Zinc and hair loss are closely linked through the mineral's essential role in supporting healthy hair follicle function and the hair growth cycle. Zinc is a trace mineral required for cell division, keratin production, and immune regulation — all processes critical to maintaining normal hair growth. When zinc levels fall below optimal, follicles can shift prematurely into the resting phase, triggering diffuse shedding known as telogen effluvium. This article explores how zinc deficiency contributes to hair thinning, who is most at risk in the UK, the best dietary sources, supplement safety considerations, and when to seek a GP assessment.

How Zinc Affects Hair Growth and Loss

Zinc supports keratin production and follicular cell division; deficiency can prematurely shift follicles into the telogen phase, causing diffuse shedding known as telogen effluvium.

Zinc is an essential trace mineral involved in cell division, protein synthesis, and immune function. Within the hair follicle, zinc supports normal follicular activity and helps regulate the hair growth cycle. Hair follicles are among the most rapidly dividing cells in the body, making them particularly sensitive to nutritional deficiencies.

Zinc contributes to the production of keratin — the primary structural protein of the hair shaft — and acts as a cofactor for enzymes involved in DNA replication and repair, processes that are critical for sustaining healthy follicular activity. It also plays a role in the normal function of sebaceous glands surrounding the follicle.

In states of zinc deficiency, the hair growth cycle can be disrupted. Follicles may shift prematurely from the anagen (active growth) phase into the telogen (resting) phase, leading to increased shedding — a pattern known as telogen effluvium. It is important to note that both zinc deficiency and chronic excessive zinc intake can contribute to hair shedding; in the case of excess, this occurs indirectly through zinc-induced copper deficiency (see the section on supplements below).

Hair loss is rarely attributable to a single nutritional cause, and zinc is just one of many factors influencing follicular health. Any concerns about hair shedding should be assessed clinically rather than attributed to zinc status alone.

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Signs of Zinc Deficiency Linked to Hair Thinning

Zinc deficiency typically causes diffuse, non-scarring scalp thinning alongside symptoms such as slow wound healing, brittle nails, and reduced taste or smell, all of which are reversible once the deficiency is corrected.

Zinc deficiency can manifest in a variety of ways, and hair thinning or loss is one of the more commonly reported symptoms. The hair loss associated with low zinc levels typically presents as diffuse thinning across the scalp rather than patchy or localised loss. This pattern reflects the systemic nature of nutritional deficiency, affecting follicles broadly. The hair loss is usually a non-scarring telogen effluvium and is generally reversible once the deficiency is corrected, though recovery may take several months as the hair growth cycle normalises.

Other signs that may accompany zinc deficiency include:

• Slow wound healing — zinc is integral to tissue repair and immune response

• Dry, flaky skin or dermatitis — particularly around the nose, mouth, and eyes

• Brittle or ridged nails

• Reduced sense of taste or smell (hypogeusia or hyposmia)

• Frequent infections — due to impaired immune function

• Fatigue and poor concentration

Many of these symptoms overlap with other conditions, including thyroid disorders, iron deficiency anaemia, and other nutritional deficiencies. Hair thinning in particular has a broad differential diagnosis. There is no established link between mild zinc insufficiency and severe or permanent hair loss.

If you notice a combination of the above symptoms alongside increased hair shedding, seek a clinical assessment rather than self-diagnosing or self-supplementing. It is also worth noting that unvalidated 'hair mineral analysis' tests sold commercially are not a reliable method of diagnosing zinc deficiency and are not recommended by UK clinical bodies.

Who Is Most at Risk of Low Zinc Levels in the UK

Vegetarians, vegans, older adults, breastfeeding women, and those with gastrointestinal conditions such as Crohn's disease or coeliac disease are at greatest risk of suboptimal zinc status in the UK.

Outright zinc deficiency is relatively uncommon in the general UK population, but certain groups are at meaningfully higher risk of suboptimal zinc status. Data from the National Diet and Nutrition Survey (NDNS) indicate that some adolescents, older adults, and those following restrictive diets have lower zinc intakes than recommended.

Groups at increased risk include:

• Vegetarians and vegans — plant-based diets tend to be lower in bioavailable zinc. Phytates found in wholegrains, legumes, and seeds bind to zinc and reduce its absorption in the gut.

• Older adults — zinc absorption may decrease with age, and dietary intake can be lower due to reduced appetite or restricted diets.

• Breastfeeding women — UK Dietary Reference Values (DRVs) indicate a modest increase in zinc requirements during lactation. There is no increase in the Reference Nutrient Intake (RNI) for zinc during pregnancy itself.

• People with gastrointestinal conditions — conditions such as Crohn's disease, ulcerative colitis, or coeliac disease impair nutrient absorption, including zinc.

• Those with alcohol dependency — alcohol increases urinary zinc excretion and may reduce dietary intake.

• Individuals following very low-calorie or restrictive diets — including those with eating disorders.

• Adolescents — NDNS data suggest some teenagers in the UK have zinc intakes below the RNI.

People taking certain medicines may also be at risk of reduced zinc status over time. Notably, some diuretics and proton pump inhibitors (PPIs) may affect zinc levels with prolonged use. Penicillamine (used in conditions such as rheumatoid arthritis and Wilson's disease) can reduce zinc absorption and is a recognised interaction. If you are taking any long-term medicines and are concerned about nutritional status, speak to your GP or pharmacist.

