What Type of Fish Is Not Fatty? Exploring Lean Seafood Options

December 8, 2025 •

4 min read

According to the American Heart Association, we should eat fish at least twice a week for heart health. However, not all fish are created equal when it comes to fat content, with certain species, often called white fish, being naturally very lean. Finding out what type of fish is not fatty is key for those prioritizing low-calorie, high-protein meals.

Quick Summary

Lean fish are low in fat and calories but rich in protein, offering a healthy alternative to red meat. This guide details popular low-fat species, compares them with fattier fish, and suggests ideal cooking methods to retain moisture and flavor without added fats.

Key Points

Lean vs. Fatty Fish: Lean fish, often called white fish, store fat in their livers, resulting in very low intramuscular fat and calorie content compared to fattier fish like salmon.
Top Lean Options: The most common types of lean fish include cod, tilapia, flounder, sole, and haddock, all of which are known for their mild flavor and flaky texture.
Nutritional Powerhouse: Lean fish are a fantastic source of high-quality protein, essential B vitamins, and minerals like selenium and iodine, which are crucial for overall health.
Ideal for Weight Management: Because of their low-fat and low-calorie nature, lean fish are a perfect choice for those on weight loss diets.
Gentle Cooking is Key: To prevent lean fish from drying out, use moist-heat cooking methods such as steaming, poaching, or baking in parchment paper.
Consider Sustainability: Choosing sustainably sourced lean fish, like Icelandic haddock or monitored cod stocks, helps support healthy marine ecosystems.
Mindful Mercury Consumption: Leaner fish lower on the food chain, such as cod and tilapia, generally contain lower levels of mercury than larger predatory fish.

Understanding Lean vs. Fatty Fish

Fish can be broadly classified into two categories based on their fat content: fatty (or oily) fish and lean (or white) fish. While both offer significant health benefits, their fat distribution and nutritional profiles differ. Fatty fish, such as salmon and mackerel, store fat throughout their muscle tissue and are rich in omega-3 fatty acids, which are excellent for brain and heart health. Lean fish, conversely, store their fat primarily in the liver, resulting in very low intramuscular fat content, low calories, and high-quality protein. This makes lean fish a top choice for weight management and for those seeking to reduce overall fat intake.

The Health Benefits of Lean Fish

Choosing lean fish offers a variety of advantages for a balanced diet:

High-Quality Protein: Lean fish is an excellent source of complete protein, which is essential for building and repairing muscle tissue, boosting satiety, and maintaining a healthy metabolism.
Low in Calories: With their minimal fat content, lean fish like cod and haddock can have fewer than 100 calories per 100-gram serving, making them ideal for low-calorie diets.
Rich in Micronutrients: Many lean fish are packed with crucial vitamins and minerals, including B vitamins (especially B12), selenium, and iodine, which support thyroid function and overall cellular health.
Versatility in Cooking: Because of their mild flavor and firm texture, lean fish are highly versatile and readily absorb seasonings, making them a great introduction for those new to seafood.

Top Types of Lean Fish to Consider

When looking for fish that is not fatty, several excellent options stand out:

Cod: A flaky, mild-flavored white fish, cod is a staple in many cuisines and exceptionally low in fat. It is also a fantastic source of Vitamin B12 and niacin.
Tilapia: A mild and affordable fish, tilapia is low in fat and high in protein, making it one of the most popular farmed species globally. It works well with various cooking methods.
Flounder and Sole: These flatfish are very lean and have a delicate, slightly sweet flavor. They have very few calories and can be prepared whole or as flaky fillets.
Haddock: Closely related to cod, haddock is another lean, white fish with a slightly sweeter and stronger flavor. Haddock from sustainable sources is a smart choice for low-fat meals.
Halibut: While slightly higher in fat than cod, halibut is still considered a lean fish with a firm, meaty texture. It is a great source of protein and Vitamin B12, but due to moderate mercury levels, consumption should be limited to once a week.

