ZINC IN FOCUSNEEDS®

Zinc Summary

Zinc is a mineral that must be obtained in the diet and is required for life. Zinc is a cofactor necessary for the activity of about 100 enzymes, including those in energy metabolism, thyroid function, synapse formation, immune function, wound healing, and blood clotting. Zinc deficiency is both serious and common, especially occurring in individuals with poor nutrition and/or gastrointestinal disease. Zinc deficiency is often suspected due to disorders of the skin, nails, and hair. Other features include mental or cognitive disorders, sensory loss, frequent infections, mouth sores, diarrhea, and loss of appetite. Zinc is an agonist for (turns on) for GABA receptors, one of the chief inhibitory pathways in the nervous system, and an antagonist for (turns off) NMDA glutamate receptors, one of the chief excitatory pathways in the nervous system, which also plays a role in neuroprotection. The combination can lead to abnormal inhibitory–excitatory balance, potentially promoting increased excitatory neurological processes, including hyperactivity, autistic behaviors and possibly neurological regression. Zinc is often recommended for a variety of health conditions including conditions of the gastrointestinal, immunological, ocular, neurological, dermatological, and endocrine systems. Side effects can include nausea at the higher doses commonly used in supplementation.

The Details

What Is Zinc?

Zinc is a mineral that must be obtained in the diet and is required for life.

What Does Zinc Do?

Zinc is a cofactor necessary for the activity of about 100 enzymes. Thus, zinc has wide-reaching effects in the body, including in energy metabolism, thyroid function, synapse formation, immune function, wound healing, and blood clotting.

What Does a Zinc Deficiency Appear As?

Zinc deficiency is a serious and common problem worldwide, affecting over 2 billion people. In addition to a common problem in the developing world, zinc deficiency is not rare in developed countries, especially in individuals with poor nutrition and/or gastrointestinal disease. Zinc deficiency is often suspected due to disorders of the skin (eczema, seborrhea, acne, impaired wound healing), nails (brittle), and hair (thin, sparse). Other features include mental or cognitive disorders (include attention and mood), sensory loss (including blunted taste), frequent infections, mouth sores, diarrhea, and loss of appetite.

What About Zinc’s Use in Disease?

Zinc is often recommended for a variety of health conditions including growth retardation, gastrointestinal conditions (acute diarrhea, ulcerative colitis, peptic ulcers), immunological conditions (frequent infections including the common cold, malaria, AIDS, asthma), eye diseases (macular degeneration, night blindness, cataracts), neurological disorders (ADD/ADHD, autism, Alzheimer, anorexia nervosa), dermatological conditions (psoriasis, eczema, acne, slow wound healing, hair loss), diabetes, and high blood pressure. Some athletes use zinc for improving athletic performance and strength.

Zinc is an agonist for (turns on) for GABA receptors, one of the chief inhibitory pathways in the nervous system, whereas under stimulation may lead to increased hyperactive behaviors in some individuals. Zinc is also an antagonist for (turns off) NMDA glutamate receptors, one of the chief excitatory pathways in the nervous system, which also plays a role in neuroprotection and thus potentially guard against episodes of neurological regression. There is evidence of abnormal inhibitory–excitatory balance in the brain of individuals with some brain disorders, which may be targeted by therapy via effects on GABA and glutamate neurotransmission.

Studies performed to date, the clinical experience of many expert physicians, and the generally benign nature of zinc supplementation, have convinced some experts to offer zinc supplementation to their patients with a wide variety of disease manifestations. Individuals that are more likely to benefit are those who also suffer from chronic diarrhea, vision loss, mouth sores, disease of the skin, nails, and/or hair, frequent infections, reduced inhibitory–excitatory balance (anxiety, hyperactivity, impulsivity, OCD, “autistic” behaviors, etc.), or with a history of regression.

Multiple studies have found a relationship between zinc and ADD/ADHD. Low zinc levels were found in the urine and hair of children with ADHD [PMID 35106229]. A meta-analysis (review) of 21 studies revealed lower blood levels of zinc in ADHD [PMID 34272450]. In a randomized, double blind, placebo-controlled clinical trial in children with ADHD, impulsivity, hyperactivity, and socialization improved on zinc supplementation [PMID 14687872]. In a controlled trial, zinc was found to be superior to placebo as a supplementary medication to methylphenidate based on the Teacher and Parent ADHD Rating Scale [PMID 15070418]. In another controlled study in ADHD of zinc versus placebo with methylphenidate, improvement on zinc was noted in inattention [PMID 31841818]. A meta-analysis of six randomized clinical trials in children “showed a significant effect of zinc supplementation on ADHD total scores” and in inattention scores [PMID 34184967]. Mice fed zinc-deficient diets in early life displayed autism and ADHD-related behaviors such as over-responsivity, hyperactivity, attention deficit, and impairments in vocalization and social behavior, as well as an increased incidence rate of seizures and hypotonia [PMID 24277719]. Studies performed to date, the clinical experience of many expert physicians, and the generally benign nature of zinc supplementation, have convinced some experts to offer zinc supplementation to their patients with ADD/ADHD, autism, and a variety of other conditions.

What Are the Common and/or Important Side Effects of Zinc?

Zinc is considered to be likely safe at doses up to 40 mg a day in adults. Occasionally, nausea can occur at dosages commonly used for supplementation. Additional potential side effects are vomiting, diarrhea, and a metallic taste.

Is There Any Laboratory Testing for Zinc Deficiency?

Laboratory testing can reveal the presence of a zinc deficiency, and this test is indicated in specific situations where zinc deficiency is likely or suspected.

What About Additional Dosing Beyond FocusNeeds®?

The dose of zinc in FocusNeeds® (15 mg) is lower than that is some other products, mostly due to the occasional occurrence of nausea, as well as theoretical concerns of possible toxicity in some people at higher dosing. Therapeutic dosages of zinc typically vary from 15 to 220 mg a day. Thus, you may wish to speak to your health care provider regarding additional zinc supplementation beyond FocusNeeds® if you have one of the conditions for which higher dosing is often recommended.