What's the best fish to eat for losing weight?

December 10, 2025 •

4 min read

According to the American Heart Association, incorporating fish into your diet at least twice a week can significantly improve heart health and aid in weight management. This is because fish is packed with high-quality protein and essential nutrients that fuel your body's fat-burning processes, making it a key component for those wondering what's the best fish to eat for losing weight.

Quick Summary

This guide explores a variety of lean and fatty fish options, highlighting the high protein content and healthy fats that support metabolism, increase satiety, and reduce inflammation to help with fat loss.

Key Points

Lean White Fish: Choose cod, haddock, or flounder for low-calorie, high-protein meals that promote satiety.
Fatty Fish with Omega-3s: Incorporate salmon, mackerel, and sardines for their healthy fats, which boost metabolism and fight inflammation.
Prioritize Healthy Cooking: Bake, grill, steam, or air-fry your fish to avoid added fats from high-calorie cooking methods like frying.
Eat Fish Twice a Week: Aim for at least two servings of fish per week, with one being an oily fish, to reap maximum benefits.
Vary Your Choices: Mix up your fish types to ensure a broad spectrum of nutrients and to manage mercury intake from larger, high-mercury fish.
Consider Canned Options: Canned tuna and sardines packed in water are budget-friendly, convenient, high-protein choices for quick, healthy meals.

The Weight Loss Power of Protein and Omega-3s

Both lean and fatty fish play a crucial role in a weight loss strategy, but for different reasons. The high protein content in fish is particularly beneficial, as it promotes a feeling of fullness (satiety) and helps increase your metabolic rate, which can lead to greater calorie burn. Protein also helps preserve muscle mass, which is vital for maintaining a higher resting metabolism during calorie restriction.

For weight loss, the most significant benefits come from omega-3 fatty acids, abundant in fatty fish. These healthy fats are known to reduce inflammation and may help with fat oxidation, especially in the abdominal area. Studies have also linked omega-3 consumption to a reduction in the stress hormone cortisol, which, when elevated, can contribute to weight gain, particularly around the midsection.

Lean White Fish: The Low-Calorie Champions

For those focused primarily on calorie control, lean white fish are excellent choices. They provide a high protein punch with very few calories and minimal fat, making them incredibly satisfying without the extra energy. Their mild flavor and flaky texture also make them versatile for various cooking methods.

Top lean fish for weight loss:

Cod: A 3-ounce serving of cooked cod is low in calories and boasts a high protein count. It also provides vitamins B12 and iodine, which support a healthy metabolism.
Haddock: Very similar to cod, haddock is a low-fat, high-protein white fish with a mild taste, perfect for those new to seafood.
Flounder and Sole: These very low-calorie, low-fat flatfish are among the leanest options available, with a cooked portion containing less than 100 calories.
Tilapia: A budget-friendly, mild-tasting fish that is a fantastic source of protein. When prepared healthily, it’s a smart, low-fat addition to your diet.

Fatty Fish: Rich in Healthy Fats

Don't let the name 'fatty fish' deter you. The fat content is comprised of heart-healthy omega-3s, which offer unique weight loss benefits and other health advantages.

Top fatty fish for weight loss:

Salmon: Famously high in omega-3s and protein, salmon supports satiety, regulates fat metabolism, and helps curb cravings.
Sardines: These small, omega-3-packed fish are also rich in calcium and vitamin D, both beneficial for metabolic health. Canned sardines are a convenient and affordable option.
Mackerel: A good source of omega-3s, vitamin D, and selenium. Choose smaller varieties like Atlantic or Pacific mackerel to avoid high mercury content found in larger king mackerel.
Trout: With a milder flavor than salmon, trout is another excellent source of protein, vitamin D, and omega-3s, supporting healthy metabolism.

Comparison: Lean vs. Fatty Fish for Weight Loss

To help you decide, here is a quick comparison of popular fish options based on a typical 3-ounce (cooked) serving:


Fish (3 oz cooked)	Calories (kcal)	Protein (g)	Total Fat (g)	Omega-3s (mg, est.)
Atlantic Cod	90	19	1	300
Tilapia	100	21	2	100
Pink Salmon	140	23	5	1000
Sockeye Salmon	150	22	6	700
Canned Light Tuna (in water)	99	22	1	230
Atlantic Mackerel	134	16	8	1300
Sardines (canned in oil, drained)	150	20	8	1200

Note: Nutritional values can vary based on preparation and species.

Smart Cooking Methods Are Crucial

How you prepare your fish can dramatically impact its calorie and fat content. To maximize weight loss benefits, opt for methods that don’t add unnecessary oils or batter. The following methods are highly recommended:

Baking: Season fish with herbs, lemon, or spices and bake in the oven. This method preserves flavor and nutrients without adding extra fat.
Grilling: Grilling offers a smoky flavor and is a fantastic way to cook fish with minimal oil.
Steaming: A simple, healthy method that locks in moisture and flavor, often used for delicate white fish and shellfish.
Air-Frying: This method can create a crispy texture similar to frying but with just a fraction of the oil.

Beyond Fresh Fillets: Other Smart Choices

Canned Tuna and Sardines: A budget-friendly and quick protein source. Opt for tuna packed in water over oil to save calories. These are also great for meal prep.
Shellfish: Options like shrimp, crab, and scallops are very low in calories and high in protein, making them excellent choices. Just be mindful of high-sodium sauces.

Conclusion

Ultimately, there is no single "best" fish, but a combination of both lean and fatty options offers the most comprehensive weight loss benefits. Lean fish like cod, haddock, and flounder are ideal for low-calorie, high-protein meals that promote satiety. In contrast, fatty fish such as salmon and sardines provide essential omega-3s that boost metabolism and aid in fat burning. By incorporating a variety of fish into your diet and focusing on healthy cooking methods like baking or grilling, you can leverage their powerful nutritional profile to effectively support your weight loss goals. For the most up-to-date guidance on sustainable and healthy seafood choices, consult resources like the Monterey Bay Aquarium's Seafood Watch program: https://www.seafoodwatch.org/.

Frequently Asked Questions

Fatty fish like salmon and sardines are considered among the healthiest due to their high content of omega-3 fatty acids, which aid in fat burning and reduce inflammation.

Lean white fish such as cod, flounder, sole, and haddock are the lowest in calories and fat, making them excellent for calorie-controlled weight loss plans.

Fish is often considered better for weight loss than chicken due to its higher omega-3 content and, in many cases, lower calorie count per gram. The unique fatty acid profile supports metabolism and satiety more effectively.

Studies suggest that oily fish rich in anti-inflammatory omega-3s, like salmon, sardines, and mackerel, can help reduce visceral (belly) fat when combined with diet and exercise.

For weight loss, wild-caught salmon is generally lower in calories and fat than farmed salmon, while still providing ample omega-3s. However, farmed salmon remains a healthy choice and can be more budget-friendly.

Both are great high-protein, lean options. Canned light tuna packed in water offers higher protein density and more omega-3s, making it a slightly better choice for satiety and fat loss, though both are excellent low-calorie options.

Focus on healthy, low-fat cooking methods. Grill, bake, steam, or air-fry fish with herbs, lemon, and spices. Avoid heavy breading and deep-frying to keep calorie counts low.