Zinc

Zinc is a mineral your body needs in small amounts to support your immune system, help wounds heal, enable normal growth, and maintain your sense of taste and smell. Most people get enough zinc from a balanced diet that includes meat, shellfish, legumes, and nuts. Low zinc levels can make you more prone to infections and slow healing, while too much zinc—usually from over-supplementation—can interfere with copper absorption and cause other health problems. Blood zinc tests can be affected by many factors such as time of day, recent illness, or low protein levels, so your doctor will consider these alongside your symptoms and diet when interpreting your result.

When elevated: Elevated serum zinc (hyperzincemia) is most commonly associated with excessive supplementation or occupational exposure rather than dietary intake alone. Chronic zinc excess can competitively inhibit copper absorption, leading to copper deficiency, sideroblastic anemia, and neurological dysfunction including myelopathy. Acute zinc toxicity may cause gastrointestinal symptoms, nausea, and vomiting. When low: Low serum zinc is associated with impaired immune function, increased susceptibility to infections, delayed wound healing, growth retardation in children, hypogonadism, dermatitis, alopecia, and impaired taste and smell (dysgeusia/anosmia). Severe deficiency can cause acrodermatitis enteropathica and profound immune suppression. Marginal deficiency may be subclinical but still contribute to increased infection risk and poor growth outcomes.

Zinc supports immune function and wound healing—both critical during heavy training when immune stress increases and minor cuts or muscle damage occur. Active individuals who sweat heavily or follow restrictive diets (vegetarian, low-calorie) may have lower zinc status and could benefit from monitoring, as deficiency can impair recovery and increase infection risk.