress-induced cortisol and eating behavior. Psychoneuroendocrinology. 2001;26(1):37-49. doi:10.1016/s0306-4530(00)00035-4
  7. Dallman MF, Pecoraro N, Akana SF, et al. Chronic stress and obesity: a new view of "comfort food". Proc Natl Acad Sci USA. 2003;100(20):11696-11701. doi:10.1073/pnas.1934666100
  8. Rebuffé-Scrive M, Brönnegård M, Nilsson A, Eldh J, Gustafsson JA, Björntorp P. Steroid hormone receptors in human adipose tissues. J Clin Endocrinol Metab. 1990;71(5):1215-1219
  9. Epel ES, McEwen B, Seeman T, et al. Stress and body shape: stress-induced cortisol secretion is consistently greater among women with central fat. Psychosom Med. 2000;62(5):623-632. doi:10.1097/00006842-200009000-00005
  10. van der Valk E, et al. Cross-sectional relation of long-term glucocorticoids in hair with anthropometric measurements and their possible determinants: a systematic review and meta-analysis. Obes Rev. 2022;23(3):e13376. doi:10.1111/obr.13376
  11. Spiegel K, Tasali E, Penev P, Van Cauter E. Brief communication: sleep curtailment in healthy young men is associated with decreased leptin levels, elevated ghrelin levels, and increased hunger and appetite. Ann Intern Med. 2004;141(11):846-850
  12. Tasali E, Wroblewski K, Kahn E, Kilkus J, Schoeller DA. Effect of sleep extension on objectively assessed energy intake among adults with overweight in real-life settings: a randomized clinical trial. JAMA Intern Med. 2022 (volume and pages not confirmed here)
  13. Leproult R, Copinschi G, Buxton O, Van Cauter E. Sleep loss results in an elevation of cortisol levels the next evening. Sleep. 1997;20(10):865-870
  14. Guyon A, et al. Effects of insufficient sleep on pituitary-adrenocortical response to CRH stimulation in healthy men. Sleep. 2017;40(6):zsx064. doi:10.1093/sleep/zsx064
  15. NHS Every Mind Matters. Sleep. https://www.nhs.uk/every-mind-matters/mental-health-issues/sleep/
  16. Tomiyama AJ, Mann T, Vinas D, Hunger JM, Dejager J, Taylor SE. Low calorie dieting increases cortisol. Psychosom Med. 2010;72(4):357-364. doi:10.1097/PSY.0b013e3181d9523c
  17. Kiecolt-Glaser JK, Habash DL, Fagundes CP, et al. Daily stressors, past depression, and metabolic responses to high-fat meals: a novel path to obesity. Biol Psychiatry. 2015;77(7):653-660. doi:10.1016/j.biopsych.2014.05.018
  18. National Institute for Health and Care Excellence. Overweight and obesity management. NICE guideline NG246 (2025), recommendations 1.16.3 and 1.16.7. https://www.nice.org.uk/guidance/NG246/chapter/physical-activity-and-diet (wording as relayed)
  19. Teede HJ, Tay CT, Laven JJE, et al. Recommendations from the 2023 international evidence-based guideline for the assessment and management of polycystic ovary syndrome. Hum Reprod. 2023;38(9):1655-1679. doi:10.1093/humrep/dead156
  20. National Institute for Health and Care Excellence. Polycystic ovary syndrome: assessment and management. Draft guideline GID-NG10436, consultation 1 July to 11 August 2026 (final expected December 2026). https://www.nice.org.uk/guidance/gid-ng10436
  21. Endocrine Society. Adrenal fatigue (patient information). https://www.endocrine.org/patient-engagement/endocrine-library/adrenal-fatigue
  22. Cadegiani FA, Kater CE. Adrenal fatigue does not exist: a systematic review. BMC Endocr Disord. 2016;16:48. doi:10.1186/s12902-016-0128-4
  23. Yildiz BO, Azziz R. The adrenal and polycystic ovary syndrome. Rev Endocr Metab Disord. 2007;8(4):331-342. doi:10.1007/s11154-007-9054-0
  24. Marschalek M-L, et al. [Salivary cortisol in women with polycystic ovary syndrome; exact title and author list not confirmed here]. Front Endocrinol. 2023;14:1173422. doi:10.3389/fendo.2023.1173422
  25. Kirschbaum C, Kudielka BM, Gaab J, Schommer NC, Hellhammer DH. Impact of gender, menstrual cycle phase, and oral contraceptives on the activity of the hypothalamus-pituitary-adrenal axis. Psychosom Med. 1999;61(2):154-162. doi:10.1097/00006842-199903000-00006
  26. Klusmann H, et al. Menstrual cycle-related changes in HPA axis reactivity to acute psychosocial and physiological stressors: a systematic review and meta-analysis of longitudinal studies. Neurosci Biobehav Rev. 2023;150:105212. doi:10.1016/j.neubiorev.2023.105212
