Supplements for Hormone Balance: What the Evidence Actually Says

What does "hormone balance" actually mean?

"Hormone balance" is one of the most searched health terms in the UK, but it is not a medical diagnosis. No GP will tell you that your hormones are "unbalanced" as a standalone finding. What they might tell you is that your thyroid function is abnormal, that your testosterone is low, that your cortisol is elevated, or that you have a condition like polycystic ovary syndrome (PCOS) — each of which involves specific hormones, specific tests, and specific treatments.

The reason this matters is that "hormone balance" has become a catch-all term used to sell supplements that claim to restore some vague equilibrium. The reality is more precise and, frankly, more useful. Certain nutrients have defined roles in hormonal regulation, thyroid function, fertility, and the body's stress response. Some of these roles are backed by EU-authorised health claims. Others are supported by clinical trial evidence. And many popular "hormone balance" ingredients have neither.

This article covers the nutrients with genuine regulatory or evidence-based links to hormonal health — what they can do, what they cannot do, and where the honest limits of supplementation lie.

Which nutrient has an authorised claim for hormonal activity?

Only one: vitamin B6.

Under EU Regulation 432/2012, retained in UK law, vitamin B6 "contributes to the regulation of hormonal activity." No other vitamin, mineral, or botanical extract in the UK supplement market carries a health claim specifically related to hormonal regulation.

This claim is based on B6's role as a coenzyme in the metabolism of amino acids and its involvement in the synthesis and turnover of steroid hormones and neurotransmitters. Specifically, B6 is a cofactor for enzymes involved in the production of serotonin, dopamine, noradrenaline, and GABA — neurotransmitters that interact closely with the endocrine system. It also plays a role in the metabolism of oestrogen and progesterone.

Wyatt et al. (1999) conducted a systematic review published in the BMJ examining nine randomised controlled trials of vitamin B6 supplementation and premenstrual symptoms. The review found an overall odds ratio of 2.32 for symptom improvement, meaning women taking B6 were significantly more likely to report improvement in hormone-related symptoms than those taking placebo.

This is not a dramatic or sensational finding. It is a well-established nutritional fact: B6 contributes to normal hormonal regulation, and inadequate intake can compromise that function.

PARTICULAR uses pyridoxine hydrochloride — the established, well-absorbed form of B6 — at doses that support the authorised claim.

Does zinc contribute to hormonal health?

Yes, through two specific authorised claims.

Zinc "contributes to the maintenance of normal testosterone levels in the blood" and "contributes to normal fertility and reproduction." Both are authorised under EU Regulation 432/2012.

The testosterone claim is particularly relevant. Zinc is essential for the normal function of the Leydig cells in the testes, which produce testosterone. Prasad et al. (1996) demonstrated this in a landmark study published in Nutrition, showing that dietary zinc restriction in young men was associated with a significant decrease in serum testosterone concentrations over 20 weeks, and that zinc supplementation in marginally zinc-deficient elderly men was associated with an increase in serum testosterone.

This does not mean zinc raises testosterone above normal levels — that language is not authorised and overstates the evidence. What the data shows is that adequate zinc status is necessary for the maintenance of normal testosterone levels, and that deficiency compromises this function.

Zinc also has a role in the process of cell division and contributes to the protection of cells from oxidative stress — both relevant to reproductive health.

PARTICULAR uses zinc bisglycinate, a chelated form with well-documented bioavailability and gastrointestinal tolerability. For a detailed comparison of zinc forms, see Zinc Supplements: Forms, Dosing and What to Look For.

How do selenium and iodine support thyroid function?

The thyroid gland produces hormones — primarily T3 and T4 — that regulate metabolic rate, energy production, and body temperature. Thyroid dysfunction is one of the most common hormonal disorders in the UK, affecting an estimated 1–2% of the population.

Two nutrients carry the authorised claim "contributes to normal thyroid function":

Selenium — a trace mineral that is a component of the deiodinase enzymes responsible for converting the inactive thyroid hormone T4 into the active form T3. Without adequate selenium, this conversion is impaired. Selenium also "contributes to normal fertility and reproduction" and "contributes to the protection of cells from oxidative stress" — both relevant to broader hormonal health.

Rayman (2012) published a comprehensive review in The Lancet examining the role of selenium in human health, including its relationship with thyroid function. The review confirmed selenium's essential role in thyroid hormone metabolism and highlighted the consequences of inadequate intake for thyroid health.

Iodine — a fundamental building block of thyroid hormones. The thyroid gland actively concentrates iodine from the bloodstream and uses it to synthesise T3 and T4. Without sufficient iodine, the thyroid cannot produce adequate hormones, regardless of how well other aspects of thyroid function are working.

