What is the best fish to eat weekly? A guide to healthy and sustainable choices

According to the American Heart Association, eating at least two servings of fatty fish per week can significantly benefit heart health. Selecting the best fish to eat weekly involves balancing high nutrient content, low mercury levels, and sustainability to maximize the health benefits for you and the planet.

Quick Summary

This guide breaks down how to choose the healthiest fish for your weekly diet, highlighting top choices rich in omega-3s and low in mercury. It covers popular options like salmon and sardines, provides a comparison table for quick reference, and offers advice on preparation methods and sustainable sourcing.

Key Points

• Omega-3 Rich: Salmon, sardines, and mackerel are packed with omega-3 fatty acids essential for heart and brain health.

• Mercury Levels Matter: Choose low-mercury fish like sardines, salmon, and trout, and limit high-mercury options such as shark and swordfish.

• Aim for Two Servings: The American Heart Association recommends eating at least two servings of fish per week for optimal health benefits.

• Consider Sustainability: Look for certifications like MSC or ASC to ensure your fish is sourced responsibly.

• Diverse Your Diet: Mix and match oily fish like herring with leaner options like cod for a variety of nutrients.

• Explore Canned Options: Canned fish like sardines and salmon are convenient, affordable, and nutritious.

Why Eating Fish Weekly Matters

Incorporating fish into your weekly diet is a powerful strategy for improving overall health. Fish, especially fatty varieties, are a primary dietary source of omega-3 fatty acids, specifically eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These essential fatty acids are critical for brain function, heart health, and reducing inflammation throughout the body. The human body cannot produce these fats on its own, so they must be obtained through food. Regular fish consumption has been linked to a reduced risk of heart attacks, strokes, and depression. Beyond omega-3s, fish provides high-quality protein, essential vitamins like B12 and D, and minerals such as selenium and iodine.

The Best Fish Choices: Balancing Health and Sustainability

When determining what is the best fish to eat weekly, you need to consider two main factors: nutritional density and potential contaminants, primarily mercury. The goal is to choose options that offer the most benefits with the least risk.

Oily Fish: The Omega-3 Powerhouses

Oily or fatty fish are the richest sources of omega-3s. The NHS and other health bodies recommend including at least one portion of oily fish in your weekly diet.

• Salmon: A nutritional superstar, salmon is high in both omega-3s and protein. It's widely available and versatile for cooking. Both farmed and wild-caught varieties offer excellent nutritional profiles, though wild-caught can sometimes have higher omega-3s. Choose sustainably sourced options certified by organizations like the Marine Stewardship Council (MSC).
• Sardines: These small, inexpensive fish are incredibly nutrient-dense. A single can of sardines provides ample omega-3s, plus significant amounts of calcium and vitamin D, as you can eat the bones. Their small size means they have very low mercury levels.
• Mackerel: Rich in healthy fats, protein, and selenium, mackerel is an excellent choice. It's important to choose sustainably sourced mackerel, as some populations have faced overfishing.
• Herring: An omega-3 powerhouse, herring also provides significant amounts of vitamin D, B12, and selenium. Like sardines, its smaller size contributes to a low mercury content.

Lean Fish: High Protein, Low Fat

Lean white fish are a great source of protein with a mild flavor, making them perfect for those new to seafood. They still contain omega-3s, but in lower amounts than oily fish.

• Cod: A classic, mild-flavored white fish that's high in protein and low in fat. Cod is an excellent source of vitamin B12. For the most sustainable options, look for Icelandic or Arctic cod caught by longline.
• Trout: A good source of omega-3s, protein, and vitamin D, trout is an excellent choice. Farmed rainbow trout is often a highly sustainable option.

Shellfish and Other Options

• Shrimp: The most popular seafood in the US, shrimp is a low-calorie protein source with antioxidants like astaxanthin. It's also a good source of B vitamins and selenium. Choose options with an Aquaculture Stewardship Council (ASC) certification for sustainability.
• Mussels: Affordable and sustainable, farmed mussels are high in omega-3s, B12, and manganese. They are low-impact shellfish with a rich flavor.

