Is it safe for a pregnant individual to consume tuna and salmon, and what are the recommended weekly limits and preparation guidelines to avoid mercury exposure and food‑borne pathogens?

Tuna and Salmon Consumption During Pregnancy

Pregnant women should consume 8-12 ounces per week of low-mercury fish including salmon and canned light tuna, while strictly avoiding high-mercury predatory fish and ensuring all seafood is thoroughly cooked to 145°F. 1

Recommended Fish Intake

Salmon is an excellent choice during pregnancy, providing 2-3 servings per week of omega-3 fatty acids (EPA and DHA) that are critical for fetal brain and retinal development without significant mercury burden. 1 The American College of Obstetricians and Gynecologists specifically recommends 8-12 ounces weekly of low-mercury seafood, with salmon being among the safest and most nutritious options. 1, 2

Tuna Consumption Guidelines

The guidance on tuna requires careful distinction between types:

• Canned light tuna is acceptable within the 8-12 ounce weekly limit for low-mercury fish 1
• White (albacore) tuna must be strictly limited to no more than 6 ounces per week due to moderate mercury content 1, 2
• This distinction is critical because albacore tuna accumulates significantly more mercury than light tuna varieties 1

Research demonstrates that pregnant women often misrecall the specific guidance on tuna limits, with confusion about which type and how much is safe. 3 The key is remembering that albacore/white tuna requires a separate, more restrictive limit than other low-mercury fish.

Fish to Completely Avoid

Eliminate these high-mercury predatory fish entirely during pregnancy: shark, swordfish, king mackerel, and Gulf of Mexico tilefish. 1, 2, 4 Mercury crosses the placenta and damages the developing fetal nervous system, making avoidance of these species non-negotiable. 1, 4

Preparation and Safety Requirements

Cooking Standards

• Cook all seafood to an internal temperature of 145°F to prevent foodborne illnesses including listeriosis 1, 2
• Avoid all raw or undercooked seafood including sushi, raw oysters, and undercooked shellfish 1, 2
• Use non-fried preparation methods such as baking, grilling, or poaching to maximize omega-3 benefits while minimizing saturated fat addition 1

Food Safety Practices

• Wash hands, cutting boards, and utensils thoroughly after contact with raw seafood 2
• Keep uncooked seafood separate from other foods to prevent cross-contamination 2
• These precautions prevent listeriosis and toxoplasmosis, which pose serious risks during pregnancy 2

Diversification Strategy

Vary seafood choices among multiple low-mercury species (salmon, sardines, cod, pollock, shrimp, catfish) to minimize exposure to any single environmental contaminant. 1 This approach is particularly important because while mercury is the primary concern, other pollutants like dioxins and PCBs may be present in fish. 5, 3

Common Pitfalls and How to Avoid Them

Risk Aversion Leading to Inadequate Intake

Research shows that after mercury advisories, pregnant women dramatically reduced fish consumption—including safe varieties—resulting in intakes well below recommended levels. 6, 7 One study found median fish intake among pregnant women was only 1.8 oz/week, far below the 8-12 ounce recommendation. 7 This overcorrection means women miss critical omega-3 benefits for fetal neurodevelopment. 8, 7

The solution: Emphasize that the 8-12 ounce weekly target for low-mercury fish like salmon is safe and beneficial, not a maximum to avoid. 1

Conflating All Fish Species

Many women receive advice to "limit fish intake" without clear guidance on which types are safe versus dangerous. 8, 3 This leads to avoidance of beneficial fish like salmon due to concerns about mercury. 8

The solution: Clearly distinguish between the "eat 8-12 ounces weekly" category (salmon, light tuna, sardines, cod, pollock, shrimp, catfish) and the "completely avoid" category (shark, swordfish, king mackerel, tilefish). 1, 9

Confusion About Tuna Types

Women frequently cannot recall whether the guidance applies to all tuna or specific types, leading either to complete avoidance or inappropriate consumption of albacore tuna. 3

The solution: Provide written reference distinguishing canned light tuna (safe within 8-12 oz weekly limit) from white/albacore tuna (limit to 6 oz weekly). 1

Rationale for These Recommendations

The benefits of adequate fish consumption during pregnancy are substantial: omega-3 fatty acids decrease risk for arrhythmias, thrombosis, and improve endothelial function, while supporting fetal brain and retinal development. 5, 1 However, methylmercury is a potent neurotoxin that readily crosses the placenta. 4 The recommended approach balances maximizing omega-3 intake while minimizing mercury exposure by selecting low-mercury species and avoiding high-mercury predatory fish. 5, 1

For middle-aged and older individuals, the cardiovascular benefits of fish consumption far outweigh mercury risks, but for pregnant women and children, avoiding contaminated fish is the higher priority. 5 This is why the specific species recommendations and preparation guidelines are critical for this population.