The best fish to eat for weight loss has lean protein, healthy fats, and essential nutrients that support your metabolism. Choosing meals to include the healthiest fish, like salmon, mackerel, and cod, can help you control your weight.

Fish adds variety and satiety to your meals while supporting your health goals. But individual responses to foods vary based on metabolism, health conditions, medications, and other factors. 

Work with your knownwell care team to determine what eating patterns work best for your specific needs.

Disclaimer: Some fish, such as tilefish, king mackerel, tuna (yellowfin and bigeye), and swordfish, contain high levels of mercury. For most adults, the FDA recommends eating lower-mercury fish like salmon, cod, and sardines 2-3 servings per week. 

If you have mercury sensitivity or specific dietary restrictions, you should consult your clinician about appropriate protein alternatives.

Pregnant, breastfeeding, children, and those with a compromised immune system should skip high-mercury fish like swordfish, king mackerel, tilefish, and bigeye tuna. Yellowfin tuna is a safer choice when limited to 6 ounces weekly. Those with seafood allergies, gout, or iodine-induced hyperthyroidism should consult their physician about fish consumption.

Is fish better than other forms of protein for weight management?

The science behind fish and metabolic health

Fish has an average of 18-20 g of protein per 3.5 oz serving, depending on the species. However, lean fish like flounder provide around 15g, while protein-rich options like sardines have up to 25g of protein per serving.

Protein has a thermic effect of 20-30%, meaning your body uses this percentage of protein's calories during digestion. This process is called the thermic effect of food (TEF).

When you eat high-protein foods, your body naturally burns more calories than it would with carbohydrates or fats.

Omega-3 fatty acids give fish its unique health edge over other proteins. These essential fats may support heart and brain health when consumed as part of a balanced eating pattern. 

Does this mean adding fish to your eating pattern will be a cure-all? No, fish provides valuable nutrients as one component of a balanced eating pattern. 

A registered dietitian can help you choose the best fish for weight loss based on your overall eating habits. Be sure to consult your physician before making any changes to your eating pattern or if you have any nutrition-related concerns.

Consistent, supportive food choices and lifestyle adjustments show the most evidence for long-term weight management. 

What makes fish different from other proteins? 

Fish differ from other proteins because they also pack a wealth of vitamins like vitamin D, B12, and Omega-3 fatty acids. Eating fish can be good for weight control as it’s relatively low in calories, high in protein, and nutrient-dense. 

Fish's high protein content (15-25 g per serving) gives it a satiety factor that may help with portion control, though individual responses vary. Some research suggests protein-rich meals increase feelings of fullness, but consult your clinician about what works for your specific needs.

Fish provides nutrients involved in thyroid function. Fish's omega-3s, iodine, and selenium are nutrients the thyroid needs. But fish doesn’t directly affect the thyroid’s metabolism regulation or treat thyroid disorders. 

Protein-rich fish promotes satiety, which may help you feel satisfied with a smaller portion of meals, though individual satiety responses differ. 

What are the 12 best fish to eat for weight loss? 

We picked the 12 best fish that you can eat for weight control based on their protein and nutritional content, shown in the chart below. 

Different fish species offer varied nutritional benefits and flavor profiles. 

The USDA Database provides these numbers

Note: The omega-3 content listed in the table is for raw or baked fish. Preparation methods significantly affect omega-3 levels - grilling and baking preserve most omega-3s, while deep frying can reduce omega-3 content and add unnecessary calories. For maximum nutritional benefit, choose cooking methods like baking, grilling, steaming, or pan-searing with minimal oil.

The best fish for weight management offers high protein, low calories, and healthy fats. Top picks include salmon, cod, sardines, and tilapia. These fish provide nutrients that support metabolism and appetite control. 

The metabolic support champions

1. Wild Salmon:

• Wild salmon has 1.8 g of omega-3 fatty acids per serving. 
• Preparation advantage: Salmon stays moist and maintains moisture better than lean fish, even when slightly overcooked. You're more likely to enjoy it consistently.
• Cost reality: Wild salmon may cost more than other fish, depending on where you source it from. 

2. Sardines:

• Sardines have 20 g of protein and 1.4 g of omega-3s per 3.5 oz serving. 
• Convenience factor: Pre-cooked, shelf-stable, and ready to eat. No preparation barriers exist.
• Honest truth: Some people find sardines have a stronger flavor than other fish. If you're new to sardines, start with those packed in tomato sauce or olive oil rather than plain water-packed varieties. The added flavors help mask the stronger fish taste. You can also try mashing them into pasta sauces or mixing them with lemon and herbs. 

