Saving Seafood

What type of seafood is healthiest? Here’s what experts recommend.

June 12, 2025 — Are you eating enough seafood?

It’s full of vitamins, minerals and protein, and it’s an excellent source of omega-3 fatty acids, a critical nutrient that our bodies need but can’t produce. Studies suggest that eating fish is good for your brain, eye and cardiovascular health. Health authorities recommend that adults eat at least two servings every week, equivalent to about eight ounces.

Yet 90 percent of U.S. adults eat so little seafood that they fall short of the recommendations. That’s not entirely surprising. Dietitians say that many people don’t know about the health benefits of eating seafood, or they may have concerns about the environmental impact and sustainability of commercial fishing. Some may be worried about exposure to mercury, a neurotoxin that’s found throughout the ocean and that can accumulate in fish. Others may be concerned about the costs.

The seafood landscape can also be confusing. With so many options — from shrimp to salmon to canned tuna — how do you know which ones to eat?

According to experts, the best types of seafood are those that meet three criteria:

  • Relatively low in mercury and high in omega-3 fats.
  • Sustainable.
  • Accessible and affordable.

Here’s what to know about seafood, including the healthiest types — and the ones you should reconsider and avoid altogether.

Why eating seafood can make you healthier

Fish is among the best sources of EPA and DHA, two omega-3 fatty acids that are known to reduce inflammation and promote brain and heart health.

“These types of fats are found in high concentrations in your brain, your eyes and your central nervous system,” said Katherine Zeratsky, a registered dietitian nutritionist at the Mayo Clinic. “They’re called essential fatty acids because we need them — and we have to get them from food.”

In 2020, a meta-analysis of studies that followed more than 900,000 people for up to 30 years found that higher fish consumption was associated with a lower risk of developing heart disease and a lower likelihood of dying from the disease. Another meta-analysis of studies involving roughly 670,000 people found that those who ate the most seafood were less likely to die prematurely from any cause. People who on average ate the equivalent of about a half a serving of fish per day (roughly two ounces) were 12 percent less likely to die early.

The evidence is so compelling that the American Heart Association says that eating one to two servings of seafood per week can reduce the risk of heart disease, strokes and sudden cardiac death, “especially when seafood replaces the intake of less healthy foods.”

Read the full article at The Washington Post

Mercury levels in tuna show little change over five decades, study finds

March 25, 2024 — French researchers have found that mercury levels in tuna have remained relatively unchanged at a relatively high level over the past five decades.

The researchers’ study, published on 21 February and titled “Stable Tuna Mercury Concentrations since 1971 Illustrate Marine Inertia and the Need for Strong Emission Reductions under the Minamata Convention,” revealed mercury levels in the fish remained nearly the same from samples ranging from 1971 to 2022, according to the New York Times.

Read the full article at SeafoodSource

Scientists are tracking the link between pollution, climate change, and rising mercury levels in fish

April 11, 2022 — Eating fish is the most common way people are exposed to mercury — more specifically, methylmercury, a highly toxic organic compound. While low levels of exposure are typically harmless, and fish is a healthy source of protein, its overconsumption can lead to neurological problems, especially for fetuses and young children.

The amount of mercury in the atmosphere has quadrupled since the Industrial Revolution, according to some estimates. The pollution has been largely caused by emissions from coal-fired power plants, but other industries also play a role.

Though mercury levels in water are declining — thanks to decreasing coal use in North America and Europe, and technology that reduces sulfur in smoke stacks — scientists are now discovering that climate change might increase methylmercury levels in fish. That’s because fish are becoming more active with rising ocean temperatures, requiring more food and therefore, ingesting more mercury, according to a 2019 Harvard University study.

Researchers in Delaware and New Jersey are trying to find out where and why mercury levels persist. The research, they say, is part of an effort to manage marine fisheries and inform human health guidelines.

“Understanding how methylmercury accumulates in marine fish will help us identify and control its sources to the ocean, and studying how concentrations of methylmercury vary among fish that people eat will improve guidelines for safe seafood consumption,” said Dr. John Reinfelder, an environmental sciences professor at Rutgers University, who has been studying mercury levels in bluefin tuna populations.

Read the full story at WHYY

Safe Catch charts rapid growth, earns plastic neutral certification

April 21, 2021 — Safe Catch, which tests its tuna and salmon for mercury, is seeing high demand for its products in the U.S. and has plans to expand throughout the country and abroad.

The San Francisco, California-based supplier recently became the first rePurpose Certified Plastic Neutral seafood company via a partnership with rePurpose Global. The organization funds the collection, processing, and reuse of as much plastic waste as it uses across its packaging and operations, Safe Catch said in a press release.

Read the full story at Seafood Source

Everybody knows to avoid tuna when pregnant, right? Not so fast. Eating tuna might actually yield better results, says a large new study.

November 26, 2019 — Eating ocean fish is good for you, but some fish have significant levels of methylmercury which is bad for you, so you should avoid those fish, right? Wrong, says a new study.

