Shrimp is one of the lowest-mercury seafoods you can eat. With an average mercury concentration of just 0.009 parts per million (ppm), shrimp contains roughly 100 times less mercury than high-risk fish like swordfish or king mackerel. The FDA and EPA both place shrimp in their “Best Choices” category, meaning it’s safe to eat two to three servings per week, even during pregnancy.
How Much Mercury Is in Shrimp
FDA testing of commercial shrimp sold in the United States found a mean mercury level of 0.009 ppm, with some samples registering as non-detectable and the highest sample reaching just 0.05 ppm. For context, the FDA action level for mercury in fish is 1.0 ppm. Even the most contaminated shrimp tested came in at one-twentieth of that limit.
A separate study that tested store-bought shrimp across multiple retail brands found a slightly higher average of 0.02 ppm, with most brands clustering around that number. The highest-testing brand averaged 0.03 ppm, while the lowest came in at 0.004 ppm. Either way, these are trace amounts with no meaningful health risk at normal consumption levels.
Why Shrimp Is So Low in Mercury
Mercury accumulates as it moves up the food chain, a process called biomagnification. Small organisms absorb mercury from water and sediment, and each predator that eats them concentrates it further. Large, long-lived predators like sharks and tuna sit at the top of this chain and accumulate the most.
Shrimp sit near the bottom. They’re small, short-lived, and feed primarily on algae, plankton, and organic debris rather than other fish. Because they don’t eat other predators and don’t live long enough to stockpile mercury in their tissues, the levels stay negligible. This is the same reason other small shellfish like scallops, clams, and crawfish also test low.
Wild-Caught vs. Farm-Raised
There’s essentially no difference. Research comparing U.S. wild-caught shrimp to foreign farm-raised shrimp found nearly identical mercury levels: 0.015 ppm for wild and 0.016 ppm for farmed. Both numbers are so close to zero that choosing one over the other for mercury reasons alone doesn’t make practical sense. Brand-to-brand variation within the same store was actually larger than the wild-farmed gap.
Does Cooking Reduce Mercury in Shrimp
No. Boiling shrimp for up to four minutes had no effect on mercury levels. Unlike some contaminants that break down with heat, mercury binds tightly to the proteins in seafood tissue and stays put through normal cooking. This applies to grilling, sautéing, and other methods as well. The good news is that shrimp’s mercury content is so low to begin with that this doesn’t matter in practice.
Selenium’s Protective Role
Shrimp naturally contains selenium, a mineral that can offset mercury’s harmful effects in the body. Selenium binds to mercury and reduces its ability to cause damage to the nervous system. Research on Pacific coast shrimp found that the selenium-to-mercury ratio was consistently greater than 1, meaning there was more than enough selenium present to counteract whatever tiny amount of mercury the shrimp contained. Health benefit indexes calculated in that study were positive across nearly all samples, reinforcing that shrimp is safe from a mercury standpoint.
Recommended Servings for Pregnancy and Children
Because shrimp falls in the FDA’s “Best Choices” category, pregnant and breastfeeding women can safely eat 8 to 12 ounces per week, which works out to two or three palm-sized servings. This actually aligns with the broader recommendation to eat more seafood during pregnancy for its omega-3 and protein benefits, not less.
Children can eat two servings per week from the “Best Choices” list, with portion sizes scaled to the child’s age and body size. The FDA specifically names shrimp among the lowest-mercury options appropriate for children, alongside salmon, tilapia, pollock, and catfish. For kids, a serving is smaller than for adults, roughly one ounce for children ages 2 to 3, scaling up with age.
How Shrimp Compares to Other Seafood
To put shrimp’s 0.009 ppm in perspective, here’s how it stacks up against commonly eaten seafood:
- Swordfish: 0.995 ppm (about 110 times higher)
- Canned albacore tuna: 0.350 ppm (about 39 times higher)
- Canned light tuna: 0.126 ppm (about 14 times higher)
- Salmon: 0.022 ppm (roughly comparable)
- Scallops: 0.003 ppm (even lower)
Shrimp ranks among the very safest options available. If you’re trying to minimize mercury exposure while still eating seafood regularly, shrimp is one of the best choices on the market, and one of the few proteins where mercury simply isn’t a factor worth worrying about at any realistic portion size.