The Healthspan Map · Nutrient

Zinc

Linked to getting too little

Where a shortfall of Zinc is linked — 19 sources.In the order the Map holds them: strongest evidence first. That is a statement about the evidence, not about what matters most.
Nutrient or lever	Direction	Strength	Evidence type	What was found	Source
Zinc	Eat enough of	Emerging	Review / narrative	Zinc deficiency is associated with anemia in some populations.	Zinc & anemia (opens in a new tab)
Zinc	Eat enough of	Emerging	RCT / trial	Zinc deficiency is associated with anxiety; zinc repletion may ease symptoms.	Trace-minerals & anxiety review 2023; zinc RCT (elderly) (opens in a new tab)
Zinc	Eat enough of	Moderate	Established clinical	In older adults, deficiency causes problems with thinking, reasoning and memory.	NIH ODS – Zinc (opens in a new tab)
Zinc	Eat enough of	Emerging	Review / narrative	Zinc participates in energy metabolism and immunity; deficiency can present with fatigue.	Micronutrients for energy/fatigue review (Tardy 2020) (opens in a new tab)
Zinc	Eat enough of	Moderate	RCT / meta-analysis	Depression is associated with lower serum zinc; zinc supplementation reduces depressive symptoms (SMD -0.36).	Swardfager et al. 2013; zinc supplementation meta 2021 (opens in a new tab)
Zinc	Eat enough of	Moderate	RCT / meta-analysis	Depression is associated with lower serum zinc; zinc supplementation reduces depressive symptoms (SMD -0.36).	Swardfager et al., "Zinc in depression: a meta-analysis", Biol Psychiatry 2013 (opens in a new tab)
Zinc	Eat enough of	Moderate	Cohort / observational	Zinc activates the AANAT enzyme (serotonin to melatonin); higher serum zinc is linked to less sleep disturbance.	AANAT literature; NHANES 2011-2016 (opens in a new tab)
Zinc	Eat enough of	Emerging	Systematic review	Zinc supports muscle repair and protein metabolism; low intake is associated with poorer muscle performance.	Nutritional supplements & sarcopenia (opens in a new tab)
Zinc	Eat enough of	Strong	RCT / meta-analysis	Zinc is critical for sperm production and testosterone; in asthenospermic men, zinc supplementation increased sperm volume, motility and total count.	Impact of food & nutraceuticals on fertility (ScienceDirect 2025) (opens in a new tab)
Zinc	Eat enough of	Moderate	RCT / meta-analysis	Low zinc status raises respiratory-infection/pneumonia risk; zinc lozenges shortened cold duration by ~2.25 days.	Zinc supplementation & common-cold duration (PMC7356429) (opens in a new tab)
Zinc	Eat enough of	Strong	Established clinical	Zinc deficiency causes dermatitis (acrodermatitis enteropathica), alopecia and impaired wound healing.	Zinc & skin/wound healing (opens in a new tab)
Zinc	Eat enough of	Emerging	Systematic review	Zinc is part of the reviewed mineral battery for stress; it supports HPA-axis and GABAergic regulation.	EFA/B-vitamin/mineral stress review (McCabe et al. 2017) (opens in a new tab)
Zinc	Eat enough of	Moderate	Review / narrative	Zinc is required for thyroid hormone production and T3-receptor function; deficiency impairs thyroid metabolism.	Minerals & thyroid review (PMC7574993) (opens in a new tab)
Zinc	Eat enough of	Moderate	Cohort / observational	Lower zinc intake was linked to a 44% higher 10-year tinnitus incidence; the cochlea concentrates zinc.	Zinc & tinnitus incidence (opens in a new tab)
Zinc	Eat enough of	Moderate	RCT / meta-analysis	Zinc supplementation improves glycemic markers (HbA1c, fasting glucose, insulin resistance); zinc stabilizes insulin and is anti-inflammatory.	Zinc & glycemic biomarkers meta (opens in a new tab)
Zinc	Eat enough of	Moderate	RCT / meta-analysis	Zinc is a core AREDS ingredient supporting retinal antioxidant defense and slowing AMD progression.	AREDS formula review (PMC7015456) (opens in a new tab)
Zinc	Eat enough of	Moderate	Review / narrative	Zinc is essential for immune-cell development and barrier integrity; deficiency impairs immunity and zinc shortens the common cold.	Zinc & immunity (opens in a new tab)
Zinc	Eat enough of	Strong	Established clinical	Zinc deficiency at any age causes loss of taste and smell, and (with vitamin A) impaired night vision.	NIH ODS – Zinc (opens in a new tab)
Zinc	Eat enough of	Strong	Established clinical	Deficiency causes growth retardation, delayed sexual maturation and, in pregnancy, preterm birth and low birth weight.	NIH ODS – Zinc (opens in a new tab)

Linked to getting too much

Where an excess of Zinc is linked — 7 sources.In the order the Map holds them: strongest evidence first. That is a statement about the evidence, not about what matters most.
Nutrient or lever	Direction	Strength	Evidence type	What was found	Source
Zinc	Don't overdo	Emerging	Mechanistic	Excess zinc induces copper deficiency, which causes anemia.	Zinc excess -> copper-deficiency anemia (opens in a new tab)
Zinc	Don't overdo	Moderate	Established clinical	High-dose zinc causes nausea, vomiting and GI upset.	NIH Office of Dietary Supplements — Zinc (opens in a new tab)
Zinc	Don't overdo	Moderate	Review / narrative	Excess zinc (high-dose supplements, denture creams) depletes copper and causes a reversible myeloneuropathy.	Zinc-induced copper deficiency (opens in a new tab)
Zinc	Don't overdo	Emerging	Review / narrative	Excess zinc can induce copper deficiency and, as antioxidant over-supplementation, may impair rather than help sperm function.	Dietary antioxidants & male infertility – antioxidant paradox (PMC8003818) (opens in a new tab)
Zinc	Don't overdo	Emerging	RCT / meta-analysis	Excess zinc can impair immune function and induce copper deficiency, offsetting benefits — more is not better.	Zinc supplementation & common cold (PMC7356429) (opens in a new tab)
Zinc	Don't overdo	Emerging	Established clinical	Zinc above ~40 mg/day can disrupt hair follicles and induce copper deficiency (itself a cause of hair/skin changes).	NIH Office of Dietary Supplements — Zinc (opens in a new tab)
Zinc	Don't overdo	Emerging	Established clinical	Chronically high zinc impairs immune function and induces copper deficiency.	Excess zinc & immunity (opens in a new tab)