Fish vs chicken: which has more protein?

Fish vs chicken: which has more protein? Chicken breast wins on raw numbers. It offers about 31 g of protein per 100 g cooked. Most fish varieties provide 20–26 g per 100 g. But protein quantity is only part of the story. Factors like fat quality, how to increase protein without supplements, micronutrients, and digestibility also matter when choosing between the two.

Protein content: fish vs chicken per 100 g

The numbers differ based on the cut of chicken and the species of fish. Here is a quick comparison of cooked portions per 100 g.

• Chicken breast (skinless, cooked): approximately 31 g protein, 3.6 g fat, 165 calories
• Chicken thigh (skinless, cooked): approximately 25 g protein, 10 g fat, 209 calories
• Salmon (cooked, dry heat): approximately 22–25 g protein, 12–15 g fat, 206 calories
• Tilapia (cooked): approximately 26 g protein, 2.7 g fat, 128 calories
• Cod (cooked): approximately 22–23 g protein, 0.9 g fat, 105 calories
• Yellowfin tuna (cooked): approximately 29 g protein, 1 g fat, 130 calories

Chicken breast leads the protein count for most comparisons. However, some fish like yellowfin tuna come very close at around 29 g per 100 g cooked. Tilapia also matches or edges past chicken thigh in protein density.

If your primary goal is maximum protein per calorie, skinless chicken breast and cod are the two leanest options. For those looking at affordable protein sources on a budget, chicken breast generally costs less per gram of protein than most fresh fish.

Amino acid quality and digestibility

Both chicken and fish are complete proteins. This means they contain all nine essential amino acids the body cannot produce on its own. These amino acids are critical for muscle repair, enzyme production, and immune function.

The Protein Digestibility Corrected Amino Acid Score (PDCAAS) for both chicken and fish is close to 1.0, which is the maximum score. Eggs and whey protein score a perfect 1.0. Chicken, fish, and beef all score a solid 80–85 on the biological value scale for muscle building. In practical terms, the difference in protein quality between the two is negligible.

Both sources also contain high amounts of leucine, the amino acid most directly linked to triggering muscle protein synthesis. A typical 150 g serving of either chicken or fish provides roughly 2.5–3 g of leucine, which is the threshold needed to maximise the anabolic response in most adults.

Fish vs chicken for muscle building

For pure protein density, chicken breast is the go-to option used by bodybuilders and athletes for decades. Its high protein-to-calorie ratio makes it ideal during fat-loss or muscle-gain phases where every calorie counts.

Fish brings something chicken cannot: omega-3 fatty acids. Fatty fish like salmon and mackerel are rich in EPA and DHA. Research published in the American Journal of Clinical Nutrition found that omega-3 fatty acid supplementation increased the rate of muscle protein synthesis in older adults. EPA and DHA get incorporated into the muscle cell membranes and are linked to enhanced rates of muscle protein synthesis and reduced muscle protein breakdown.

This is especially relevant for adults over 40 who face age-related muscle loss. If you are concerned about preventing muscle loss after 40, including fatty fish 2–3 times per week alongside chicken could be a smart strategy.

For those training hard and tracking macros, the practical difference between 31 g (chicken) and 25 g (salmon) per 100 g is about one extra bite of chicken. At a full meal portion of 150–200 g, either source puts you in the 40–60 g protein range per serving.

Beyond protein: micronutrient differences

Protein alone does not define a food's value. Here is where fish and chicken differ meaningfully.

Fish advantages

• Omega-3 fatty acids (EPA and DHA): salmon has 30–50 times more omega-3s than chicken. These fats support heart health, reduce inflammation, and may aid recovery after intense exercise.
• Vitamin D: fatty fish is one of the few natural dietary sources of vitamin D, important for bone health and immune function.
• Iodine: important for thyroid function, fish is a significantly better source than chicken.
• Selenium: particularly high in tuna, selenium supports antioxidant defence.

Chicken advantages

• B vitamins: chicken is rich in niacin (B3) and pyridoxine (B6), both essential for energy metabolism.
• Zinc and iron: chicken provides roughly 5 times more zinc and 4 times more iron compared to salmon.
• Lower cost and higher versatility: chicken is generally cheaper and easier to cook in multiple preparations.

People who want to understand how complete proteins from meat compare to plant-based options will find that both chicken and fish outperform most individual plant sources in amino acid completeness.

Which is better for weight loss?

Both fish and chicken support weight loss effectively. They are high in protein and low in carbohydrates. Protein promotes satiety, helping you feel full for longer and reducing overall calorie intake.