Iodine also "contributes to normal energy-yielding metabolism" and "contributes to normal cognitive function" — both downstream effects of adequate thyroid hormone production.

Vanderpump et al. (2011) found that iodine deficiency was re-emerging as a public health concern in the UK, particularly among young women of childbearing age, with over two-thirds of schoolgirls in their study found to be iodine-deficient. For more on iodine's regulatory landscape in the UK, see Why Is Iodine Restricted in the UK?.

PARTICULAR uses iodine derived from Fucus vesiculosus L. extract (bladderwrack). An important safety note: if you take thyroid medication such as levothyroxine, iodine is excluded from your formula. Supplemental iodine can interfere with thyroid medication dosing, and the PARTICULAR questionnaire captures this to ensure your formula is safe.

What role does vitamin D play in hormonal health?

Vitamin D3 does not have an EU-authorised health claim specifically for hormonal activity. Its authorised claims relate to normal immune function, maintenance of normal bones, maintenance of normal muscle function, and a role in the process of cell division.

However, the vitamin D receptor (VDR) is expressed in tissues throughout the endocrine system, including the ovaries, testes, pituitary gland, and pancreas. This widespread expression provides a biological basis for vitamin D's involvement in hormonal processes.

Pilz et al. (2011) published a randomised controlled trial in Hormone and Metabolic Research examining the effect of vitamin D supplementation on testosterone levels in men. The study found that men receiving vitamin D supplementation showed significant increases in total testosterone, bioactive testosterone, and free testosterone levels compared to placebo — providing direct interventional evidence for a link between vitamin D status and hormonal outcomes.

The practical point is straightforward: vitamin D insufficiency is widespread in the UK. Public Health England recommends that all adults consider supplementing vitamin D during autumn and winter at minimum. Given the emerging evidence for its role in endocrine function, ensuring adequate vitamin D status is a sensible baseline measure.

PARTICULAR uses cholecalciferol from a vegan lichen source — the D3 form, which is more effective at raising blood levels than D2. For more, see Vitamin D Supplements: D3 vs D2.

Can magnesium help with stress hormones?

Magnesium "contributes to normal psychological function" — an authorised EU health claim. It also contributes to the reduction of tiredness and fatigue and to the normal functioning of the nervous system.

The relevance to hormonal health lies in the hypothalamic-pituitary-adrenal (HPA) axis — the system that governs the body's cortisol response to stress. Magnesium modulates this axis, and low magnesium status has been associated with increased HPA axis activity and elevated cortisol output.

Boyle et al. (2017) conducted a systematic review published in Nutrients examining the effects of magnesium supplementation on subjective anxiety and stress. The review found suggestive evidence that magnesium may have a beneficial effect, particularly in individuals who are vulnerable to stress or have low magnesium intake.

The National Diet and Nutrition Survey consistently shows that a significant proportion of UK adults do not meet recommended magnesium intake from diet alone. If stress or its downstream hormonal effects are a concern, ensuring adequate magnesium status is a rational starting point.

PARTICULAR uses magnesium citrate, a form with well-documented bioavailability. For more, see Magnesium for Sleep and Supplements for Stress and Anxiety.

Does ashwagandha affect hormonal health?

Ashwagandha KSM-66® does not have an EU-authorised health claim for hormonal activity, stress, or any other function. What follows is clinical trial evidence, not a regulatory approval.

KSM-66® is a standardised root extract of Withania somnifera and the most extensively studied form of ashwagandha in clinical trials.

Chandrasekhar et al. (2012) conducted a prospective, randomised, double-blind, placebo-controlled study of 64 adults with a history of chronic stress. Participants received either 300 mg KSM-66® twice daily or placebo for 60 days. The ashwagandha group showed significant reductions in scores on all stress-assessment scales compared to placebo, alongside a substantial reduction in serum cortisol levels — the primary stress hormone produced by the adrenal glands.

Lopresti et al. (2019) investigated the effects of ashwagandha on hormonal parameters in a randomised, double-blind, placebo-controlled, crossover study of ageing, overweight men. After 16 weeks of supplementation, clinical trial evidence suggests that the ashwagandha group experienced an 18% greater increase in DHEA-S and a 14.7% greater increase in testosterone compared to placebo.

These are well-designed trials with meaningful results, but the evidence base is still developing. Sample sizes are relatively small, and the mechanisms — thought to involve modulation of the HPA axis and cortisol regulation — are not fully established. Ashwagandha is not a treatment for hormonal conditions.

An important safety note: if you take immunosuppressant medication, ashwagandha is excluded from your PARTICULAR formula due to its immunomodulatory properties.

What about DIM, maca, vitex, and evening primrose oil?

These are among the most commonly marketed "hormone balance" supplements, so they deserve a direct statement: PARTICULAR does not contain any of them.