Fish Comparison Table

Fish	Primary Benefit	Omega-3 Level	Mercury Level	Sustainability	Best For...
Salmon	Omega-3s, Protein	High	Low	Varies (check certifications)	Grilling, baking, raw
Sardines	Omega-3s, Calcium, Vitamin D	Very High	Very Low	Generally Good	Salads, toasts, pasta
Mackerel	Omega-3s, Selenium	High	Low	Varies (check source)	Grilling, pan-searing
Trout	Omega-3s, Vitamin D	Medium-High	Low	Good (farmed rainbow)	Baking, pan-frying
Cod	Lean Protein, Vitamin B12	Low	Low	Good (Icelandic/Arctic)	Fish and chips, soups
Shrimp	Lean Protein, Antioxidants	Low	Low	Varies (check certifications)	Stir-fries, salads
Mussels	Omega-3s, Vitamin B12	High	Low	Generally Good (farmed)	Steaming, soups

Avoiding High-Mercury Fish

Certain fish, typically larger predators, accumulate higher levels of mercury. It's best to limit or avoid these, especially for vulnerable populations like pregnant women and young children. Fish to avoid or eat rarely include king mackerel, shark, swordfish, and bigeye tuna. Canned light tuna has less mercury than albacore and can be consumed in moderation, but limit albacore intake to once a week.

How to Incorporate Fish into Your Weekly Diet

• Start with two servings. Aim for the American Heart Association's recommendation of two servings per week, with one being an oily fish.
• Choose diverse options. Alternate between different types of fish to vary your nutrient intake and minimize potential contaminant exposure. Try a fatty fish like salmon one day and a lean fish like cod or shellfish another.
• Experiment with cooking methods. Baking, grilling, and steaming are healthy ways to prepare fish that preserve nutrients. Avoid deep frying to keep fat content low.
• Use canned varieties. Canned sardines and salmon are convenient, cost-effective, and nutritious options for quick meals.
• Buy sustainably. Look for eco-labels like the MSC or ASC to ensure your seafood is responsibly sourced.

Conclusion

While there is no single "best" fish for every person, the top contenders for a healthy weekly diet are oily fish like salmon, sardines, and mackerel, and lean fish such as cod and trout. These options provide an abundance of omega-3 fatty acids, high-quality protein, and other essential nutrients, while maintaining low mercury levels. By focusing on low-mercury, sustainable choices and incorporating a variety of fish into your weekly meals, you can enjoy significant health benefits. The key is balance, diversity, and mindful sourcing to ensure your choices are good for both your body and the planet. For further guidance on sourcing, consider checking resources like the Monterey Bay Aquarium's Seafood Watch.

References

• BBC Good Food. (2024). 10 healthy fish to eat. Retrieved from https://www.bbcgoodfood.com/health/nutrition/healthy-fish-to-eat
• American Heart Association. (2024). Fish and Omega-3 Fatty Acids. Retrieved from https://www.heart.org/en/healthy-living/healthy-eating/eat-smart/fats/fish-and-omega-3-fatty-acids
• Today Show. (2025). What is the Healthiest Fish? The 14 Best Fish to Eat. Retrieved from https://www.today.com/health/diet-fitness/healthiest-fish-to-eat-rcna148820
• Scripps Health. (2025). What Is the Healthiest Fish to Eat?. Retrieved from https://www.scripps.org/news_items/2913-what-is-the-healthiest-fish-to-eat
• Prime Medical. (2023). How Much Fish Should You Eat Per Week. Retrieved from https://prime-medical.com/blog/fitness/how-much-fish-should-you-eat-per-week/

Frequently Asked Questions

How many servings of fish should I eat each week?

The American Heart Association recommends eating at least two servings of fish, especially fatty fish, per week.

Which fish are highest in omega-3 fatty acids?

Fatty fish like salmon, sardines, mackerel, and herring are the best sources of EPA and DHA omega-3 fatty acids.

Is canned tuna a good weekly fish choice?

Canned light tuna is a good option in moderation. Albacore tuna has higher mercury levels, so it should be limited to about one serving per week.

Should pregnant women limit certain types of fish?

Yes, pregnant women should avoid high-mercury fish such as king mackerel, shark, and swordfish. Low-mercury options like salmon and cod are safer choices.

What is the most sustainable fish to eat weekly?

Sustainable choices often include farmed mussels, farmed rainbow trout, and certified options like MSC wild Alaska salmon. Check resources like the Monterey Bay Aquarium's Seafood Watch for the most current information.

How can I reduce my exposure to mercury in fish?

To reduce mercury exposure, eat a variety of fish and prioritize smaller, shorter-lived species like sardines and anchovies, which accumulate less mercury.

Is farmed fish or wild-caught fish better?

Both farmed and wild-caught fish can be healthy options. Farmed fish can have consistent omega-3 levels, while sustainably managed wild fish are often leaner. The key is to choose responsibly sourced fish with proper certifications.