This internal part of the body called meat is rich in nutrients.
In fact, a 3.5-ounce (100-gram) serving of eastern wild oysters provides the following nutrients:
- Calories: 68
- Protein: 7 grams
- Fat: 3 grams
- Vitamin D: 80% of the Reference Daily Intake (RDI)
- Thiamine (Vitamin B1): 7% of the RDI
- Niacin (vitamin B3): 7% of the RDI
- Vitamin B12: 324% of the RDI
- Iron: 37% of RDI
- Magnesium: 12% of the RDI
- Phosphorus: 14% of RDI
- Zinc: 605% of RDI
- Copper: 223% of RDI
- Manganese: 18% of RDI
- Selenium: 91% of RDI
Oysters are low in calories but packed with nutrients, including protein, healthy fats, vitamins and minerals.
For example, a 3.5-ounce (100-gram) serving provides more than 100% of the RDI for vitamin B12, zinc, and copper, and more than 75% of daily selenium and vitamin D needs.
These delicious molluscs are also a good source of omega-3 fatty acids, a family of polyunsaturated fats that play important roles in your body, such as regulating inflammation and keeping your heart and brain healthy.
People whose diets are rich in omega-3 fats have a lower risk of diseases such as heart disease and type 2 diabetes.
Excellent source of important nutrients
- Vitamin B12. This nutrient is essential for nervous system maintenance, metabolism, and blood cell formation. Many people, especially older adults, are deficient in this vitamin.
- zinc. This mineral plays a vital role in immune system health, metabolism, and cell growth. A 3.5-ounce (100-gram) serving of oysters provides over 600% of the RDI.
- selenium. This mineral maintains proper thyroid function and metabolism. It also acts as a powerful antioxidant, helping to prevent free radical damage to cells.
- Vitamin D. Vitamin D is essential for immune health, cell growth and bone health. Many people are deficient in this vitamin, especially those who live in cold climates.
- iron. Your body needs iron to make hemoglobin and myoglobin, proteins that carry oxygen throughout the body. Many people don't get enough iron through diet.
In addition to their various other roles in health, many of these nutrients also provide antioxidant protection.
Selenium, for example, is a powerful antioxidant that helps protect your body from oxidative stress, an imbalance that occurs when excess free radicals are produced.
Oxidative stress has been linked to a range of chronic diseases, such as cancer, heart disease and mental decline.
What's more, zinc and vitamins B12 and D also have antioxidant properties, further enhancing the protective effects of oysters.
Research shows that people who eat a diet rich in antioxidants have a reduced risk of heart disease, diabetes, certain cancers and all-cause mortality.
High quality protein source
They are also a complete protein source, meaning they contain all nine essential amino acids your body needs.
Adding protein sources to meals and snacks can help promote feelings of fullness and promote weight loss.
Protein-rich foods stabilize hunger by increasing levels of hormones that promote satiety, such as peptide YY and cholecystokinin (CCK).
High-protein diets have been shown to be effective at promoting weight loss and leading to greater weight loss than low-fat or high-carbohydrate diets.
Following a high-protein diet may also be beneficial in controlling blood sugar, especially in people with diabetes.
For example, a review of nine studies showed that high-protein diets significantly reduced hemoglobin A1c levels—a marker of long-term blood sugar control—in people with type 2 diabetes.
What's more, a high-protein diet can reduce heart disease risk factors in people with type 2 diabetes.
A review of 18 studies in people with type 2 diabetes found that high-protein diets significantly lowered triglyceride levels - a major risk factor for heart disease.
Contains unique antioxidants
DHMBA is a phenolic compound with powerful antioxidant effects.
In fact, one test-tube study showed that it was 15 times more powerful against oxidative stress than Trolox, a synthetic form of vitamin E commonly used to prevent damage caused by oxidative stress.
Some test-tube studies suggest that the DHMBA in oysters may be particularly beneficial to liver health.
For example, a test-tube study showed that it protects human liver cells from damage and cell death caused by induced oxidative stress.
Scientists hope that DHMBA may be useful in preventing or treating liver disease in the future, but research is currently limited to test-tube studies.
Another test-tube study found that DHMBA reduced the oxidation of LDL (bad) cholesterol. Oxidation of cholesterol is a chemical reaction associated with atherosclerosis (the buildup of plaque in the arteries), a major risk factor for heart disease.
Although these results are promising, more research is needed to determine whether DHMBA is effective against oxidative stress in humans.
May contain bacteria
Eating oyster meat increases the risk of bacterial infection.
Vibrio species—including Vibrio vulnificus and Vibrio parahaemolyticus —can concentrate in filter-feeding shellfish. Eating it raw increases the risk of exposure.
These bacterial infections can cause symptoms such as diarrhea, vomiting, fever, and even more serious conditions such as sepsis, a serious blood infection that can lead to death.
According to the Centers for Disease Control and Prevention (CDC), 100 of the 80,000 people infected with Vibrio in the United States each year die from the infection.
Oysters can also carry norovirus and enteroviruses, which can pose health risks.
Additionally, these molluscs may contain chemical contaminants, including heavy metals such as lead, cadmium, and mercury.
Because of these potential health risks, children, people with compromised immune systems, and pregnant or breastfeeding women should avoid eating raw seafood.
Those who choose to eat oysters should be aware of these potential risks. Currently, despite strict monitoring by state and federal authorities, there is no way to ensure they are safe to eat in their raw form.
That's why major health organizations like the CDC recommend eating only cooked foods.
Oysters are very high in zinc. While this mineral is important for health, consuming too much can be harmful.
While zinc toxicity is often associated with supplements, eating too many oysters too often can have negative health effects, such as lowering levels of the minerals copper and iron that zinc competes with for absorption.
Additionally, people with seafood allergies should avoid eating it.