Often overlooked, zinc is a key player in human development—starting from the earliest stages of life and continuing well beyond childhood. Its influence extends to physical growth, cognitive function, and immune health throughout our lifespan.
Why is this mineral so essential from infancy onward? What are the risks of deficiency, and how can we ensure optimal intake? Let’s dive into the fascinating world of zinc, a quiet yet powerful nutrient that supports our balance and vitality at every age.
Body Stores of Zinc
The human body contains between 2 and 2.5 g of zinc. After iron, it is the trace element found in the highest concentration in body tissues. Skeletal muscles, bones, and the prostate (in men) serve as major reservoirs for zinc, though it is also found in many other tissues and organs: the retina, heart, spleen, lungs, adrenal glands, brain, nails, teeth… In fact, zinc is needed everywhere!
Recommended Intake by Age and Condition
Zinc intake is set at 2 mg per day for infants aged 0 to 6 months and 3 mg for those 7 to 12 months. These values are based on observations of healthy North American infants and their average intake. They represent an “adequate intake” established by authorities, rather than a true “recommended dietary allowance,” which is lacking for this age group due to insufficient scientific data.
For children, the recommended intake remains at 3 mg per day from ages 1 to 3, then increases to 5 mg for ages 4 to 8. A marked increase is observed in preadolescence (ages 9 to 13), with recommendations rising to 8 mg. From ages 14 to 18, sex differences emerge: 9 mg for adolescent girls and 11 mg for adolescent boys.
For pregnant women, the daily recommendation is 11 mg, while lactating women require 12 mg of zinc to meet the enormous physiological needs of their rapidly growing infants.
Zinc: Food Sources, Absorption, Deficiency
The body absorbs 15 to 40% of the zinc present in food. Zinc-rich foods include red meat, certain seafood such as oysters, whole grains, legumes, nuts, and some fortified cereals.
Mild zinc deficiency is common. It can result either from insufficient dietary intake or from poor intestinal absorption. In North America, zinc deficiency is most often observed in pregnant women with infections, children and adolescents, the elderly, and individuals following protein-restricted diets (such as vegetarians).
Zinc and Pregnancy
Zinc status during pregnancy directly impacts fetal development.
A 2016 review of 64 studies found an inverse relationship between maternal zinc intake and the risk of giving birth to a low-birth-weight infant.
Similarly, a 2015 meta-analysis involving more than 17,000 women and their infants revealed a 14% reduction in preterm births with zinc supplementation during pregnancy.
Premature infants born to mothers with adequate zinc levels also showed reduced risk of growth delay, lower vulnerability to infections, and decreased likelihood of developing chronic asthma.
Zinc and Physical Growth
Stunted linear growth and poor weight gain are common features of mild zinc deficiency.
Several studies in young children with significant growth delays have shown that modest zinc supplementation has a positive effect on anthropometric measurements such as height, weight, and weight-for-age scores.
Although the exact mechanisms linking zinc and growth are not fully understood, research suggests that zinc positively influences levels of insulin-like growth factor-1 (IGF-1), a key growth-regulating hormone.
Zinc and Cognitive/Psychomotor Development
Adequate nutrition is essential for brain development, especially during the first 1,000 days of life—a critical window for the growth of all organs and systems, from conception to 24 months of age.
Zinc deficiency may impair cognitive development, leading to problems with attention, learning, behavior, and motor skills. The exact mechanisms remain unclear, but zinc appears to be essential for neuron formation, synapse development, cortical (grey matter) growth, and proper nerve signal transmission.
Optimal maternal zinc status during pregnancy and breastfeeding has been associated with better newborn attention span, greater playfulness and vigor, as well as enhanced motor function development at 6 months of age.
In childhood and adolescence, animal studies have consistently demonstrated zinc-deficiency-related cognitive impairment. While human studies are limited, some evidence suggests improved cognitive function with zinc supplementation.
Zinc and Immune Function
Adequate zinc intake is essential for the development and integrity of both innate immune cells (neutrophils, macrophages, and natural killer cells) and adaptive immune cells (B and T lymphocytes).
According to the World Health Organization (WHO), zinc deficiency is responsible for 13% of all cases of lower respiratory tract infections—mainly pneumonia and influenza—in children under 5.
Zinc also plays a key role in mucosal resistance to infection by supporting antibody production against invading pathogens. As a result, optimal zinc status reduces susceptibility to intestinal infections in children and decreases both the duration and severity of acute childhood diarrhea.
Zinc-Enriched Supplements
Antioxidant, protective, and restorative for all body cells, zinc is a little-known yet indispensable trace element for our health.
Miviton and Miviton Enfant tonics are enriched with zinc.
Which one is best suited for you and your family? Find out!
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