Sometimes even small minerals in your body can make a big impact -- that's the case when it comes to zinc, a trace mineral that is needed to support a healthy immune system and a number of other body functions. Shellfish, such as oysters, are especially rich sources of zinc. By knowing how much you need on a daily basis, you can stay healthy while enjoying some of the delicacies the sea has to offer.
Shellfish are some of the foods naturally richest in zinc. This is especially true for oysters, which contain 76.3 milligrams of zinc per serving, which is six medium, cooked oysters, according to the Linus Pauling Institute. Oysters aren't the only shellfish source high in this mineral, however. Dungeness crab has 4.7 milligrams of zinc per serving, which is about 3 ounces of cooked crab. Lobsters are also high in zinc, according to the Office of Dietary Supplements.
One of the reasons why you may want to choose shellfish as your zinc source is because the zinc they contain is highly bioavailable. Bioavailability is a term that refers to how well the body absorbs the nutrients you take in. Shellfish have the amino acids cysteine and methionine, which help your body take in more zinc. While foods such as whole-grain breads and beans may be high in zinc, it is not as bioavailable as that of shellfish.
Young adult women need about 8 milligrams of zinc per day, according to the Linus Pauling Institute. That means if you eat even one oyster, you can meet your daily zinc intake. Most women get about 9 milligrams in their daily diets, and if you take a multivitamin, zinc is likely included as well. It is possible to have excess zinc in your body, but this is more likely to occur due to taking supplemental zinc and eating a diet high in zinc on a regular basis. You should limit your daily zinc intake to 40 milligrams, which is the upper tolerable intake level.
While shellfish can boost your daily intake of zinc, shellfish allergy is one of the most common food allergies, according to Beth Israel Deaconess Medical Center. If you have not consumed shellfish such as oysters, lobsters and shrimp in the past, start with a small amount to ensure you are not allergic to shellfish. An allergic reaction typically occurs within two hours, but a reaction can take up to 24 hours up to manifest. Watch for symptoms such as hives, a stuffy nose, swelling, wheezing, nausea, gas or an upset stomach. If you are allergic to shellfish, avoid them -- it's not an allergy you typically "outgrow." Reach for foods high in zinc, such as beef, pork and dark meat chicken and turkey instead if you are allergic.
Rachel Nall began writing in 2003. She is a former managing editor for custom health publications, including physician journals. She has written for The Associated Press and "Jezebel," "Charleston," "Chatter" and "Reach" magazines. Nall is currently pursuing her Bachelor of Science in Nursing at the University of Tennessee.