3. Mackerel:

• Atlantic mackerel is one of the best sources of omega-3s and is low in mercury. Mackerel is an “oily” fish, meaning it tends to be fattier. You might notice a stronger fish flavor. King mackerel is not the same kind of fish and has a high-mercury content, so it is not recommended.
• Preparation tip: Mackerel's rich flavor pairs well with acidic ingredients like lemon or vinegar, fresh herbs like dill or parsley, and warming spices like black pepper or paprika. The acidity helps balance the fish's natural oils.

The lean protein champions

4. Cod:

• Cod delivers 18 g of protein with only 82 calories. It contains less than 1 gram of fat per serving, making it ideal for lean protein goals. 
• Versatility advantage: Cod takes on any flavor profile. You can prepare it in dozens of ways without getting bored.
• Quality tip: Wild-caught and farmed cod have different textures and flavors. Wild-caught tends to be firmer with a more pronounced flavor, while farmed is often milder. Preference varies by individual taste and cooking method.

5. Yellowfin Tuna:

• Yellowfin tuna provides 23 g of protein per serving, which makes it one of the most protein-rich options on our list, alongside sardine.
• Post-exercise benefits: The lean protein profile supports muscle recovery after workouts.
• Convenience options: Fresh tuna steaks or canned tuna both work. For canned options, look for brands that test for mercury levels and choose those packed in water rather than oil to reduce calories. Check labels for sodium content if you're monitoring salt intake. 
• Mercury awareness: Yellowfin tuna contains higher mercury levels than canned light tuna. The FDA recommends limiting yellowfin and bigeye tuna to one serving weekly, but canned light tuna (typically skipjack) can be safely consumed 2-3 times per week due to its lower mercury content. 

6. Halibut:

• Halibut offers 19 g of protein with only 91 calories. The meaty texture satisfies people who prefer substantial portions or typically prefer meat. 
• Cooking considerations: Halibut's thick, firm fillets cook more evenly than thin fish, though like all lean fish, it can dry out if overcooked.
• Price consideration: Halibut tends to be more expensive than everyday fish options like tilapia or cod. The smart budget choices

7. Tilapia:

• Tilapia typically costs less and provides 20 g of protein per serving. It's widely available in most grocery stores.
• Beginner-friendly: The mild flavor works for people who typically don’t include fish in their daily eating pattern. It has a mild flavor that many people who typically avoid seafood find acceptable. 
• Reality check: It has a lower omega-3 content than fatty fish like salmon. 

8. Flounder:

• Flounder contains only 91 calories and less than 2 g of fat per 3.5 oz serving, making it one of the lowest-calorie fish options.
• Local advantage: Often available fresh from coastal areas. Fresh flounder beats frozen for texture.
• Preparation key: Flounder's delicate texture requires gentle cooking. Pan-sear until the fish reaches 145°F internally. The fish should flake easily with a fork at this temperature. Don't rely on timing alone, as fillet thickness varies. 

9. Haddock:

• Haddock provides similar nutrition to cod, often at lower prices. The firm texture maintains its shape and doesn't break apart when simmered in soups and stews. 
• Regional availability: More common in Northeast markets. Look for day boats caught when possible.
• Cooking tip: Cook until the internal temperature reaches 145°F and the fish flakes easily with a fork. 

The flavor enhancers

10. Anchovies:

• Anchovies add umami depth to sauces, dressings, and cooked dishes. When heated, they typically dissolve into the background, contributing savory flavor without a strong fish taste. They provide 20 g of protein and high omega-3s in a tiny package.
• Culinary use: Anchovies add umami depth to many restaurant dishes, like Caesar dressing and pasta sauces. Many diners enjoy these flavors without recognizing anchovies as the source.
• Usage strategy: Think of it as a seasoning, not a main course. A few anchovies enhance entire meals and typically their oily flesh melts away into the background of dishes like pastas. 

11. Sea Bass:

• Sea bass offers restaurant-quality taste and texture. The moderate fat content provides a good omega-3 balance.
• Special occasion fish: Typically priced higher than everyday fish options like tilapia or cod. Sea bass can cost more than the average fish. You might see it on the menu of an upscale restaurant, and people prize it for its buttery flavor. 
• Cooking advantage: Sea bass stays moist and tolerates timing mistakes better than leaner fish. However, not all sea bass species are sustainable choices. U.S.-farmed black sea bass or European sea bass offer excellent flavor and texture while supporting sustainable fishing practices. 
  
  • Chilean sea bass (actually Patagonian toothfish), faces significant overfishing pressure and sustainability concerns.

