Zinc is element 30, the metal that keeps steel from rusting. The body holds about two grams of it, a little more in men than in women, most of it in muscle and bone, and spends it on hundreds of enzymes at once. Few nutrients are needed in so many places and in such small amounts.
What it does
Wherever cells divide and tissue is built, zinc is in the machinery: it holds the shape of the proteins that read DNA, and it sits in the enzymes that copy it. That is why it matters most where the body renews itself fastest. The skin replaces its outer layer every few weeks and the immune system makes new cells by the billion every day; both run short early when zinc runs short. Wounds heal more slowly without it, taste dulls, and hair and nails, which are nothing but cells pushed out in orderly rows, grow poorly.
Zinc is also part of one of the body’s own antioxidant enzymes, superoxide dismutase, which is the plain reason it protects cells from oxidative stress.
How much, and from where
The reference intake is 10 mg a day; the recommended allowances in the United States are 11 mg for men and 8 mg for women. Oysters hold more than any other food, then beef and other meat. Beans, nuts and whole grains contain zinc too, but with it phytates, which bind the mineral in the gut, so a diet with little or no meat takes in less than its numbers suggest. Coffee itself contributes almost none. The safe upper level for adults is 40 mg a day, and a cup is nowhere near it.
Why it is in our formulas
Four of the ten carry zinc. The Daily, The Social and The Chill have it for the immune system and the protection of cells. Big Hair has it for skin, hair and nails, where it works alongside biotin, silica and nettle.
The form
Zinc is never added as the metal. It comes as a salt, such as zinc citrate or zinc gluconate, and salts of zinc taste sharply metallic, which is why ours is microencapsulated: to keep the mineral stable in the bag, and to keep its taste out of the cup. The compound is named in each formula’s list of ingredients, and the amount per cup, as brewed, on its page.