Cold-smoked salmon, the silky type you find in refrigerated packages labeled “lox” or “nova-style,” is not considered safe during pregnancy. Hot-smoked salmon is safer but still carries some risk unless you heat it to 165°F (74°C) before eating. The core issue is a bacterium called Listeria, which thrives in refrigerated, ready-to-eat foods and poses an outsized danger during pregnancy.
This doesn’t mean you need to avoid salmon entirely. Salmon is one of the best foods you can eat while pregnant, thanks to its omega-3 content and extremely low mercury levels. The key is knowing which forms are safe and which to skip.
Why Cold-Smoked Salmon Is Risky
Cold-smoked salmon is cured and then smoked at just 70 to 90°F, a temperature far too low to kill harmful bacteria. The fish is never fully cooked. That’s what gives it its characteristic soft, almost raw texture, and it’s also what makes it a potential carrier of Listeria monocytogenes.
Surveys of retail smoked fish give a sense of how common contamination is. A large UK survey found Listeria in 17.6% of cold-smoked fish samples, compared to just 3.4% of hot-smoked samples. Swedish data showed similar numbers: 15.5% for cold-smoked, 1.8% for hot-smoked. More recent UK testing from 2014 to 2021 found lower rates (4.7% for cold-smoked, 0.7% for hot-smoked), possibly reflecting improved manufacturing practices, but the gap between the two types remains clear.
Most healthy adults who encounter Listeria either fight it off or experience mild digestive symptoms for a day or two. During pregnancy, the consequences can be severe. Listeria infection is linked to miscarriage, stillbirth, premature delivery, and life-threatening infection in the newborn. Pregnant people are significantly more susceptible to invasive illness, even though their own symptoms are often mild: a low fever, muscle aches, fatigue. Some never feel symptoms at all, which makes the infection easy to miss.
Hot-Smoked Salmon: Safer but Not Risk-Free
Hot-smoked salmon is cooked at higher temperatures during processing, giving it a flaky, opaque texture that looks and feels more like cooked fish. It carries a much lower rate of Listeria contamination than cold-smoked varieties. Still, “much lower” isn’t zero, and both the CDC and the NHS recommend taking an extra step: reheat it until it reaches an internal temperature of 165°F (74°C). At that temperature, Listeria is reliably killed.
If you’re adding hot-smoked salmon to a casserole, pasta bake, or quiche, the cooking process should get it there. Eating it straight from the package, cold, is where the small residual risk comes in.
Which Types of Smoked Salmon Are Safe
The CDC draws a clean line between two categories:
- Avoid: Refrigerated smoked seafood sold in the deli case or refrigerated section. This includes anything labeled “nova-style,” “lox,” “kippered,” “smoked,” or “jerky” that requires refrigeration.
- Safe: Shelf-stable smoked fish in sealed, airtight cans or pouches that don’t need refrigeration before opening. The high-heat processing used to make these shelf-stable eliminates Listeria.
- Safe: Any smoked salmon that’s been cooked into a hot dish, like a casserole, frittata, or baked pasta, reaching 165°F internally.
The NHS gives nearly identical advice: avoid cold-smoked or cured fish (including smoked salmon and gravlax, even in sushi) unless it’s been cooked until steaming hot.
Why Salmon Is Worth Eating During Pregnancy
Salmon is one of the lowest-mercury fish available. Fresh or frozen salmon averages just 0.02 parts per million of mercury, and canned salmon comes in at 0.01 ppm. Both are far below the 0.15 ppm threshold that the FDA uses for its “Best Choices” category, which recommends two to three servings per week. You’d have a hard time eating enough salmon to approach concerning mercury levels.
What salmon does offer in abundance is DHA and EPA, the omega-3 fatty acids critical to fetal brain, nervous system, and eye development. A 6-ounce serving of cooked wild Atlantic salmon provides roughly 3,130 milligrams of combined DHA and EPA. Farmed Atlantic salmon is even higher at about 3,650 milligrams. Even a small 3-ounce can of salmon delivers around 1,200 milligrams. These numbers make salmon one of the most efficient ways to get omega-3s from food.
The goal isn’t to avoid salmon during pregnancy. It’s to eat it in forms that don’t carry Listeria risk: baked, grilled, poached, pan-seared, canned, or smoked and then cooked to 165°F.
What to Watch for if You Already Ate It
If you’ve already eaten cold-smoked salmon, there’s no need to panic. The overall odds of any single serving causing infection are low. But it helps to know the timeline. Intestinal symptoms from Listeria, things like diarrhea, nausea, and cramps, typically show up within 24 hours and resolve in one to three days. The more serious invasive form of the illness usually develops within two weeks, with symptoms like fever, muscle aches, and fatigue that can resemble the flu.
Because symptoms in pregnant people are often mild or absent, paying attention to even a low-grade fever or unusual fatigue in the days following exposure is worthwhile. Listeriosis is treatable with antibiotics when caught early, and early treatment significantly improves outcomes for both the pregnancy and the baby.