The Health Benefits of Seafood
Seafood is an exceptional addition to a well-rounded and healthy diet, and its significance in various cultures throughout history is well-founded. Here's why seafood is renowned for its health benefits:
Nutrient-Rich Fish
Fish is considered a superior animal protein source, boasting high levels of lean protein, healthy fats (omega-3 fatty acids), and a host of essential nutrients.
Shellfish Nutrient Bounty
Shellfish, including shrimp, crab, oysters, clams, and scallops, offer a treasure trove of immune-boosting nutrients such as zinc, magnesium, selenium, and vitamin B-12. These nutrients are frequently deficient in the Standard American Diet.
Vitamin D Source for Wintery Climates
Seafood plays a vital role in meeting essential vitamin D requirements, particularly for those residing in cold, wintry climates.
Omega-3 Fatty Acids for Brain and Heart Health
Seafood is rich in beneficial omega-3 fatty acids, which are crucial for maintaining both brain and heart health. These fatty acids are known to reduce inflammation in the body and lower the risk of heart disease, stroke, and Alzheimer's disease. (Hooray!)
Enhanced Cognitive Development
Numerous noteworthy studies have demonstrated that children born to mothers who consumed omega-3 rich seafood during pregnancy exhibited improved cerebral and nervous system functioning. These children also scored higher on intelligence tests, leading to a surge of interest in including seafood in the diets of pregnant women (more on this below!).
So, seafood undeniably offers substantial health benefits. However, it's important to be aware of modern-day health risks, notably the presence of mercury, to make informed decisions when shopping for and enjoying seafood.
Why is it important to shop for healthy seafood?
Seafood is generally considered healthy, but if you choose to eat seafood, there are some important things to know about making sure the particular seafood you're consuming is healthy—both for you and our oceans and lakes. Here's why:
Heavy Metals
Decades of pollution from industrial activity have resulted in toxic contaminants like mercury, cadmium, and PCBs (polychlorinated biphenyls) finding their way into our waterways… and the fish and sea creatures that live there.
When we eat seafood, we're eating these pollutants too. And, needless to say, they're detrimental to our health.
Though there are many other toxic compounds found in seafood as well, heavy metals like mercury are a particular problem.
Mercury is a neurotoxin that can cause fatigue, headaches, memory loss and difficulty concentrating, sleep disturbance, tingling or numbness, and vision problems. And, most significantly, it can stunt fetal and infant brain development (which is why it's so important that pregnant and breastfeeding women limit exposure to mercury in particular).
Food-Borne Illness
Consumption of raw seafood that has not been properly handled and stored can lead to serious food-borne illness. Of course, this is true of other foods too, but raw seafood is particularly common in cuisine like sushi, ceviche, oysters, etc.
Shellfish is one of the most common food allergens, and allergic reactions to shellfish can lead to serious complications. (Not that healthy seafood choices can fix this, but just a note to be aware of, as it can sometimes be confused with food poisoning!)
Overfishing
Global fisheries are threatened by overfishing, improper harvesting methods that result in “by-catch” of unintended species, and climate change. It's essential for the health of our waterways (and our continued consumption of seafood!) to practice sustainable fishing methods.
Aquaculture or “farmed fish” is a possible solution, though there are also some sustainability concerns there as well. Some fish farms cause habitat damage and pollution to the surrounding area, escapes of farmed fish into the wild threaten wild fish populations, and disease among farmed fish can be a problem.
But, despite these very real challenges in sourcing healthy, safe, and sustainably harvested seafood, there are some things we can do to maximize the health benefits of eating seafood while minimizing the risk from pollution, food-borne illness, and overfishing.
Tips for Selecting Healthy, Safe & Sustainable Seafood
When it comes to choosing seafood that is both healthy and environmentally responsible, consider the following factors:
High in Omega-3s and Beneficial Nutrients
- Opt for seafood that is rich in omega-3 fatty acids and other valuable nutrients.
Low in Mercury
- Choose seafood with lower mercury content to minimize health risks associated with heavy metal consumption.
Sustainably Managed or Responsibly Farmed
- Prefer seafood sourced from fisheries that are managed sustainably or from responsible aquaculture practices.
Here's what to keep in mind as you shop for seafood that aligns with these criteria:
Cold-Water Fish
- Cold-water fish, such as salmon, tuna, sardines, and trout, are excellent sources of omega-3s, docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA). These nutrients are essential for heart and brain health and can help maintain adequate vitamin D levels during less sunny winter months.
Mercury Accumulation
- Larger and older fish tend to accumulate more environmental toxins, including mercury. To reduce exposure to these toxins, choose smaller fish lower on the food chain, as they contain less mercury.
Balancing Toxin Exposure
- While we are exposed to environmental toxins through various means, the goal is not to eliminate toxin exposure altogether by avoiding seafood. Instead, it's about balancing the health benefits of eating seafood with the safest options available.
Shellfish and Bacterial Concerns
- Be cautious with shellfish from warm waters, as they are more likely to carry illness-causing bacteria. When consuming raw shellfish, seek options harvested in cold water sources to minimize health risks.