When shopping, check labels carefully. 'Sea bass' alone doesn't tell you the species, so look specifically for black sea bass or European sea bass to ensure you're making a sustainable choice.

12. Mahi Mahi:

• Mahi mahi provides a firm, meaty texture with mild flavor. It works well for people transitioning from meat-heavy nutrition plans.
• Grilling champion: Holds up perfectly on the BBQ. The thick fillets don't fall apart like delicate fish.
• Seasonal availability: Mahi mahi prices may vary seasonally depending on your location and local fishing seasons. Frozen options provide consistent year-round availability."

Overall, the best fish for weight management delivers 15-25 g of protein per 3.5 oz serving, 70-208 calories per serving (with lean fish under 100 calories), and 0.2-2.0 g of omega-3s depending on the type. Wild salmon, sardines, and cod all fit the bill. 

They help you feel full, support your metabolism, and speed up muscle recovery, making them a smart, satisfying choice for steady weight management.

Is fish good for weight management? 

What research actually shows

Fish hits many key ingredients needed for successful weight management by promoting fullness and offering metabolic benefits through lean protein and omega-3s. 

Fish remains a staple in many traditional eating patterns known for promoting long-term health, such as the Mediterranean eating pattern.

People who adhere to the Mediterranean eating pattern tend to have lower rates of obesity, which research attributes to the eating pattern including fish, olive oil, vegetables, whole grains, and legumes, rather than fish consumption alone. Fish forms one important component of this healthful eating pattern. 

Studies consistently link eating patterns rich in fish to better weight outcomes when combined with other healthy habits.

High-protein foods, including fish, may increase satiety hormones like peptide YY and GLP-1 in many individuals, though responses vary based on metabolism, meal composition, and individual physiology. This signals a feeling of fullness to your brain and reduces hunger. Fish's satiety benefit, however, comes from its protein content rather than being unique to fish. 

Remember that what works for one person may not work for another. Work with your healthcare team to find eating patterns that suit your specific needs. 

The protein content in fish contributes to satiety between meals, though individual appetite responses vary based on many factors. Listen to your body and consult a clinician about how to create a satisfying, balanced nutrition pattern that suits you. 

Your body maintains stable energy levels throughout the day when your insulin functions well, so you may feel fewer cravings or intense hunger spikes after eating high-protein foods like fish. 

Fish vs. other proteins for weight management

The best fish to eat for weight loss provides lean protein, heart-healthy fats, and essential nutrients that support long-term weight management. Fish provides comparable protein to other lean meats (15-25g per serving) while also offering omega-3 fatty acids that chicken and lean beef don't contain. 

Each protein source has different nutritional advantages, like fish for omega-3s, chicken for higher protein per calorie, and lean beef for iron and B12.

A 3.5-oz serving of wild salmon contains about 20 grams of protein, while the same serving of skinless, cooked chicken breast offers 26 grams. Both count as complete proteins, which means they provide all nine essential amino acids your body needs but cannot produce on its own.

Both provide complete proteins, which means they contain all nine essential amino acids your body needs but cannot produce on its own. These amino acids help preserve muscle, support energy, and promote fullness between meals.

While both fish and chicken provide lean protein options, fish offers added benefits that chicken and red meat do not. Omega-3 fatty acids like EPA and DHA appear naturally in many types of fish. These healthy fats support heart health and reduce inflammation.

This makes fish a thoughtful choice for people who want to manage their weight without sacrificing overall wellness.

The best fish to eat for weight management also supports calorie-conscious eating. A 3.5-oz portion of fish varies by type, ranging from 91 calories in flounder to 208 in sardines. Lean white fish typically contains 70-100 calories per serving, while fattier fish like salmon and mackerel range from 140-210 calories. 

A 3.5-oz serving of cooked flounder contains about 91 calories, while a 3.5-oz serving of skinless, cooked chicken breast contains about 128 calories. While flounder is slightly lower in calories, both are lean protein options that fit well into weight management eating patterns

Fish provides complete protein with all essential amino acids, similar to other animal proteins. During weight management, adequate protein intake from sources like fish, poultry, or lean meat helps preserve muscle mass.

Choosing the best fish for weight control means prioritizing food that fuels your body, strengthens your goals, and respects your health.

How many times per week should you eat fish?

The FDA recommends people eat low-mercury fish such as salmon, cod, or sardines 2 to 3 times per week. 

Note that the FDA defines a standard serving as 4 ounces for adults, while this guide uses 3.5 ounces (100 grams) for nutritional comparisons.

