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Vitamins & Minerals

Zinc

Zinc is an essential trace mineral involved in over 300 enzymatic reactions. It plays critical roles in immune function, protein synthesis, wound healing, DNA synthesis, and cell division. Unlike iron or vitamin D, the body has no dedicated zinc storage mechanism — daily intake is required to maintain adequate levels. Serum zinc reflects recent intake rather than long-term stores.

Optimal Ranges

Clinical (NHS) Range

11-24 µmol/L

µmol/L

Performance-Optimised Range

14-20 µmol/L

µmol/L

The clinical range defines what is considered medically “normal” — broad enough to cover 95% of the population. The performance range reflects where research and clinical experience suggest most people feel and function at their best.

Why It Matters

Why Zinc matters for performance

Zinc is a direct cofactor in testosterone synthesis — the enzyme that converts cholesterol to pregnenolone (the first step in steroid hormone production) requires zinc. Studies show that zinc-deficient men have significantly lower testosterone levels, and supplementation in deficient individuals can raise testosterone by up to 50%. Beyond hormones, zinc is critical for immune function: even mild deficiency increases susceptibility to infections and slows recovery. Active men are at particular risk because zinc is lost through sweat — heavy training can deplete levels significantly.

Symptoms

Signs your levels may be off

Low / Deficiency

  • Frequent colds and slow recovery from illness
  • Loss of taste or smell
  • Slow wound healing
  • Hair loss
  • Low testosterone symptoms (fatigue, low libido)

High / Excess

  • Nausea and vomiting (acute overdose)
  • Copper deficiency (zinc competes with copper absorption)
  • Impaired immune function (paradoxically, at very high doses)

Dietary Sources

Foods that support Zinc levels

Oysters (highest food source — 6x the zinc of red meat)Red meat and lambPumpkin seeds and hemp seedsChickpeas and lentilsDark chocolate (70%+ cocoa)

Supplementation

Evidence-based supplementation

Zinc picolinate or zinc bisglycinate (15-30mg daily) are the best-absorbed forms. Zinc citrate is also well-tolerated. Avoid zinc oxide — poorly absorbed. Take on an empty stomach for best absorption, but if it causes nausea, take with food. If supplementing more than 30mg daily, add copper (1-2mg) to prevent copper depletion — zinc and copper compete for absorption. ZMA (zinc + magnesium + B6) is popular among athletes but evidence for performance benefits beyond correcting deficiency is limited. Don't exceed 40mg daily long-term without medical supervision.

Research

Key study

Zinc status and serum testosterone levels of healthy adults

Prasad AS, Mantzoros CS, Beck FW, et al.

Nutrition (1996)

DOI: 10.1016/S0899-9007(96)80058-X

Related Biomarkers

Hormones

Total Testosterone

Optimal: 20-30 nmol/L

Vitamins & Minerals

Vitamin D (25-OH)

Optimal: 100-150 nmol/L

Vitamins & Minerals

Magnesium (Serum)

Optimal: 0.85-1.0 mmol/L

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Test your Zinc levels

Zinc is included in the Helvy 50+ biomarker panel. Get your results in 5 days with a personalised protocol.

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This content is for educational purposes only and does not constitute medical advice. Your data suggests areas for optimisation, but any concerns should be discussed with a qualified healthcare professional. If your results flag values outside safe ranges, we recommend consulting your GP.