Salmon

Salmon

Salmon is one of the most studied and most eaten fish in the world, and one of the few food sources that simultaneously provide complete protein, long-chain omega-3 and vitamin D in significant amounts. That combination is rare: most protein sources do not provide omega-3, and most plant sources of omega-3 provide ALA, which the body converts to EPA and DHA at an efficiency of only a few percent.

How much protein is in salmon?

22-25 grams per 100 grams of cooked fish, depending on the variety and cooking method. A typical home fillet (150-180 grams) provides about 34-42 grams of protein — enough to cover a full protein serving for a meal.

It is a complete protein of high biological value, containing all nine essential amino acids, including enough leucine to stimulate muscle protein synthesis.

Nutrition facts per 100 grams (cooked Atlantic salmon)

Farmed versus wild salmon — the real difference

This is the most common question, and the answer is more complicated than “wild is always better”:

• Farmed salmon is fattier — about 12 grams of fat per 100 grams compared with 8 in wild. Because omega-3 sits in the fat, farmed salmon actually provides more EPA and DHA per serving, not less.
• Wild salmon is leaner and higher in protein, and provides 1.5-2 times the vitamin D.
• The omega-6 to omega-3 ratio is worse in farmed salmon, because of feed based on vegetable oils. Still, the absolute ratio remains favorable compared with almost any other protein source.
• Contaminants: older studies found higher levels of PCBs and dioxins in farmed salmon. Feed regulations that have changed since then have narrowed the gap significantly, and health authorities agree that the benefit of the omega-3 outweighs the risk in both types.
• Astaxanthin — the antioxidant pigment that gives salmon its color. In wild salmon it comes from krill and algae; in farmed salmon it is added to the feed. Chemically it is the same molecule.

The practical conclusion: both types are a good choice. Farmed salmon is cheap, available and provides more omega-3 per serving. Wild salmon is leaner, richer in vitamin D and more sustainable — but significantly more expensive.

Benefits

• Long-chain omega-3: EPA and DHA are the biologically active forms, unlike the plant ALA provided by flax seeds and walnuts, whose conversion in the body is only 5%-10%. One serving of salmon covers the weekly recommendation of 250-500 mg a day.
• Heart health: eating oily fish twice a week is consistently linked in large cohorts to lower cardiovascular mortality. The observed mechanisms: lowering triglycerides by 15%-30%, reducing inflammation, and stabilizing heart rhythm.
• Vitamin D: one of the few truly dietary sources. A 150-gram serving of wild salmon may provide over 1,000 IU — more than the recommended daily intake.
• DHA and brain health: DHA is a key structural component of nerve cell membranes and the retina. It is especially important in pregnancy and infancy for the development of the brain and vision.
• Selenium and B12 in significant amounts.
• Low mercury: about 0.02 ppm — among the lowest in fish, and 6-17 times less than tuna. Salmon is a short-lived fish that is not a predator at the top of the food chain, so it is considered safe even in pregnancy.

Downsides and considerations

• Price: one of the most expensive protein sources. Sardines and mackerel provide a similar amount of omega-3 at a fraction of the price.
• Smoked salmon — sodium and safety: 100 grams of cold-smoked salmon contain 600-1,200 mg of sodium. In addition, cold smoking does not cook the fish, so there is a risk of listeria — pregnant women should avoid cold-smoked salmon unless it has been thoroughly heated.
• Sustainability: intensive farming in sea cages causes local pollution, sea lice and fish escaping into the wild. Wild salmon stocks in the Atlantic Ocean are in poor condition. An ASC label for farming or MSC for wild fishing indicates better practices.
• Fish allergy: one of the major allergens, and reactions can be severe.
• Anisakiasis in raw fish: salmon sushi and sashimi may contain a parasitic worm. Commercial freezing at -20°C for a week (or -35°C for 15 hours) kills it — so don’t use “fresh” salmon from the counter for homemade sushi.
• Overcooking wastes the advantage: prolonged heating at high temperature oxidizes some of the omega-3. Gentle baking, steaming or brief grilling are better than long frying.

Practical use

• Frequency: twice a week, a 120-180 gram serving — this is the official recommendation of most health organizations for oily fish.
• Best preparation: bake at 160-180°C until an internal temperature of 50-52°C (medium). Above 60°C the fish dries out and the fat runs out.
• Don’t remove the skin: the layer of fat underneath it is especially rich in omega-3. Cooking skin side down preserves it.
• Canned salmon is a cheap and excellent alternative — especially the version with soft bones, which adds significant calcium.
• Cheaper alternatives of the same quality: sardines (1,400-1,500 mg of omega-3) and mackerel — both smaller, even lower in mercury and much cheaper.

Summary

Salmon provides 22-25 grams of protein per 100 grams, 1,200-2,300 mg of omega-3 and vitamin D in an amount almost no other food provides — with especially low mercury. The farmed versus wild question is less decisive than people think: farmed provides more omega-3 per serving, wild provides more protein and vitamin D. Two servings a week cover the recommendation, and if the price puts you off you will get a similar benefit from sardines at a third of the price.