Tilefish

Safety Status: Avoid Entirely

Tilefish is a high-risk seafood option that must be strictly avoided during pregnancy.

The U.S. Food and Drug Administration (FDA) and the U.S. Environmental Protection Agency (EPA) place Tilefish from the Gulf of Mexico on their list of “Choices to Avoid” for pregnant individuals, women who may become pregnant, and young children.

Tilefish are deep-water fish that live along the ocean floor. They have a long lifespan, often living up to 35 years, which allows them decades to accumulate the heavy metal methylmercury in their muscle tissues.

Mercury from industrial pollution enters the ocean and is converted by marine bacteria into toxic methylmercury, which bioaccumulates up the food chain. Because tilefish eat crabs, shrimp, and smaller fish, their mercury levels become highly concentrated.

Fetal Development Risks of Methylmercury

Methylmercury is a potent neurotoxin. When consumed during pregnancy, it is easily absorbed by the maternal digestive tract and enters the fetal blood supply via the placenta.

The fetal blood-brain barrier is not fully formed, allowing mercury to enter the developing brain.

Even if a mother feels healthy, high levels of prenatal mercury exposure can cause developmental issues, including:

• Impaired cognitive development and learning disabilities.
• Problems with motor skills, balance, and physical coordination.
• Delays in language acquisition and speech.
• Deficits in visual-spatial processing and attention span.

Safe Seafood Alternatives

Expectant mothers do not need to avoid all fish. Seafood is an excellent source of protein, iron, zinc, and DHA omega-3 fatty acids, which support fetal brain growth. The FDA recommends eating 8 to 12 ounces (2 to 3 servings) per week of low-mercury fish, such as:

• Flounder and Sole: Mild, low-mercury white fish.
• Salmon (Wild-Caught): High in DHA and low in mercury.
• Cod and Pollock: Safe, versatile seafood options.
• Shrimp: A low-mercury shellfish choice.