What Seafood Is Not Fattening? The Ultimate Guide to Lean Choices

October 15, 2025 •

2 min read

A 3-ounce cooked serving of cod contains only about 70 calories and less than one gram of fat, making it an excellent choice for anyone wondering what seafood is not fattening. For those aiming to manage their weight, choosing lean seafood is a powerful strategy due to its high protein content and low-calorie profile.

Quick Summary

Seafood is low in calories but high in protein, which promotes satiety and aids weight control. Lean options like cod, shrimp, and specific tuna varieties are highly beneficial, especially when prepared with healthy cooking methods like baking or grilling. Controlling portion sizes and avoiding calorie-dense additions are key for success.

Key Points

Lean White Fish: Opt for cod, haddock, flounder, and tilapia, which are very low in fat and calories while being high in protein.
Protein and Satiety: The high protein content in seafood helps you feel full longer, which is vital for effective weight management and controlling appetite.
Smart Cooking Methods: Always choose healthy cooking methods like baking, grilling, steaming, or poaching to keep your meal low in calories. Avoid deep-frying and heavy sauces.
Nutrient-Rich Shellfish: Shellfish like shrimp, scallops, and crab are excellent, low-fat protein sources that also provide essential minerals and vitamins.
Omega-3 Benefits: Fatty fish like salmon, though higher in calories, provide healthy omega-3 fats that support metabolism and heart health, contributing positively to weight control.

The Leanest Seafood Options

Choosing the right type of seafood is key to a non-fattening meal. Different species offer varying levels of fat and calories, with lean, white-fleshed fish and low-fat shellfish being ideal for weight management.

Lean White Fish: Very Low in Fat

These fish are known for minimal fat and mild flavor.

Cod: Very low in calories and fat, high in protein. A 3-ounce cooked serving has about 70 calories and 0.7 grams of fat.
Haddock: Similar to cod, mild and flaky.
Flounder and Sole: Among the lowest-calorie fish, around 60-70 calories per 100 grams.
Tilapia: Popular and affordable, very low in fat.
Mahi-mahi: Lean, firm, and flavorful.
Alaska Pollock: High in protein and low in fat.

Low-Calorie Shellfish

Excellent for low-calorie, high-protein diets, most shellfish are naturally low in fat.

Shrimp: Low in calories and fat when boiled or steamed, provides 24 grams of protein per 3 ounces.
Scallops: Very lean with high protein.
Crab: A low-fat protein source when steamed or boiled.
Mussels and Clams: Low in calories and fat, rich in protein and minerals.

Tuna Choices

Tuna is lean, but preparation matters.

Canned in Water: Lowest calorie option, under 100 calories per 3 ounces.
Fresh Yellowfin Tuna: Very lean, around 109 calories per 3.5 ounces.

Cooking Methods Matter

Even lean seafood can become high-calorie with unhealthy preparation.

Healthy Cooking Methods

These methods minimize added fat:

Steaming
Baking
Grilling
Poaching
Sautéing (with minimal healthy oil)

Unhealthy Cooking Methods to Avoid

Deep-Frying: Adds significant fat and calories.
Heavy Sauces: Can add hundreds of calories.

Healthy vs. High-Calorie Seafood Choices

Approximate values for a 3-ounce serving:


Seafood Type	Preparation Method	Calories (approx.)	Fat (approx.)	Impact on Diet
Cod	Baked/Steamed	70 kcal	<1 g	Excellent low-calorie choice
Shrimp	Steamed/Boiled	101 kcal	1.45 g	Great low-calorie protein source
Salmon	Baked	175 kcal	10.5 g	Higher in fat, but omega-3s are healthy
Clams	Battered and Fried	333 kcal	19.5 g	High-calorie, high-fat option
Catfish	Battered and Fried	195 kcal	11.3 g	Significantly higher calorie count

Nutritional Benefits for Weight Management

Lean seafood aids weight loss through:

High Protein: Increases satiety, reduces calorie intake, preserves muscle.
Healthy Fats (Omega-3s): Support brain, heart health, and fat-burning.
Nutrient Density: Provides essential vitamins and minerals for metabolism and immune function.

Conclusion

Numerous seafood options are not fattening and support weight management. Prioritize lean fish and shellfish like cod, shrimp, and crab, and prepare them using healthy methods like baking, grilling, steaming, or poaching to keep meals light and nutritious. Incorporating these options can improve appetite control and metabolism. For sustainable choices, consult the Marine Stewardship Council.

Frequently Asked Questions

The least fattening fish are typically very lean white fish like cod, haddock, flounder, and sole. A 3-ounce serving of baked cod has about 70 calories and under 1 gram of fat.

When prepared by steaming, boiling, or grilling, shrimp is not fattening. It is very low in calories and high in protein, making it an excellent choice for a weight loss diet. Avoid deep-frying, which adds significant calories.

Yes, eating fish can help with weight loss. It provides high-quality protein that increases satiety and helps you feel full longer. The healthy fats (omega-3s) in many types of fish also support metabolism.

Lean fish, like cod and tilapia, are lower in fat and calories. Fatty fish, such as salmon and mackerel, are higher in healthy omega-3 fats and calories, but these beneficial fats are not associated with unhealthy weight gain and can aid weight management by promoting fullness.

No, shellfish such as crab and lobster are very low in fat and calories when steamed, boiled, or grilled. They are excellent sources of lean protein.

The best cooking methods are those that don't add extra fat, such as baking, grilling, steaming, or poaching. These methods preserve the natural flavor and nutritional value of the seafood.

Canned tuna can be a very lean and convenient protein source. To keep it low in calories, choose tuna canned in water rather than oil and avoid heavy, mayonnaise-based preparations.