Mothers who ate seafood, even when it contained high levels of methyl mercury, had smarter kids than those who didnʻt eat seafood, says the comprehensive, peer-reviewed study.

“Moderate and consistent evidence indicates that consumption of a wide range of amounts and types of commercially available seafood during pregnancy is associated with improved neurocognitive development of offspring as compared to eating no seafood,” it said.

This flies in the face of conventional wisdom, and some medical wisdom. Both the U.S. Environmental Protection Agency and the U.S. Food and Drug Administration recommend against pregnant women eating ahi, over concerns about methyl mercury exposure.

There is no question that thereʻs methylmercury in yellowfin, bigeye and bluefin tuna, and that the amount has been increasing in recent years. There are also significant amounts of mercury in blue marlin and other species.

The Hawai`i Department of Health warns against pregnant women eating any blue marlin, swordfish and shark and recommends severe limits on consumption of tunas.

Read the full story at Raising Islands

Pregnant mothers and children should eat seafood

November 15, 2019 — Two recent studies, Hibbeln et al. 2019 & Spiller et al. 2019, published together in Prostaglandins, Leukotrienes and Essential Fatty Acids (PLEFA), examined the health benefits of consuming seafood during pregnancy. Researchers found that seafood consumption during pregnancy was strongly linked to increased IQ in children.

Thirteen leading dietary scientists spent the last two decades conducting the most thorough review on the subject in history. The research evaluated studies on 102,944 mother-child pairs and 25,301 children.

The findings strongly supported what many consumers already know—seafood is good for you. But the specific measurements to this notion were striking, so much so that one of the authors warned SeafoodNews.com, “There is a lost opportunity for IQ when mothers are not eating enough seafood.”

The study found children gain an average of 7.7 IQ points when mothers ate seafood during pregnancy, compared to mothers that did not eat seafood. Another finding showed that children born from mothers who did not eat seafood during pregnancy were three times more likely to be hyperactive.

Read the full story at Sustainable Fisheries UW

Climate change and overfishing are boosting toxic mercury levels in fish

November 11, 2019 — We live in an era—the Anthropocene—where humans and societies are reshaping and changing ecosystems. Pollution, human-made climate change and overfishing have all altered marine life and ocean food webs.

Increasing  temperatures are amplifying the accumulation of neurotoxic contaminants such as organic mercury (methylmercury) in some marine life. This especially affects top predators including marine mammals such as fish-eating killer whales that strongly rely on large fish as seafood for energy.

Now the combination of  pollution, climate change and overfishing are conspiring together to further contaminate marine life and food webs. This has obvious implications for ecosystems and the ocean, but also for public health. The risk of consuming mercury-contaminated fish and seafood is growing with climate change.

Read the full story at PHYS.org

Pro-seafood scientists push to knock mercury warnings out of US Dietary Guidelines

September 23, 2019 — More than a dozen seafood-loving scientists are working to make the message contained in the US’ next update of its “Dietary Guidelines for Americans” even stronger when it comes to encouraging consumption by pregnant mothers and young children.

Their lengthy research paper, which cites some 40 studies that paint a very positive picture of seafood, is expected to be published within weeks in a peer-reviewed journal. Immediately after, the group plans to share its meta-study with the 2020-2025 Dietary Guidelines Advisory Committee, another 20 academics that make recommendations to the US departments of Agriculture and Health and Human Services (USDA and HHS), about what should go into the document that has the most influence when it comes establishing nutrition policy in the country.

The hope: USDA and HHS altogether strike the current document’s mercury warnings and also the suggestion that seafood consumption be limited to 12 ounces per week from the language.

Read the full story at Undercurrent News

Mercury levels in seafood found to be affected by climate change and ecosystem shifts

August 15, 2019 — Mercury levels in seafood can shift as fish seek new sources of prey and as water temperatures warm due to climate change, according to a recent study.

The new study, published in Nature, illustrates that even as global human-driven mercury emissions are declining, warming oceans and shifting predator-prey relationships caused by human fishing practices could still be major drivers of mercury in seafood.

Read the full story at Seafood Source

Research forms complex picture of mercury pollution in a period of global change

February 15, 2019 — Climate change and the loss of wetlands may contribute to increased levels of mercury concentrations in coastal fish, according to a Dartmouth College study.

The finding implies that forces directly associated with global change — including increased precipitation and land use modifications — will raise levels of the toxic metal that enter the marine food chain.

Estuaries, including coastal wetlands, provide much of the seafood that is harvested for human consumption and also serve as important feeding grounds for larger marine fish.

The study, published in late December in the journal Environmental Pollution, adds to the mounting body of research that indicates a complex relationship between the environment and mercury pollution.

“Estuaries provide habitat for the fish that feed our families,” said Celia Chen, director of the Dartmouth Toxic Metals Superfund Research Program. “It’s important to understand how mercury acts within our environment, particularly under increasing climate and land use pressures.”

The Dartmouth study concludes that higher levels of mercury, and its toxic form methylmercury, are associated with higher organic carbon in coastal waters. The study also finds that this results in higher levels of mercury occurring in fish that frequent these waters.

Read the full story at Science Daily