Sardines vs Tuna: Which Is Richer in Omega-3 and Protein?

By Stayinghealthy !
Sardines and tuna comparison showing omega-3 fatty acids and protein content
Sardines contain significantly more omega-3, while tuna offers slightly higher protein per serving. / Freepik 


Sardines and tuna are among the most popular fish choices worldwide, praised for their high-quality protein and heart-healthy omega-3 fatty acids. But when it comes to nutrition, which one truly stands out? Below is an easy-to-follow, evidence-based comparison to help you decide which fish best fits your health goals.

Why Omega-3 and Protein Matter

Both sardines and tuna contain long-chain omega-3 fatty acids—especially DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid). These fats play a key role in supporting heart health, brain function, and reducing inflammation. Fish protein is also considered “complete,” meaning it provides all nine essential amino acids.

Basic Nutritional Comparison (Per 100 Grams)

Canned Sardines

  • Calories: 208
  • Protein: 24.6 g
  • Total Fat: 11.4 g
  • Omega-3 (EPA + DHA): 982 mg

Canned Light Tuna (in Oil)

  • Calories: 198
  • Protein: 29.1 g
  • Total Fat: 8.2 g
  • Omega-3 (EPA + DHA): 128 mg

Nutritional values can vary depending on fish species, preparation method, and whether the fish is packed in oil or water.

Which Fish Is Better for Omega-3?

While tuna does provide omega-3 fatty acids, sardines deliver a significantly higher amount. A 100-gram serving of sardines contains nearly eight times more omega-3 than the same portion of light canned tuna.

Health guidelines consistently emphasize marine omega-3s for their benefits, including:

  • Improving blood lipid levels
  • Reducing the risk of heart rhythm disorders
  • Supporting brain health and lowering inflammation

Which Fish Provides More Protein?

Tuna has a slight advantage in protein content, offering about 4–5 grams more protein per serving than sardines. Protein is essential for muscle maintenance, tissue repair, immune function, and overall metabolic health.

Both sardines and tuna are excellent sources of complete protein, making them ideal for balanced diets.

Mercury and Contamination Concerns

Mercury content is an important consideration when choosing fish. Sardines and light canned tuna are considered low-mercury options. However, some tuna varieties—such as albacore or yellowfin—may contain higher mercury levels and should be consumed in moderation.

Individuals who may need to limit fish intake due to mercury sensitivity include:

  • Pregnant or breastfeeding women
  • Children under 11 years old
  • Older adults or people with chronic health conditions

How to Choose the Best Option

No single fish can meet all nutritional needs. A varied diet that includes sardines, tuna, salmon, mackerel, and other nutrient-rich fish helps balance benefits while minimizing risks.

Choose Sardines If You Want:

  • Higher omega-3 fatty acid intake
  • Healthy fats with good-quality protein
  • Lower mercury exposure

Choose Tuna If You Prefer:

  • A milder flavor and greater versatility in recipes
  • A lean, low-fat protein source
  • Variety—some tuna types offer omega-3 levels similar to sardines