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If you fall into one or more of these categories and are experiencing hair thinning, a GP assessment is a sensible first step.

Dietary Sources of Zinc and Lifestyle Considerations

The richest dietary sources of bioavailable zinc are meat, poultry, and shellfish; the UK RNI is 9.5 mg/day for men and 7 mg/day for women, and supplements above 25 mg/day can cause adverse effects.

The most effective and safest way to maintain adequate zinc levels is through a balanced, varied diet. The UK Reference Nutrient Intake (RNI) for zinc is 9.5 mg per day for adult men and 7 mg per day for adult women, as set by the Department of Health and Social Care based on SACN/COMA Dietary Reference Values.

Good dietary sources of zinc include:

• Meat and poultry — beef, lamb, and chicken are among the richest sources of highly bioavailable zinc

• Shellfish — oysters in particular contain exceptionally high levels of zinc

• Dairy products — milk, cheese, and yoghurt provide moderate amounts

• Eggs

• Legumes — lentils, chickpeas, and beans (though bioavailability is lower due to phytate content)

• Nuts and seeds — pumpkin seeds, hemp seeds, and cashews

• Wholegrains — though phytates reduce absorption

For those following plant-based diets, soaking, sprouting, or fermenting legumes and grains can help reduce phytate content and improve zinc bioavailability. The presence of animal protein in a meal also enhances zinc absorption; this is one reason why zinc from animal sources is generally better absorbed than from plant sources.

Zinc supplements and safety

Zinc supplements are widely available in the UK, but caution is warranted. The NHS advises that taking more than 25 mg of zinc per day in supplement form can cause adverse effects, including nausea and vomiting. Prolonged high-dose use can cause copper deficiency, which can itself contribute to hair loss, anaemia, and neurological symptoms. This upper limit is consistent with the tolerable upper intake level established by the European Food Safety Authority (EFSA).

Importantly, zinc supplements can interact with certain medicines. Zinc should be separated from the following by at least two to three hours (or as directed by a pharmacist or prescriber):

• Tetracycline and quinolone antibiotics — zinc can reduce their absorption

• Bisphosphonates (e.g., alendronic acid) — absorption of both may be reduced

• Penicillamine — zinc may reduce its absorption and efficacy

Always inform your GP or pharmacist if you are taking or considering zinc supplements alongside any prescribed medicines.

Supplements should only be taken if a deficiency has been confirmed or is clinically suspected, and ideally under the guidance of a GP or registered dietitian. There is currently no strong evidence that zinc supplementation improves hair growth in individuals who are not deficient.

If you experience any suspected side effects from a supplement or medicine, you can report these via the MHRA Yellow Card Scheme at yellowcard.mhra.gov.uk.

When to See a GP About Hair Loss and Nutritional Deficiencies

See a GP if you experience sudden or diffuse hair shedding, patchy loss, or hair loss alongside systemic symptoms such as fatigue or weight changes, as blood tests can identify underlying nutritional or medical causes.

Hair loss is a common concern affecting both men and women at various life stages, and in many cases it has a benign or reversible cause. However, there are circumstances in which a GP assessment is important — both to identify any underlying cause and to rule out conditions that may require specific treatment.

Consider contacting your GP if you experience:

• Sudden or rapid hair shedding, particularly in large amounts

• Diffuse thinning across the scalp that has developed over weeks to months

• Hair loss accompanied by fatigue, weight changes, or other systemic symptoms

• Patchy hair loss, which may suggest alopecia areata — an autoimmune condition

• Hair loss alongside symptoms suggestive of thyroid dysfunction, such as feeling unusually cold, constipated, or gaining weight unexpectedly

• Concerns about your nutritional intake, particularly if you follow a restrictive diet

Seek prompt medical attention if you notice:

• A painful, inflamed, or pustular scalp, which may indicate scarring alopecia or a scalp infection

• Patchy hair loss with scaling or broken hairs, particularly in children — this may suggest tinea capitis (scalp ringworm), which requires antifungal treatment

• Rapidly progressive hair loss associated with systemic illness

• Any hair loss pattern that appears to be causing permanent scarring — early referral to a dermatologist is important, as scarring alopecias require specialist assessment

A GP can arrange blood tests to investigate possible causes. These may include a full blood count, ferritin (iron stores), thyroid function tests, and other investigations guided by your history and examination findings. Additional tests — such as vitamin D, vitamin B12, folate, a coeliac screen, or inflammatory markers — may be considered depending on clinical context rather than as a routine panel.

Regarding zinc specifically: serum or plasma zinc testing has recognised limitations. Results can be affected by recent infection or inflammation, albumin levels, fasting status, and the time of day the sample is taken. Testing is therefore most useful when there is a clear clinical indication, and results should be interpreted alongside the full clinical picture. Your GP can advise whether zinc testing is appropriate in your case.

Self-prescribing high-dose zinc supplements without confirmed deficiency is not recommended and may cause harm. If a deficiency is identified, your GP or a registered dietitian can advise on appropriate supplementation and dietary changes. In most cases, addressing the underlying nutritional gap leads to gradual improvement in hair density over several months as the hair growth cycle normalises.

For further information, the NHS website, NICE Clinical Knowledge Summaries (CKS), the Primary Care Dermatology Society (PCDS), and the British Association of Dermatologists (BAD) provide reliable, up-to-date guidance on hair loss assessment and management.

Frequently Asked Questions