DIM (diindolylmethane) — derived from cruciferous vegetables, marketed for oestrogen metabolism. Limited clinical evidence in humans.
Maca — marketed for libido and hormonal health. Some preliminary evidence, but not sufficient for inclusion.
Vitex (chasteberry) — traditional use for premenstrual symptoms. Some positive trial data, but inconsistent quality and significant regulatory uncertainty.
Evening primrose oil — commonly suggested for hormonal symptoms. Clinical evidence is weak and inconsistent.

We do not include ingredients where the evidence does not meet our threshold for efficacy and safety, regardless of their popularity.

Supplements are not a treatment for hormonal conditions

This needs to be stated clearly. If you have been diagnosed with — or suspect — a hormonal condition such as PCOS, hypothyroidism, hyperthyroidism, adrenal insufficiency, or premature menopause, the correct course of action is to work with your GP or endocrinologist.

Nutritional supplementation can support the normal function of systems involved in hormonal regulation. It cannot treat, cure, or manage hormonal diseases. These conditions require medical investigation, monitoring, and — in many cases — pharmaceutical intervention.

For specific guidance on menstrual health, see Supplements for PMS and Periods. For perimenopause and menopause, see Supplements for Menopause.

Nutrients relevant to hormonal health

Nutrient	EU-Authorised Claim	Form in PARTICULAR	Relevance to Hormonal Health
Vitamin B6	Contributes to the regulation of hormonal activity	Pyridoxine Hydrochloride	The only nutrient with a hormone-related authorised claim
Zinc	Contributes to the maintenance of normal testosterone levels in the blood; contributes to normal fertility and reproduction	Zinc Bisglycinate	Essential for normal testosterone levels and reproductive function
Selenium	Contributes to normal thyroid function; contributes to normal fertility and reproduction	Sodium Selenite	Required for T4 to T3 thyroid hormone conversion
Iodine	Contributes to normal thyroid function	Fucus vesiculosus L. Extract	Building block of thyroid hormones T3 and T4
Vitamin D3	Has a role in the process of cell division	Cholecalciferol (vegan, from lichen)	VDR expressed across endocrine tissues; widespread UK deficiency
Magnesium	Contributes to normal psychological function	Magnesium Citrate	Modulates HPA axis and cortisol response
Ashwagandha KSM-66®	No authorised claim	KSM-66® Root Extract (≥5% withanolides)	Clinical trial evidence for cortisol modulation

How does PARTICULAR personalise for hormonal health?

PARTICULAR is not a "hormone balance supplement." It is a personalised supplement service that accounts for the nutritional factors involved in hormonal regulation as part of a broader assessment of your individual requirements.

The PARTICULAR questionnaire captures information about your stress levels, dietary patterns, health goals, and any medications or conditions that affect which ingredients are safe for you. This information is used to build a formula tailored to your specific profile.

In practice, this means:

Vitamin B6 is included at levels supporting the authorised claim for hormonal activity
Zinc, selenium, and iodine are dosed based on your dietary intake and health profile
Ashwagandha KSM-66® is included when your responses indicate elevated stress — and excluded if you take immunosuppressants
Iodine is excluded if you take thyroid medication
Magnesium and vitamin D3 are included as foundation ingredients in every formula

Your formula arrives as loose microgranules — one daily scoop, with each granule individually coated for targeted release and independent absorption.

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Key takeaways

"Hormone balance" is not a medical diagnosis. It is a broad term that covers many different hormonal systems, each with specific nutritional requirements.
Vitamin B6 is the only nutrient with the EU-authorised claim "contributes to the regulation of hormonal activity." It is the cornerstone of any evidence-based approach to hormonal support through supplementation.
Zinc contributes to the maintenance of normal testosterone levels in the blood and to normal fertility and reproduction. Adequate zinc status is necessary for these functions — deficiency compromises them.
Selenium and iodine both contribute to normal thyroid function. The thyroid gland produces hormones that regulate metabolism, energy, and body temperature. If you take thyroid medication, iodine is excluded from your formula.
Magnesium contributes to normal psychological function and modulates the HPA axis — the system governing cortisol, the primary stress hormone.
Clinical trial evidence suggests ashwagandha KSM-66® may reduce serum cortisol levels, but it does not have an EU-authorised health claim. If you take immunosuppressants, it is excluded from your formula.
DIM, maca, vitex, and evening primrose oil are not included in PARTICULAR. The evidence for these popular "hormone balance" ingredients does not meet our threshold.
If you have a hormonal condition such as PCOS, thyroid disease, or adrenal insufficiency, consult your GP. Supplements support normal function — they are not a substitute for medical treatment. Take the questionnaire to find out which nutrients are relevant for your individual profile.

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