For adults: Limit high-mercury fish (yellowfin tuna, bigeye tuna) to one serving weekly. 

Pregnant/breastfeeding individuals and children under 12: Completely avoid high-mercury fish (swordfish, king mackerel, tilefish, bigeye tuna) and limit canned light tuna to 2-3 servings weekly. Yellowfin tuna, while higher in mercury than canned light tuna, can be limited to 6 ounces weekly if desired. 

Adults over 50 and those with kidney issues should discuss mercury limits with their physician.

This gives you enough omega-3s without potentially elevating your mercury risk. 

Serving size: A 3.5oz serving of fish aligns with standard dietary guidelines, though individual needs vary based on activity level, health conditions, and nutritional goals. Consult your dietitian for personalized portion recommendations. 

Timing strategy: Fish provides complete protein for muscle recovery after exercise, with individual needs varying based on workout intensity, body weight, and fitness goals. A registered dietitian can help determine your specific post-workout protein needs. The protein in fish may support muscle recovery and can help you feel satisfied until morning. Post-workout fish meals also provide amino acids for muscle repair.

Connect with knownwell today

Weight management doesn't have to mean deprivation. Finding what works for your body takes time. At knownwell, we are here to guide you through every step of what to eat for weight management. 

Your registered dietitian will provide guidance on the best fish for weight loss that fits into your overall eating pattern. Always consult with your physician regarding any big changes or concerns with your nutrition, especially if you have any health conditions. 

What knownwell offers:

• Personalized nutrition plans tailored to your  journey
• Primary care physicians specializing in metabolic health
• Registered dietitians for medical nutrition therapy and ongoing food guidance
• Compassionate, judgment-free care and practical tips from knownwell clinicians

Ready to get started?

• Virtual visits: Available from home in all 50 states
• In-person clinics: Boston area, Chicago, Dallas/Fort Worth, and Atlanta. 
• Insurance accepted: Most major plans offer coverage.

At knownwell, you'll find a team that understands this journey isn't linear. We're here to support you with evidence-based care that respects your individual needs and goals. 

Our knownwell team of primary care physicians, registered dietitians, and obesity counselors can help map your new nutrition plan, eating approach, and provide you with ongoing supportive food choices. 

You’ll see someone qualified to help identify the best course of action for your individual needs before you get a nutrition plan. 

Book your visit today and take the first step toward sustainable health with knownwell.

If you prefer to visit in person, knownwell’s clinics are located within the Boston area, Chicago, Atlanta, and Dallas/Fort Worth metropolitan areas. 

Frequently asked questions

Is fish good for weight loss compared to chicken?

Both fish and chicken are good for weight loss. Chicken typically has more protein and fewer calories than fatty fish like salmon. However, fish provides unique omega-3 benefits that chicken doesn’t. 

Which fish has the most protein for weight management?

The fish that has the most protein for weight management is yellowfin tuna. Yellowfin tuna leads with 23 g of protein per 3.5 oz serving. Sardines provide 25 g of protein per can. Both have high protein content per serving. 

However, note that yellowfin and bigeye tuna are high in mercury, and the FDA recommends limiting intake of tuna to once per week. Always discuss your nutritional needs with a physician. 

How often should I eat fish for weight management?

You should eat 2-3 servings of low-mercury fish weekly for weight management, according to the American Heart Association. This provides sufficient omega-3s and can contribute to a balanced eating pattern. 

What's the healthiest fish for weight management on a budget?

The healthiest fish for weight management on a budget is sardines. They win on nutrition-per-dollar. They pack protein and omega-3s. Frozen cod and tilapia also offer excellent budget options.

Should I limit fish if I'm taking weight management medication?

You don’t have to limit your fish intake if you’re taking weight management medication. Fish, or any other high-protein meal, provides protein that helps preserve muscle mass, which is especially important when taking medications like GLP-1s. 

The protein content (15-25 g per serving) helps you meet the increased protein needs recommended while on these medications(typically 1.2-1.5 g per kg of ideal body weight daily). However, no evidence suggests fish specifically enhances medication effectiveness. 

Remember, medications like GLP-1s should only be prescribed by your clinician, and consult your clinician to tailor your nutritional needs while on medication.

Can I eat fish every day for better weight management results?

Yes, you can eat fish several times a week for weight management results. Focus on variety and pair fish with vegetables for the best results.

However, daily consumption isn't recommended for all types of fish due to mercury levels. The FDA recommends limiting lower-mercury fish to 2-3 servings per week, and limiting higher mercury fish to one serving per week. Always consult with your physician about your eating patterns, especially if you’re pregnant or breastfeeding.

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