  27. Hamidovic A, Karapetyan K, Serdarevic F, Choi SH, Eisenlohr-Moul T, Pinna G. Higher circulating cortisol in the follicular vs. luteal phase of the menstrual cycle: a meta-analysis. Front Endocrinol. 2020;11:311. doi:10.3389/fendo.2020.00311
  28. Greendale GA, Sternfeld B, Huang M, et al. Changes in body composition and weight during the menopause transition. JCI Insight. 2019;4(5):e124865. doi:10.1172/jci.insight.124865
  29. NHS. Menopause: symptoms. https://www.nhs.uk/conditions/menopause/symptoms/
  30. NHS. Underactive thyroid (hypothyroidism): diagnosis. https://www.nhs.uk/conditions/underactive-thyroid-hypothyroidism/diagnosis
  31. NHS. Sleep apnoea. https://www.nhs.uk/conditions/sleep-apnoea/
  32. NHS. NHS Talking Therapies. Last reviewed 5 November 2025. https://www.nhs.uk/mental-health/talking-therapies-medicine-treatments/talking-therapies-and-counselling/nhs-talking-therapies/
  33. NHS. Insomnia. Reviewed 19 March 2024. https://www.nhs.uk/conditions/insomnia/
  34. NHS. Physical activity guidelines for adults aged 19 to 64. https://www.nhs.uk/live-well/exercise/exercise-guidelines/physical-activity-guidelines-for-adults-aged-19-to-64/
  35. Sanada K, et al. Effects of mindfulness-based interventions on salivary cortisol in healthy adults: a meta-analytical review. Front Physiol. 2016;7 (article number not confirmed here)
  36. Commission Regulation (EU) No 432/2012 establishing a list of permitted health claims (retained in Great Britain); see the GB Nutrition and Health Claims Register. https://www.gov.uk/government/publications/great-britain-nutrition-and-health-claims-nhc-register
  37. Mah J, Pitre T. Oral magnesium supplementation for insomnia in older adults: a systematic review and meta-analysis. BMC Complement Med Ther. 2021;21:125. doi:10.1186/s12906-021-03297-z
  38. Schuster J, Cycelskij I, Lopresti A, Hahn A. Magnesium bisglycinate supplementation in healthy adults reporting poor sleep: a randomized, placebo-controlled trial. Nat Sci Sleep. 2025;17:2027-2040. doi:10.2147/NSS.S524348
  39. Yamadera W, Inagawa K, Chiba S, Bannai M, Takahashi M, Nakayama K. Glycine ingestion improves subjective sleep quality in human volunteers, correlating with polysomnographic changes. Sleep Biol Rhythms. 2007;5:126-131. doi:10.1111/j.1479-8425.2007.00262.x
  40. Soh J, Raventhiran S, Lee JH, et al. The effect of glycine administration on the characteristics of physiological systems in human adults: a systematic review. GeroScience. 2024;46(1):219-239. doi:10.1007/s11357-023-00970-8
  41. Hieu TH, Dibas M, Dila KAS, et al. Therapeutic efficacy and safety of chamomile for state anxiety, generalized anxiety disorder, insomnia, and sleep quality: a systematic review and meta-analysis of randomized trials and quasi-randomized trials. Phytother Res. 2019;33(6):1604-1615.
  42. Fismer KL, Pilkington K. Lavender and sleep: a systematic review of the evidence. Eur J Integr Med. 2012;4(4):e436-e447.
  43. Howatson G, Bell PG, Tallent J, Middleton B, McHugh MP, Ellis J. Effect of tart cherry juice (Prunus cerasus) on melatonin levels and enhanced sleep quality. Eur J Nutr. 2012;51(8):909-916. doi:10.1007/s00394-011-0263-7
  44. European Medicines Agency, Committee on Herbal Medicinal Products. European Union herbal monograph on Matricaria recutita L., flos. 2015. https://www.ema.europa.eu/en/documents/herbal-monograph/final-european-union-herbal-monograph-matricaria-recutita-l-flos-first-version_en.pdf
  45. electronic Medicines Compendium. Doxycycline capsules: patient information leaflet. https://www.medicines.org.uk/emc/files/pil.13082.pdf
  46. NHS. Vitamins and minerals: others (including magnesium). https://www.nhs.uk/conditions/vitamins-and-minerals/others/
  47. NHS. Vitamins and minerals: B vitamins and folic acid. https://www.nhs.uk/conditions/vitamins-and-minerals/vitamin-b/
  48. Food Standards Agency. Ashwagandha: call for evidence (no safe level established for food supplements; risk assessment pending). https://www.food.gov.uk/news-alerts/consultations/ashwagandha
Leila Martyn

Leila Martyn

Leila is the founder of MyOva, a UK-based hormonal health brand for women with PMOS (PCOS), endometriosis, perimenopause, PMDD and fertility challenges. Drawing on lived experience and scientific research, she shares evidence-based guidance to help women feel informed about their hormones and cycles.

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References