Comparison: Lean vs. Fatty Fish


Feature	Lean (White) Fish	Fatty (Oily) Fish
Fat Content	Very low (typically < 2.5%)	High (can be up to 20%)
Calorie Count	Lower	Higher
Primary Fat Storage	Liver	Throughout muscle tissue
Omega-3 Levels	Lower, but still present	High, rich source of EPA and DHA
Protein Quality	Excellent	Excellent
Flavor Profile	Mild and delicate	More intense, fuller flavor
Best for Dieters?	Excellent for low-fat and low-calorie diets	Recommended for heart and brain health, but higher in calories

Cooking Methods for Lean Fish

Due to their low-fat content, lean fish can dry out easily if not cooked correctly. The best techniques involve moisture to keep the fish tender and flaky.

Best Cooking Methods:

Baking or Steaming in Parchment (En Papillote): This method locks in moisture and infuses the fish with herbs and aromatics.
Poaching: Cooking the fish gently in a liquid like water, broth, or wine keeps it incredibly moist.
Baking: Using a marinade, a squeeze of lemon, or covering the dish can prevent it from drying out.
Sautéing: This method is quick but requires a bit of oil or butter to prevent sticking, and is best for thinner fillets.
Grilling in Foil: Wrapping lean fish in foil with vegetables and a little liquid is a fantastic way to grill without losing moisture.

To Avoid:

High-Heat, Dry Cooking: Grilling or broiling without proper marinating or foil can quickly overcook and dry out lean fillets.
Deep Frying: While a classic for white fish, this method negates the low-fat benefits and adds unnecessary calories.

A Note on Sustainability and Mercury

When choosing lean fish, it's also wise to consider sustainability and mercury levels. Fish low on the food chain, such as cod and tilapia, generally have lower mercury levels. The FDA and EPA offer guidance on safe fish consumption, particularly for vulnerable populations. Sustainable options are often noted by certifications from organizations like the Marine Stewardship Council. You can find more information about making sustainable seafood choices on their official site https://www.msc.org/home.

Conclusion

For those seeking a low-fat protein source, the answer to "what type of fish is not fatty?" lies in lean, white-fleshed fish like cod, tilapia, flounder, and haddock. These species offer high-quality protein and essential nutrients with minimal calories and fat, making them an excellent choice for a healthy diet, particularly for weight management. By utilizing gentle cooking methods like steaming, poaching, or baking, you can enjoy these mild-flavored fish in delicious, healthy meals while reaping their numerous benefits. Balancing your intake of lean fish with occasional servings of fattier fish provides a broad spectrum of nutrients for optimal health.

Frequently Asked Questions

Some of the leanest fish species include cod, haddock, and flounder. They contain less than 2.5% fat by weight and are known for their mild taste and low-calorie count.

The fat content of tuna can vary. Canned light tuna (skipjack) is generally very lean, while other varieties, such as albacore, have a higher fat content and are classified as fatty fish.

Yes, tilapia is a low-fat, high-protein white fish. When sourced responsibly from well-managed farms, it is a healthy and nutritious option. Its mild flavor makes it very versatile for cooking.

To prevent lean fish from drying out, opt for moist-heat cooking methods such as poaching, steaming in parchment paper (en papillote), or baking with a sauce or marinade. These techniques lock in moisture and flavor.

No, they are different but both are healthy. Fatty fish are known for their higher omega-3 content, while lean fish provide higher amounts of other nutrients like iodine and excellent protein with fewer calories. Both are recommended for a balanced diet.

Yes, shrimp is a very low-fat and low-calorie seafood choice. It is high in protein and contains antioxidants, making it a healthy addition to your diet.

The nutritional content can differ. Wild-caught fish may be leaner than farm-raised fish, but this is not always the case. For example, some farm-raised fish, like salmon, can have a higher omega-3 content due to their specific diets.