Zinc Intake Calculator

Zinc is an essential trace mineral involved in more than 300 enzymatic reactions in the human body.
It plays critical roles in immune function, protein synthesis, wound healing, DNA synthesis, cell division, and normal growth.
It is also required for proper senses of taste and smell.

Recommended Dietary Allowance (RDA): Institute of Medicine:

Tolerable Upper Intake Level (UL): do not exceed without medical supervision:

Best dietary sources of zinc:

Oysters vary more than any other food here. In the US Department of Agriculture’s data, 3 oz of cooked Pacific oysters carry about 28 mg, and eastern oysters about 52 mg baked or 67 mg steamed. The 74 mg figure on older tables is breaded and fried eastern oysters. Every one of them is over a day’s need, and most are over the adult upper limit, in a single serving.

Vegetarian and vegan note:

Plant-based zinc sources contain phytates (phytic acid), compounds found in whole grains, legumes and seeds, which bind zinc in the digestive tract and reduce absorption.
Vegetarians and vegans may need 50% more zinc than omnivores to achieve the same absorbed amount.
Soaking, sprouting, and fermenting grains and legumes reduces phytate content significantly.

Zinc deficiency symptoms:

• Impaired immune function, frequent infections
• Delayed wound healing
• Hair thinning or loss
• Loss of appetite, taste, or smell
• Skin lesions or rashes
• Growth retardation in children
• Night blindness

Zinc toxicity (above 40 mg/day chronically):

Excess zinc interferes with copper absorption and can cause copper deficiency.
Symptoms include nausea, vomiting, loss of appetite, abdominal cramps, and reduced HDL cholesterol.
High-dose zinc supplements should only be taken under medical supervision.