Yes, in moderation, choosing light over white. Canned light tuna is generally considered safe up to 2 to 3 servings per week while breastfeeding.
Tuna salad for lunch seems like an easy protein win when you are nursing around the clock. Then a well-meaning family member mentions mercury, and suddenly that quick sandwich feels like a potential hazard.
The good news is you do not have to give up tuna while breastfeeding. The better question is which tuna and how much. Agencies like the FDA, EPA, CDC, and NHS have published clear serving limits for nursing mothers, and those guidelines leave plenty of room for safe, nutritious seafood. Here is exactly what the research says about balancing the benefits with the risks.
Why Mercury In Tuna Is A Real But Manageable Concern
Methylmercury is a metal that accumulates in oceans and lakes. Small fish absorb trace amounts, and large predatory fish that eat those smaller fish end up with much higher concentrations in their tissues. That is why fish size matters.
During breastfeeding, a small percentage of the mercury circulating in your body may transfer into breast milk. The goal is not zero exposure — it is keeping your average level low enough that your baby stays well below any concerning threshold. That is doable by choosing tuna varieties with consistently lower mercury levels.
Canned light tuna is typically made from smaller skipjack tuna, which test lower for mercury than larger albacore. Bigeye tuna, often used in sushi, has the highest levels and is the one type experts recommend skipping entirely during breastfeeding. Knowing these three categories makes the rest of the decisions straightforward.
Why “Tuna” Feels Confusing — And How To Tell The Difference
The word “tuna” covers several different species with very different mercury profiles. A single label reading “tuna” does not tell you whether it is high, moderate, or low. Understanding which is which removes the guesswork.
- Canned Light (Skipjack): The lowest mercury option among common tunas. This is the one the FDA places in its “Best Choices” category for 2 to 3 weekly servings.
- Canned White (Albacore): Made from larger albacore tuna, this type has moderate mercury levels and falls into the “Good Choices” category. Stick to one serving per week.
- Fresh Tuna Steak (Yellowfin or Albacore): Moderate mercury. Treat it like canned white tuna — no more than one serving per week.
- Bigeye Tuna (Ahi): The highest mercury tuna and the one to avoid completely while nursing. It is common in sushi and sashimi.
The FDA maintains a simple three-tier chart — Best Choices, Good Choices, and Choices to Avoid — that takes the guesswork out of the seafood aisle once you learn the names on the list.
How Much Canned Tuna Is Safe While Breastfeeding?
The FDA and EPA recommend that breastfeeding women eat between 8 and 12 ounces per week of seafood from the “Best Choices” list. Canned light skipjack tuna qualifies. The CDC points out that choosing smaller fish helps minimize mercury exposure — see the CDC mercury breastfeeding advice for the full background.
| Type of Tuna | FDA Category | Weekly Limit While Breastfeeding |
|---|---|---|
| Canned Light (Skipjack) | Best Choice | 2 to 3 servings (8 to 12 oz) |
| Canned White (Albacore) | Good Choice | 1 serving (max 6 oz) |
| Fresh Tuna Steak (Yellowfin) | Good Choice | 1 serving (max 6 oz) |
| Bigeye Tuna (Ahi) | Avoid | None |
| Sushi-grade Tuna (varies by species) | Depends on species | Check if light, white, or bigeye |
A single serving of fish is about 4 to 6 ounces. Most standard cans of tuna are 5 ounces, so one can of light tuna fits neatly into one serving. If you eat two cans in a week, you are still well within the recommended range for Best Choices seafood.
Tips For Keeping Tuna In Your Breastfeeding Diet
A few simple habits make it easy to enjoy tuna without having to think about mercury every time you open a can.
- Read the label carefully. Look for “chunk light” or “skipjack” rather than “solid white” or “albacore.” That one word tells you the mercury level.
- Know what 6 ounces looks like. A single portion is roughly the size of the palm of your hand. Weighing it once helps you visually estimate later.
- Rotate your seafood choices. Tuna is fine in rotation, but variety naturally limits exposure to any single contaminant while maximizing nutrient diversity.
- Ask about sushi ingredients. If you eat sushi, ask the chef whether the tuna is yellowfin, albacore, or bigeye so you can match it to the serving guidelines.
- Check local fish advisories. If you eat freshwater fish caught by friends or family, look up your area’s advisory since mercury levels vary by water source.
Variety is actually your best ally. Swapping in salmon, sardines, or tilapia a couple of days per week keeps your omega-3 intake high while keeping mercury accumulation low.
What About Fresh Tuna, Oily Fish, And The NHS Advice
Guidance from the UK differs slightly from US recommendations, mostly because of how “oily fish” is defined and tracked. The NHS advises limiting oily fish — which includes fresh tuna, salmon, and mackerel — to 2 portions per week for breastfeeding women. The NHS oily fish limit page explains this is to balance the benefits of long-chain fatty acids with the potential for environmental pollutants.
| Tuna Type | US Guidance (FDA/EPA) | UK Guidance (NHS) |
|---|---|---|
| Canned Light Tuna | 8 to 12 oz per week | No specific limit (not classed as oily fish) |
| Canned White (Albacore) | Max 6 oz per week | Count toward 2-portions oily fish limit |
| Fresh Tuna Steak | Max 6 oz per week | Count toward 2-portions oily fish limit |
Both sets of guidance agree on the bottom line: canned light tuna is the safest way to eat tuna regularly, while white and fresh tuna should be modest treats rather than daily staples. The omega-3 DHA in tuna supports your baby’s brain and eye development, and for most mothers the nutritional benefits of moderate consumption outweigh the small mercury risk.
The Bottom Line
Tuna can fit into a breastfeeding diet without much fuss if you pick the right type and keep portions within the published limits. Canned light skipjack tuna is your safest everyday option, white albacore works once a week, and bigeye is best left off the menu until after you wean.
If your baby seems fussy or you have dietary restrictions, a conversation with your lactation consultant or pediatrician can match the FDA’s fish categories to your own postpartum health needs and your baby’s developmental stage.