Oysters for Health
Oysters have been consumed by humans for thousands of years. They are part of a small group of foods that people either love or hate, mainly due to their slimy texture and gray phlegm-like appearance. But these strange-looking mollusks, aside from being a delicacy all over the world when served raw, actually have some pretty impressive health benefits.
There is increasing evidence that neanderthals and cave-dwelling people were taking advantage of oysters as a food source. However, it was not until the late 1700s and into the 1800s that oyster consumption really took off. At first, oysters were consumed mostly by the wealthy population. But as the farming practices became more developed into the 1900s, oysters became part of the everyday diet. If you were in New York City it was impossible to turn a corner without running into someone selling oysters from a cart on the sidewalk corner. This led to New York becoming the world’s largest producer of oysters for a short period of time, after which overharvesting and pollution lead to a depletion of the oyster supply.
Oysters are bivalves, which is a group of mollusks that create their own shell and breathe through gills. Bivalves also use their gills to eat, filtering tiny particles out of the water. Because of the way they eat, bivalves and in particular oysters, are very beneficial to the water they live in. Oysters help to purify the water by removing organic nutrients, and when put into a habitat with seaweed and fish they create a water purification system called integrated multi-trophic aquaculture.1 And with each oyster able to purify as many as 50 gallons of water per day, it is amazing to think about what multiple colonies of oysters are able to do for our water systems.2
Oysters have become such a big part of our diets, that in 1979 a researcher by the name of Standish Allen created an oyster that was able to grow larger and faster than the oysters found in the wild. These oysters are triploids, which means they have three sets of chromosomes, compared to two sets in wild oysters. This makes the oysters extremely popular for commercial oyster producers. Not only do they grow faster and larger, they are also sterile. A common problem with oysters is that during the summer months they are spawning, so their flavor is weak and watery since they are using all their energy to reproduce. This is one of the reasons the R-month rule was created for eating oysters. The R-rule states that you should not consume oysters during months that do not contain the letter R (May, June, July, August), the rule likely started when modern refrigeration was only a concept and the oysters were not easily kept at a cold, safe temperature during the summer months but has continued due to the spawning schedule of most oysters.3
While there are hundreds of varieties of oysters, there are only five species that these varieties belong to. The varieties are Atlantic, Pacific, Olympia, European flat, and Kumamoto.4,5
Atlantic oysters are the most common oysters eaten in America, they live in the eastern United States from Maine all the way down to Alabama and the Gulf of Mexico. Atlantic oysters tend to be brinier than the other varieties and they have a raindrop shaped shell.
Pacific oysters, which are also called Japanese oysters, are found in the Pacific Ocean and typically farm-raised. They have a slight fruit flavor and an unmistakable creaminess. Compared to Atlantic oysters, they have a rough and fluted shell.
Olympia oysters are native to the Pacific Northwest and are found almost exclusively in the Puget Sound. They were almost completely wiped out due to pollution during the 19th century. These oysters are some of the smallest, with a very intense flavor.
European flat oysters are native to France, which is where one of the most common varieties, Belon, got its name. They are found in both the Northeastern and the Northwestern United States. Their flavor is a little metallic with a hint of lemon.
Kumamoto oysters are native to Japan but were introduced to the US in the mid-1900s. They are small and have a sweet, almost fruity flavor. You can find kumamoto oysters in the Pacific Northwest, they are one of the most widely enjoyed oysters.
Oysters have become increasingly popular in the United States over the years, with new raw bars and oyster farms showing up all over the place.
Oysters have many health benefits. They are a great source of calcium, iron, zinc, and protein. This makes them a great choice for pescatarians (some vegans even argue that it is OK to eat oysters because they do not feel pain like other animals). Their zinc content has garnered them a reputation as an aphrodisiac, but the research is still out on whether or not there is any actual increase in sexual performance or desire, it may just be a case of the placebo effect.
Oysters are a great source of protein, especially due to the fact that they are low in calories and are a good source of healthy fats such as omega-3s. When you pair this protein boost with the many vitamins and minerals oysters provide, you’ve got a nutritional powerhouse.
In addition to being good for our bodies, oysters are also good for the environment. In addition to purifying the water, oyster shells can also be used as a fertilizer. The calcium they contain is an important part of gardens because it helps plants grow strong and balances the pH levels in the soil. You can purchase oyster shell fertilizer, or better yet you can add crushed oyster shells from your next party to your compost pile for an added calcium boost.
Oysters are a great source of many important vitamins and minerals, which makes them a great thing to add to your healthy diet. And while some people may be turned off solely by the appearance, flavor, or texture of oysters we suggest giving them another try. There are so many different varieties and preparation methods of oysters available, perhaps you have not found your perfect oyster yet.
1. "What is a Bivalve Mollusk?" National Ocean Service. National Oceanic and Atmospheric Administration, n.d. Web.
2. Niemark, Jill. "Why the Southeast Could Become the Napa Valley of Oysters." NPR: The Salt. NPR, 27 Jan, 2016. Web.
3. Fincham, Michael W. "Trials & Errors & Triploids - Odyssey of an Oyster Inventor." Chesapeake Quarterly Volume 9 Number 2. Maryland Sea Grant, June 2010. Web.
4. "Types of Oysters - Oyster Varieties." Berkeley Wellness - University of California. Remedy Health Media, 17 Aug. 2015. Web.
5. Jacobsen, Rowan. "What Kind of Oyster Eater are You?" The Oyster Guide. Rowan Jacobsen, n.d. Web.