Can You Eat Tuna When You’re Pregnant?

Whether you can eat fish (and seafood in general) during pregnancy is a contentious topic. While many experts cite fears of mercury exposure from eating fish like tuna, it can actually be a great source of nutrients for both you and your developing baby.

The key is to eat the right kind of tuna. Read on to learn exactly what kinds of tuna are safe to eat when you’re pregnant and why you might want to add this fish to your pregnancy diet.

Yes, tuna is generally safe to consume when you’re pregnant. 1 In fact, it’s full of nutrients that support both your health and your baby’s growth during pregnancy.

The key is to look for tuna that doesn’t have much mercury, which is what makes some kinds of seafood unsafe to consume when you’re carrying a child.

What’s the safest variety of tuna to eat?

Generally, canned light tuna is the safest variety to eat. This is because canned tuna comes from fish that don’t live as long, so they haven’t built up the high levels of mercury that make them potentially unsafe (more on this below). 2

To know what kind of tuna you can safely eat, the US Food and Drug Administration (FDA) categorizes fish based on their average mercury levels: 1

Bigeye tuna shares the “choices to avoid” category with other mercury-heavy fish, such as swordfish and marlin.

What about raw tuna?

Beyond mercury, avoid all raw or undercooked fish while pregnant, including tuna found in sashimi (and yes, that also means you can’t eat raw sushi when pregnant).

Raw fish can carry harmful bacteria like listeria, which can lead to fatal infections for pregnant women. If you eat fresh (not canned) tuna, make sure you cook it until it reaches an internal temperature of 145°F (63°C). 3

On that note, even if you’re sure you prepared everything properly, keep an eye out for any symptoms of listeria in your pregnancy (e.g., fever, fatigue, muscle aches, and headache) and let your doctor know if you’re unwell as soon as possible.

Now that you know what kinds of tuna you can safely consume, the next question is how much you can actually eat.

The FDA advises pregnant women to eat 2–3 servings or 8 to 12 ounces of a variety of low-mercury fish (the FDA’s “best choices”) per week. 2

As for “good choices” (albacore or yellowfin tuna), you should limit yourself to just one 4-ounce serving per week. If you eat a serving of albacore or yellowfin tuna, you shouldn’t eat any other fish that week to stay within safe mercury limits. 4

While it’s possible to safely consume tuna when pregnant, it’s not without risks. As mentioned earlier, the primary concern with tuna is mercury.

The dangers of mercury in tuna

Mercury is a heavy metal that occurs naturally, but industrial pollution has increased its levels in our oceans and lakes. As mercury moves further up the food chain, it accumulates in the tissue of fish in a process called biomagnification.

Because tuna are predatory fish that can live for a long time and grow quite large, they tend to accumulate larger amounts of mercury than smaller, shorter-lived fish.

Mercury can cross from the placenta to your baby during pregnancy and negatively impact her developing brain and nervous system. This can potentially lead to: 6

• Learning difficulties
• Delayed motor skill development
• Speech, memory, and attention deficits

What are the signs of mercury poisoning?

Generally, mercury exposure doesn’t immediately cause symptoms unless you ingest very large amounts at once. Symptoms typically show up after long periods of contact, sometimes after decades.

However, it’s still worth knowing the signs of mercury poisoning, such as: 7

• Numbness or dull pain in certain parts of your body
• Tremors
• Blurry or double vision
• Memory loss
• Seizures

Track your diet and overall pregnancy symptoms regularly in your journal or pregnancy tracker app, and get medical attention immediately if you show any of the abovementioned symptoms.

Benefits of eating tuna (safely)

If you choose the right kind of tuna, prepare it correctly, and eat it in moderation, it packs a nutritional punch. You’ll get access to plenty of important nutrients like: 8

• Omega-3 fatty acids (DHA and EPA): Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are important nutrients for your baby’s brain, nervous system, and eye development. A diet rich in these healthy fats may also reduce your risk of preterm birth. 9
• Lean protein: Think of protein as the building blocks for your baby’s tissues and organs. Tuna is an excellent, low-fat source of high-quality protein.
• Iron: This mineral is vital for producing hemoglobin, the protein found in red blood cells that carries oxygen throughout your body and to your baby. Adequate iron intake helps prevent maternal anemia and supports your baby’s brain development.
• Vitamin B12: This maintains your baby’s nervous system and works with folate to prevent certain birth defects. It’s also important for the formation of red blood cells and DNA.
• Vitamin D and selenium: Tuna provides vitamin D, which supports immune function and bone health. You can also get the antioxidant selenium from tuna, which protects cells from damage and supports healthy thyroid function.

When choosing canned tuna, always check the label to see what kind you’re purchasing. This lets you know exactly how much you can safely eat.

Make sure to also:

• Choose low-mercury brands: For extra peace of mind, some brands have taken additional steps to ensure safety. Do some research into brands that are available in your area, looking for companies that test every single fish for mercury.
• Cook tuna thoroughly: Again, only eat fully cooked tuna. Whether you’re grilling a fresh steak or making a tuna melt, ensure it reaches an internal temperature of 145°F (63°C).
• Check local advisories: If you have access to fresh, locally caught tuna (which is less common), be sure to check your local health department advisories for information on mercury levels in those specific waters.

Also, as the saying goes, “there are plenty more fish in the sea,” so don’t rely solely on tuna for your weekly fish intake. Eat various kinds of low-mercury fish, like salmon, sardines, tilapia, and cod, to get a broader range of nutrients.

If the thought of adding tuna to your ever-growing list of foods to avoid during pregnancy makes you shed a tear, fear not. As long as you pick the right kind of tuna with the lowest potential for mercury exposure, it can still be a part of your pregnancy diet in moderation.

Still, if you’re ever in doubt about how much tuna you can safely eat, or have any other questions about your pregnancy diet, you can always chat with your doctor or a registered dietician.