Frozen Seafood
- Most wild-caught fish is frozen at sea, so don't hesitate to choose frozen or "previously frozen" fish, as it is often among the freshest available.
Natural Food Stores
- Natural food stores like Whole Foods or local natural foods co-ops typically adhere to sustainable seafood sourcing standards. When unsure, refer to their policies and labels to make informed seafood selections.
Helpful Tools
- Utilize resources like the Monterey Bay Aquarium's Seafood Watch Guide for recommendations on the best seafood choices and their helpful app for quick reference, especially when trying unfamiliar fish types like sushi. π£
- Look for the Global Aquaculture Alliance's Best Aquaculture Practices label, denoting third-party certification of sustainable aquaculture practices.
The Healthiest Seafood Options
Here's a list of seafood options widely regarded as the healthiest, offering optimal nutrient profiles with healthy fats and low mercury content, while also originating from sustainably harvested sources:
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Wild-Caught Alaskan Salmon: A high-omega-3, low-mercury seafood option, sourced from oceans, lakes, or rivers. For farmed salmon, seek third-party certification of sustainable practices, such as the Global Aquaculture Alliance's Best Aquaculture Practices label.
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Sardines: Rich in healthy omega-3s and vitamin D, sardines are a small fish that primarily feed on plankton, making them among the least contaminated fish. Canned sardines are particularly nutritious, as they include the entire fish—bones, scales, and all. π
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Anchovies: Similar to sardines but smaller and oilier, anchovies are another high-omega-3, low-mercury healthy seafood choice.
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Mackerel: This high-omega-3, low-mercury fish offers excellent health benefits, with one serving providing 100% of the recommended daily value of vitamin D.
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Trout: Sustainably fished rainbow trout is a cold-water lake fish, high in omega-3s, and low in mercury.
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Herring: A popular Nordic fish, herring is also rich in omega-3s and vitamin D. It is commonly found canned, pickled, smoked, and can also be enjoyed fresh.
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Oysters: Nutritional powerhouses, oysters provide 75-100% of the recommended daily value of essential nutrients like zinc, selenium, vitamin D, and B12 in a single serving. Choose oysters from colder-water sources, as warm water oysters are more likely to carry illness-causing bacteria.
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Tilapia: This freshwater fish is typically farm-raised, offering lean protein and low mercury levels, making it a safe and healthy choice.
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Cod: Because cod is lower in fat, it tends to be lower in mercury, as environmental contaminants accumulate in fat. Cod liver oil is a common source of vitamin D and omega-3 fish oil supplements.
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Arctic Char: Similar in appearance to salmon and belonging to the salmon family, Arctic char has a flavor profile closer to trout. Its farming practices often make it a sustainable and low-mercury seafood choice.
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Shrimp: Both farmed and wild U.S. shrimp are sustainable options, offering high lean protein content and low mercury levels.
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Clams: High in protein, iron, magnesium, and potassium while low in mercury, clams are also considered a sustainable seafood choice.
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Tuna: Tuna is rich in omega-3s but can have higher mercury levels, especially larger species higher on the food chain. To balance the health benefits and risks, opt for smaller species like skipjack, commonly used in "chunk light" canned tuna. Yellowfin tuna (also known as ahi) has higher mercury levels but can be consumed in moderation, about once a month. Avoid bluefin tuna, often used in sushi, as it is from a depleted fishery.
Seafood to Avoid
There are certain seafood sources that should be avoided due to their high mercury content and the threat to fisheries. Some of these include:
- Bluefin tuna
- Chilean sea bass
- King mackerel
- Marlin
- Monkfish
- Orange roughy
- Shark
- Swordfish
Safety of Consuming Raw Fish
Uncooked seafood is a prevalent and esteemed component of various global cuisines, from sushi in Japan to gravlax in Sweden and ceviche in Latin America. When handled and stored correctly, raw fish (and select forms of raw shellfish) is generally safe to consume. However, there is a degree of risk associated with food-borne illness if it is not handled and stored properly. It is advisable for pregnant women and individuals with weakened immune systems to refrain from consuming raw seafood due to the heightened risk of severe complications from food-borne illnesses.
Safe Amount of Seafood Consumption
As a general guideline, most individuals can safely include approximately 2-4 servings of seafood in their weekly diet, provided they adhere to the guidelines mentioned earlier, which involve choosing sustainably wild-caught or responsibly farmed seafood with low mercury levels. The American Heart Association recommends a minimum of two servings of fish per week to lower the risk of heart disease and stroke.
Pregnant and nursing women should be particularly cautious regarding their seafood intake. Improperly stored or prepared seafood can cause severe illness, which is why pregnant women are advised to avoid sushi as a precautionary measure. Additionally, pregnant women need to be especially vigilant regarding heavy metals, as they can potentially harm the developing fetus.
Recommended Seafood Intake for Pregnant Women
Pregnant and nursing women are encouraged to consume two servings of high omega-3, low-mercury seafood (such as salmon, sardines, or mackerel) each week. It is also recommended to continue avoiding fish with higher mercury content while breastfeeding since mercury can be transmitted through breast milk.