The recommendation to eat at least two portions of oily fish per week, one of which should be oily, comes from a substantial evidence base. Meta-analyses of prospective cohort studies consistently show that regular fish consumption is associated with a 16 to 20 percent reduction in cardiovascular mortality, a 17 percent reduction in coronary artery disease, and a 14 percent reduction in stroke. In populations with very high fish consumption such as Japan, the cardiovascular benefit appears even larger.
What Oily Fish Contains That Matters
Oily fish provides a unique combination of long-chain omega-3 fatty acids EPA and DHA that are not found in meaningful amounts in any plant food, alongside high-quality complete protein, vitamin D3, vitamin B12, selenium, and iodine. DHA is the primary structural fatty acid of neuronal cell membranes. EPA is the primary substrate for anti-inflammatory prostaglandins and lipoxins. The combination of these nutrients in a single food is unmatched by any supplement or fortified product.
Choosing the Right Fish
- Mackerel: one of the richest omega-3 sources and widely available; choose Atlantic or Pacific mackerel and eat the skin
- Sardines in olive oil: exceptional omega-3 content with bones that provide calcium; affordable and shelf-stable
- Wild salmon: higher omega-3 than farmed, though both are valuable; choose sockeye or coho for best quality
- Herring and kippers: traditional British oily fish with excellent omega-3 content
- Anchovies: used in small amounts in cooking they add omega-3 and umami without strong fishiness
- Avoid high-mercury fish including shark, swordfish, and marlin particularly for women who are pregnant or may become pregnant