Fish protein, particularly from fatty fish such as salmon, mackerel, and sardines, has been scientifically investigated for its benefits in supporting heart health. Multiple studies indicate that diets rich in fish and fish protein are associated with lower risks of cardiovascular diseases (CVD), including heart failure and coronary artery disease. This effect is largely attributed to the high content of omega-3 polyunsaturated fatty acids (EPA and DHA) in fish, which are known to reduce inflammation, lower blood triglyceride levels, decrease blood pressure, and improve endothelial function. However, emerging research also points to beneficial effects of fish-derived peptides and proteins themselves, independent of omega-3s. These peptides may exhibit blood pressure-lowering (antihypertensive), cholesterol-lowering, and antioxidant properties, all of which contribute to cardiovascular health.

Systematic reviews and randomized controlled trials have shown modest but significant reductions in blood pressure and improved lipid profiles in individuals consuming fish protein compared to other animal proteins. The American Heart Association recommends regular fish consumption as part of a heart-healthy diet. While most of the benefit is attributed to the combined nutrient package of fish (protein plus omega-3s), there is enough scientific evidence to support the use of fish protein for supporting heart health, especially in the context of a balanced diet. Therefore, the evidence level is rated as 4 out of 5, reflecting strong, though not absolute, scientific support.