Which is easier to digest, salmon or tuna?

January 5, 2026 •

4 min read

Fish is widely considered one of the easiest animal proteins for the body to digest. But when comparing which is easier to digest, salmon or tuna, the primary differentiator comes down to their fat content and preparation, influencing how your digestive system processes each fish.

Quick Summary

Tuna is generally easier to digest than salmon due to its significantly lower fat content, making it a better option for those with sensitive digestive systems, though cooking method greatly impacts both.

Key Points

Tuna is Easier to Digest: Due to its lower fat content, tuna is generally quicker and easier for the body to break down, making it ideal for sensitive stomachs.
Salmon is Higher in Fat: The higher fat content in salmon, though rich in healthy omega-3s, requires more time for digestion.
Cooking Method Matters: Baking, grilling, or steaming either fish makes it easier to digest compared to frying, which adds extra fat.
Both are High in Protein: Both salmon and tuna are excellent sources of easily digestible, complete protein, with tuna having a slight edge in protein content per ounce.
Canned Options: Canned light tuna packed in water is an extremely lean and digestible option, whereas canned salmon, while still healthy, retains more fat.
Mercury Concerns: Smaller tuna varieties like skipjack or 'light' tuna have lower mercury levels than larger ones, while salmon is generally a very low-mercury option.
Individual Sensitivity: Ultimately, personal digestive sensitivity and health conditions, such as IBS, can influence which fish is better for you.

Tuna vs. Salmon: The Fat Content Difference

At its core, the main difference in digestibility between salmon and tuna lies in their fat content. Salmon is a fatty fish, while tuna is a much leaner fish. For example, a 3-ounce serving of wild sockeye salmon has around 6 grams of fat, whereas a similar serving of yellowfin tuna contains only about 1 gram of fat.

Digesting fat is a more complex and time-consuming process for the body than digesting protein or carbohydrates. The body needs to use bile and enzymes to break down fats, which slows the entire digestive process. This is why a fatty meal can feel heavier in your stomach for longer. Because salmon is higher in fat, it will naturally take longer for your body to fully digest compared to a leaner option like tuna. For people with sensitive stomachs, conditions like Irritable Bowel Syndrome (IBS), or those recovering from illness, the lower fat content of tuna can make it the preferable choice for avoiding digestive discomfort.

The Protein Factor

Both salmon and tuna are excellent sources of high-quality, complete protein, meaning they contain all nine essential amino acids. Protein is a key nutrient for muscle repair and overall body function. The protein in fish, unlike that in red meat, is made up of amino acids that are easily broken down by the body, contributing to its overall high digestibility. Interestingly, tuna is slightly higher in protein per ounce than salmon, providing about 25 grams versus salmon's 22 grams in a 3-ounce serving. However, this small difference in protein content has a less significant impact on digestion speed than the difference in fat content.

How Cooking Methods Impact Digestibility

The preparation of the fish plays a huge role in how easily it is digested, regardless of whether you choose salmon or tuna. Frying fish in oil or butter adds significant fat and can make it much harder on the digestive system. Here are some cooking methods that promote better digestion:

Steaming: Gentle, low-heat cooking that requires no added oil, preserving the fish's natural tenderness.
Baking: Using a small amount of healthy fat like olive oil, baking provides a simple, clean preparation that is easy on the stomach.
Grilling: Grilling allows fat to drip away and adds flavor without heavy oils, though care should be taken not to overcook it.
Poaching: Cooking fish in simmering liquid keeps it moist and tender, making it exceptionally easy to digest.

Fresh vs. Canned Fish

For many, the most common way to consume tuna is canned, often packed in water or oil. While both canned tuna and salmon are convenient protein sources, their digestibility can differ.

Canned Tuna: Light canned tuna packed in water is a very lean, low-fat protein option that is very easy to digest. Canned albacore is also a lean option, though slightly higher in mercury. The canning process itself softens the fish, making it easier to break down.
Canned Salmon: Canned salmon is still a fattier option than canned tuna, but it offers a boost of omega-3s. The presence of bones in some canned salmon can also add valuable calcium. For a sensitive stomach, canned tuna in water remains the safer bet.

Comparison Table: Salmon vs. Tuna for Digestion


Attribute	Tuna	Salmon
Fat Content	Very Lean (approx. 1g per 3 oz)	Fatty (approx. 6g per 3 oz)
Omega-3s	Lower amount, but still present	Much Higher, a key source
Protein	Slightly Higher per ounce	Slightly Lower per ounce
Digestibility	Generally easier and quicker due to lower fat	Slower due to higher fat content, but still easy overall
Best for Sensitive Gut	Yes, excellent option	Good, but a lean white fish or tuna is better
Cooking Methods	Any gentle method works well	Any gentle method works well

Conclusion: Which Fish is Right for You?

Both salmon and tuna are healthy, nutritious additions to your diet, and both are generally easy to digest compared to other animal proteins. For individuals seeking the easiest-to-digest option, especially those with sensitive digestive systems, tuna is the clear winner due to its very low fat content. However, this does not make salmon a difficult fish to digest, just a slower one. Salmon is an excellent source of anti-inflammatory omega-3s, which offer a different set of significant health benefits.

Ultimately, the best choice depends on your personal health goals. If you prioritize easy and quick digestion, particularly when dealing with stomach sensitivities, opt for lean, properly prepared tuna. If your focus is on maximizing omega-3 fatty acid intake for heart and brain health, salmon is the superior choice, and you can still ensure smooth digestion by using gentle cooking methods like baking or steaming. For a balanced approach, incorporating both into your diet can provide a full spectrum of benefits.

To learn more about the nutritional comparison between the two fish, you can explore resources like Healthline's detailed guide on tuna vs. salmon.

Frequently Asked Questions

Yes, canned light tuna, especially when packed in water, is very easy to digest because it is a low-fat and already softened protein source.

Fat is digested more slowly than protein. Higher-fat fish like salmon take longer to pass through the digestive system, whereas leaner fish like tuna are processed more quickly.

For a sensitive stomach, tuna is generally the better option because its lower fat content is less likely to cause discomfort or bloating during digestion.

Very lean white fish such as cod, haddock, or tilapia are often cited as the easiest fish to digest, followed closely by lean tuna.

Yes, both canned tuna and salmon retain much of the nutritional value of their fresh counterparts, including protein, vitamins, and minerals.

Yes, aside from tuna, other easily digestible fish include cod, haddock, flounder, and tilapia, all of which are typically lower in fat.

To improve digestibility, opt for gentle cooking methods that don't add fat, such as steaming, baking, or poaching. Avoid frying, which can make the fish heavier and harder to digest.