Oyster Nutrition Facts

Calories and Health Benefits

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When it comes to oysters, you either love them, or you hate them, or won't even try them. But did you know that oysters are good for you? It's hard to imagine that these small, tasty morsels that don't require any chewing and easily slide down your throat are high in several important minerals and protein. What is easy to imagine, however, is that oysters don't have many calories or grams of fat. With only 43 calories and 1.4 grams of fat (and less than half of gram of saturated fat) per serving—which is a generous six oysters—oysters are an excellent appetizer for those who are watching their weight.

Oysters are available either farmed or wild and are harvested in both the Pacific and Atlantic Oceans. Since farmed oysters are grown in living conditions that are similar to wild oysters, there doesn't appear to be any difference in their nutrition.

Health Benefits

For such an unassuming food, the oyster is packed with nutrition. One serving of oysters has about 5 grams of protein and about 2 grams of carbohydrates. They're also high in calcium, potassium, magnesium, and vitamin B-12, as well as iron and zinc.

Oysters are high in iron, a key mineral in producing hemoglobin, which your body needs to transport oxygen to all of your organs and tissues. An iron deficiency causes fatigue and could lead to anemia.

Zinc is a mineral your body needs for many different biochemical processes to occur and is crucial to the immune system. It assists in cell growth and division, the healing of wounds, and breaking down carbohydrates.

Just about every list of aphrodisiacs includes oysters. While there's no evidence to support the idea that any foods will increase your sexual attraction, it is interesting to note that zinc is essential for men's sexual health, testosterone levels, and sperm production.


Oysters can be eaten raw, cooked, or used in dishes such as oyster stew. Generally, raw oysters are safe to eat, but just as with the consumption of any raw fish or seafood, there is a possibility of food-borne illness.

Raw oysters may be contaminated with Vibrio vulnificus, which is a bacteria related to cholera. Oysters harvested in warm water are more likely to be infected than oysters collected from colder water. This is why there is the saying that you should only eat oysters in months that have the letter "r" in them—the months that don't have an "r" include May, June, July, and August, the warm months when Vibrio contamination is more likely. That was a problem many years ago when oysters weren't tested properly, but today the oysters you buy are safe year round.

If you've been told not the consume raw oysters, you must avoid them. A healthy person who ingests the bacteria may suffer from abdominal pain, vomiting, and diarrhea. However, the infection can be severe in a person who has liver disease or is immunocompromised because the bacteria can get into the bloodstream and cause septicemia, which is fatal about 50 percent of the time.

The only way to kill bacteria in oysters is through cooking. There are myths that adding lots of hot sauce or drinking alcohol while you eat raw oysters will kill the bacteria, but that is not true.

Eating raw shellfish, oysters, in particular, can put you at risk of contracting hepatitis A, a disorder that affects your liver. That's because oysters filter a substantial amount of water, and if that water is contaminated with stool containing the hepatitis A virus, the oyster can become contaminated. But because oysters for purchase are tested, the risk is minimal.

Selection and Storage

When buying oysters, choose fresh oysters that have been harvested and processed according to safety guidelines. (Look for a tag on containers or sacks of oysters.) Throw away any oysters that have broken shells, and tap any open shells with your finger—a live oyster should close its shell when you tap it. If it doesn't close, then throw it away.

Fresh oysters should be refrigerated at 40 F or lower until you serve them or use them in a recipe. When you cook fresh oysters, the shells should open up. Discard any oysters that remain closed.

Preparing Oysters

Oysters are often served raw, usually sitting on its shell. To prepare raw oysters, you'll need to open them up by shucking them (use a thick towel and an oyster shucking knife), or you can buy them already shucked. Oysters can also be smoked, baked, fried (as in crispy oysters Rockefeller), grilled, or used as the featured ingredient in dishes such as oyster stew or oyster-stuffed artichokes.

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