Some fish are unsafe for pregnant women and how to choose safe fish

Fish is a highly nutritious food, providing protein, vitamins, and especially omega-3 fatty acids, which are essential for the brain and vision development of the fetus. However, not all types of fish are safe for pregnant women. Some fish contain high levels of mercury or pose a risk of bacterial contamination, which can negatively affect the health of both the mother and the baby. This article will help expectant mothers understand which types of fish to avoid, which ones to eat, and how to choose fish safely throughout pregnancy.

I. Why should pregnant women be cautious when eating fish?

Although fish is a healthy food, certain types can be harmful if consumed improperly. The main risks include:

Mercury poisoning: Large, long-lived fish such as sharks and swordfish tend to accumulate high levels of mercury. Mercury can damage the nervous system and brain development of the fetus.
Bacterial and parasitic infections: Raw or undercooked fish may contain bacteria, viruses, or parasites that pose health risks to the mother and fetus, leading to food poisoning or developmental issues.
Toxic chemical contamination: Some fish may be exposed to harmful chemicals such as polychlorinated biphenyls (PCBs) and dioxins from polluted environments, which can affect the fetus’s immune and hormonal systems.

II. Types of fish pregnant women should avoid

1. Fish with high mercury levels

Mercury is a heavy metal that can damage the fetal nervous system. Fish with high mercury levels to avoid include:

Shark: A large, long-lived fish that accumulates high levels of mercury.
Swordfish: Contains high amounts of mercury, which can affect fetal brain development.
King mackerel: Unlike smaller mackerel varieties, king mackerel has extremely high mercury levels.
Bigeye tuna: While some types of tuna (such as skipjack tuna) can be eaten in moderation, bigeye tuna contains higher mercury levels.
Tilefish: One of the fish with the highest mercury levels.

The U.S. Food and Drug Administration (FDA) recommends that pregnant women avoid these types of fish to prevent adverse effects on fetal neurological development.

2. Raw or undercooked fish

Raw fish dishes like sushi, sashimi, and ceviche may contain bacteria such as Listeria, Salmonella, or parasites that can cause food poisoning.
Smoked, dried, or pickled fish also pose a higher risk of bacterial contamination, especially if not stored properly.

3. Pufferfish

Pufferfish contains tetrodotoxin, a potent toxin that can cause severe poisoning and even death if not prepared correctly.
Pregnant women should strictly avoid pufferfish due to its high risk of toxicity.

4. Fish that may be contaminated with toxic chemicals

Some fish from polluted waters may be contaminated with PCBs, dioxins, and heavy metals, which can harm fetal development.
Fish from heavily polluted rivers, lakes, or seas may contain these harmful substances.

III. Types of fish pregnant women should eat

Although some fish should be avoided, pregnant women should still include fish in their diet to benefit from omega-3, DHA, and protein. Safe and recommended fish include:

Salmon: Rich in omega-3, which helps with fetal brain development.
Herring: High in healthy fatty acids and low in mercury.
Sardines: A great source of calcium and vitamin D, beneficial for fetal bone development.
Catfish: Low in mercury and safe for consumption.
Tilapia: High in protein, low in mercury, and easy to prepare.

Pregnant women should consume 2-3 servings of fish per week (about 230-340g), choosing low-mercury fish to ensure fetal safety.

IV. Important notes when eating fish during pregnancy

1. Cook fish properly

Always cook fish thoroughly at temperatures above 63°C (145°F) to eliminate bacteria and parasites.
Limit fried or deep-fried fish as excessive oil is unhealthy.

2. Choose fish from safe sources

Buy fish from reputable stores and avoid fish from polluted waters.
If eating canned fish, choose low-sodium options without harmful preservatives.

3. Do not overconsume fish

Even though fish is beneficial, pregnant women should only eat 2-3 servings per week to prevent excessive mercury buildup in the body.

V. Conclusion

Adding fish to a pregnant woman’s diet is essential, but selecting the right type of fish is crucial for the health of both the mother and the baby. Avoid fish with high mercury levels, raw fish, or fish with contamination risks. Instead, opt for omega-3-rich, low-mercury fish like salmon, herring, sardines, and tilapia.

By following these guidelines, expectant mothers can make safe and healthy food choices for a smooth and healthy pregnancy!