Office of Dietary Supplements Fact Sheet: Re: ZINC Health Risks; NIH

[Guest guest]

Health Risks from Excessive Zinc

Zinc toxicity can occur in both acute and chronic forms.

Acute adverse effects of high zinc intake include:

nausea

vomiting,

loss of appetite,

abdominal cramps,

diarrhea,

and headaches [2 <http://ods.od.nih.gov/factsheets/zinc.asp#en2> ].

One case report cited severe nausea and vomiting within 30 minutes of

ingesting 4 g of zinc gluconate (570 mg elemental zinc) [78

<http://ods.od.nih.gov/factsheets/zinc.asp#en78> ].

Intakes of 150–450 mg of zinc per day have been associated with such

chronic effects as

low copper status, altered iron function, reduced immune function, and

reduced levels of high-density lipoproteins [79

<http://ods.od.nih.gov/factsheets/zinc.asp#en79> ].

Reductions in a copper-containing enzyme, a marker of copper status,

have been reported with even moderately high zinc intakes of

approximately 60 mg/day for up to 10 weeks [2

<http://ods.od.nih.gov/factsheets/zinc.asp#en2> ].

The doses of zinc used in the AREDS study

(80 mg per day of zinc in the form of zinc oxide for 6.3 years, on

average) have been associated with a significant increase in

hospitalizations for genitourinary causes,

raising the possibility that chronically high intakes of zinc adversely

affect some aspects of urinary physiology [80

<http://ods.od.nih.gov/factsheets/zinc.asp#en80> ].

The FNB has established ULs for zinc (Table 3). ***Long-term intakes

above the UL increase the risk of adverse health effects [2

<http://ods.od.nih.gov/factsheets/zinc.asp#en2> ].

The ULs do not apply to individuals receiving zinc for medical

treatment, but such individuals should be under the care of a physician

who monitors them for adverse health effects.