The link between fish consumption and a healthy heart has long been established, primarily due to marine-based omega-3 fatty acids, specifically eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These powerful nutrients offer a range of cardiovascular benefits, including reducing inflammation, lowering blood pressure, and decreasing blood triglycerides. However, not all fish are created equal. When selecting seafood for heart health, the goal is to maximize the intake of beneficial omega-3s while minimizing exposure to contaminants like mercury.
The Heart-Healthy Power of Omega-3s
Omega-3 fatty acids are a type of polyunsaturated fat that the human body cannot produce on its own. This means they must be obtained through diet. For heart health, EPA and DHA from fatty fish are particularly effective at:
- Lowering triglycerides: High levels of this blood fat increase the risk of heart disease, and omega-3s are effective at reducing them.
- Stabilizing heart rhythm: Omega-3s can reduce the risk of arrhythmias, or irregular heartbeats.
- Slowing plaque buildup: By slowing the accumulation of plaque in the arteries, omega-3s help prevent blood clots and reduce the risk of heart attack and stroke.
- Lowering blood pressure: Consistent consumption of omega-3s can lead to a modest reduction in blood pressure.
Prioritizing fatty fish for maximum benefit
While almost all seafood contains some omega-3s, oily or "fatty" fish contain the highest concentrations. The American Heart Association recommends eating at least two 3-ounce servings of fatty fish per week. The healthiest choices strike an excellent balance between high omega-3 content and low mercury levels, making them safe for frequent consumption.
Top Fish for a Heart-Healthy Diet
When you ask what is the healthiest fish to eat for your heart, several species stand out due to their exceptional nutritional profile and low contaminant risk.
Salmon
One of the most popular and versatile options, salmon is a fantastic source of omega-3s and high-quality protein. Both farmed and wild-caught varieties are heart-healthy, though wild-caught Alaska salmon is often praised for its sustainability and low mercury levels. Canned salmon is also a great budget-friendly option and is packed with calcium when the soft bones are included. To retain the maximum omega-3 content, baking, grilling, or poaching is recommended over frying.
Sardines
These small, inexpensive fish are a nutritional powerhouse. Because of their size, they are very low in mercury. Just one 3-ounce serving of canned sardines can deliver a significant dose of omega-3s, along with high levels of calcium and vitamin D (when eaten with the bones). Sardines can be enjoyed in salads, on toast, or mixed into pasta dishes.
Mackerel
Atlantic or Pacific chub mackerel are excellent sources of omega-3s, protein, and B vitamins. It's crucial to distinguish these smaller mackerel species from larger, high-mercury king mackerel. Choosing sustainably sourced, smaller mackerel ensures a heart-healthy meal without the worry of contaminants. Like salmon, mackerel can be grilled, baked, or smoked.
Herring
A staple in many Nordic diets, herring contains even more omega-3s per serving than salmon or sardines. Often available canned, cured, or smoked, herring is a great addition to a heart-healthy diet. It is also an excellent source of vitamin D and selenium. For the freshest taste, look for it fresh and grill or bake it.
Trout
Freshwater rainbow trout is a close relative of salmon and provides a similar profile of protein and omega-3 fatty acids, along with vitamin D. Its milder flavor makes it a great choice for those who are new to seafood. When sourced from U.S. farms or tank systems, it is generally considered a sustainable, low-mercury option.
Fish to limit or avoid
While the benefits of eating fish are clear, some varieties should be consumed sparingly or avoided due to their high mercury content. As a rule of thumb, larger, predatory fish tend to have higher mercury levels because they have been alive longer and consume many smaller fish, concentrating toxins in their bodies.
- Fish high in mercury to avoid completely:
- Shark
- Swordfish
- King Mackerel
- Tilefish (especially from the Gulf of Mexico)
- Marlin
- Fish high in mercury to limit (especially for pregnant women and young children):
- Bigeye Tuna
- Orange Roughy
- Halibut (Wild-caught Atlantic)
- Canned Tuna: For those who consume canned tuna regularly, it's advisable to choose canned light (skipjack) tuna over canned white (albacore), as it has lower mercury levels.
Fish comparison: Omega-3 and Mercury
| Fish | Omega-3s (EPA+DHA per 3oz serving) | Mercury (FDA Category) | Notes |
|---|---|---|---|
| Atlantic Salmon (farmed) | ~1.83g | Best Choice | Very high omega-3s, widely available. Farmed has slightly more than wild. |
| Wild Alaska Salmon | ~1.57g (average) | Best Choice | Excellent sustainability and low mercury. Canned is also a great option. |
| Sardines (canned in oil) | ~1.19g | Best Choice | High in calcium and vitamin D (with bones). Inexpensive and easy to use. |
| Atlantic Mackerel | ~1.02g | Best Choice | High omega-3s, robust flavor. Ensure you choose Atlantic or Pacific chub, not king mackerel. |
| Freshwater Trout | ~0.84g | Best Choice | Mild flavor, good for those new to seafood. Often sustainably farmed. |
| Canned Light Tuna | ~0.19g | Best Choice | Lower omega-3s than fatty fish, but still a source. Lower mercury than albacore. |
| Canned Albacore Tuna | ~0.44g | Good Choice | Higher omega-3s than light tuna, but also higher mercury. Limit intake, especially for pregnant women. |
Sustainable choices and preparation methods
When making your selection, considering sustainable fishing practices is important for the long-term health of our oceans. Organizations like the Monterey Bay Aquarium Seafood Watch and Oceana provide guides to help you make informed choices.
Just as important as choosing the right fish is preparing it in a healthy way. To maximize benefits and avoid adding unhealthy fats, consider these cooking methods:
- Baking or Broiling: Cooking fish in the oven with herbs, lemon, and a drizzle of olive oil. This preserves nutrients without adding excess fat.
- Grilling: A simple and delicious way to cook fish fillets or steaks, perfect for salmon and trout.
- Poaching or Steaming: These gentle, low-heat methods require no added fat and result in moist, flaky fish.
- Using canned options: Canned fish can be a convenient way to get omega-3s. Choose varieties canned in water to minimize fat, although those in olive oil are also a good choice.
By following these guidelines and incorporating a variety of fatty, low-mercury fish into your diet, you can significantly support your heart and overall well-being. For more information on sustainable options, visit the Monterey Bay Aquarium Seafood Watch guide.
Conclusion
For optimal cardiovascular health, the smartest choice is fatty fish that is low in mercury. Smaller, oilier fish like salmon, sardines, mackerel, and trout are rich in omega-3s and pose minimal risk of contaminants, aligning with the American Heart Association's recommendations. By choosing these options, prioritizing sustainable sourcing, and using healthy cooking methods, you can build a diet that effectively supports your heart and overall health.