Skinless chicken breast and lean white fish like cod or tilapia are the best options for calorie-controlled diets. Cod provides just 105 calories per 100 g. Chicken breast comes in at about 165 calories per 100 g.

Fatty fish like salmon has more calories due to its healthy fat content. However, this fat is beneficial. Studies suggest that fish and seafood, even when higher in fat, can support weight loss when included in an energy-restricted diet. For a deeper look at how protein aids fat loss, see this guide on how much protein you need for weight loss.

Mercury and safety concerns with fish

One concern with fish is mercury. Larger predatory fish at the top of the food chain tend to accumulate more mercury. High-mercury fish include swordfish, king mackerel, and bigeye tuna.

Lower-mercury options that are safe for regular consumption include salmon, sardines, cod, and tilapia. For most adults, eating 200 g of low-mercury fish daily is considered safe. Pregnant women should follow specific guidelines from bodies like the FDA and limit high-mercury varieties.

Chicken does not carry this concern, making it a simpler choice for people who prefer not to worry about contaminant levels.

Protein comparison table: popular fish and chicken cuts

This table summarises protein, fat, and calorie content per 100 g of cooked meat for quick reference.

• Chicken breast: 31 g protein, 3.6 g fat, 165 kcal
• Chicken thigh: 25 g protein, 10 g fat, 209 kcal
• Chicken drumstick: 24 g protein, 8 g fat, 172 kcal
• Salmon (Atlantic, farmed): 22 g protein, 15 g fat, 206 kcal
• Yellowfin tuna: 29 g protein, 1 g fat, 130 kcal
• Tilapia: 26 g protein, 2.7 g fat, 128 kcal
• Cod: 22 g protein, 0.9 g fat, 105 kcal
• Sardines (canned): 25 g protein, 11 g fat, 208 kcal

Values are approximate and may vary by cooking method and source. Data referenced from the USDA FoodData Central database.

How to choose between fish and chicken

The best approach for most people is rotation. Use chicken for its protein density and affordability. Use fish for its omega-3 content and micronutrient diversity. Here are some practical guidelines.

• Eat fish at least 2–3 times per week, focusing on oily fish like salmon or mackerel for omega-3 benefits.
• Use chicken breast as a daily protein staple if you are tracking calories closely.
• Choose lean white fish (cod, tilapia) on days when you want a lighter meal with fewer calories.
• Opt for canned tuna or sardines as budget-friendly, high-protein options that need no cooking.
• Vary your cooking methods. Grilling, baking, and poaching preserve nutrients better than deep frying.

If you are trying to hit a specific daily protein target, knowing how much protein comes from your other meals matters too. Pairing your chicken or fish with a nutritious dal and roti combination can help you reach your target without relying on supplements.

Common mistakes when comparing fish and chicken protein

• Ignoring the cut: chicken thigh has almost the same protein as most fish. The advantage of chicken only holds strongly for breast meat.
• Focusing only on grams of protein: the 5–7 g difference between chicken breast and salmon matters less than overall diet quality, consistency, and variety.
• Overlooking omega-3s: choosing chicken exclusively means missing out on EPA and DHA, which have documented benefits for heart health, brain function, and recovery from exercise.
• Assuming all fish is lean: salmon and mackerel are high-fat fish. They offer healthy fats but also more calories than white fish or chicken breast.
• Eating only one protein source: rotating between chicken, fish, eggs, and legumes provides a wider range of micronutrients.

Frequently asked questions

Is fish healthier than chicken?

Neither is universally healthier. Fish provides omega-3 fatty acids and vitamin D that chicken lacks. Chicken provides more zinc and iron. Both are excellent protein sources. The healthiest approach is to include both in your weekly diet.

Can fish replace chicken for muscle building?

Yes, for most people. The protein difference per serving is small. Fish also provides omega-3s that may support muscle protein synthesis and recovery. Athletes may benefit from using both rather than choosing one exclusively. Those interested in building muscle without supplements can explore strength training nutrition strategies using whole foods.

Which fish has the most protein?

Yellowfin tuna leads among common fish with about 29 g of protein per 100 g cooked. Tilapia follows at 26 g. Salmon and cod provide 22–25 g per 100 g.

How much chicken or fish should I eat daily for muscle building?

This depends on your total protein target. Most guidelines suggest 1.6–2.2 g of protein per kg of body weight for active individuals focused on muscle growth. A 70 kg person would need roughly 112–154 g of protein daily. That can be met with 200–300 g of chicken or fish per day, combined with other protein sources like eggs, dairy, and legumes.