Eating walnuts might help your blood vessels work better by improving blood flow, which could lower your risk of heart disease.

What we've found so far suggests that eating walnuts may be linked to better blood vessel function in adults. Our analysis of the available research shows the evidence leans toward a potential benefit for blood flow, which could play a role in heart health [1]. We reviewed 45.0 studies or assertions, all of which support the idea that walnuts might help blood vessels work more effectively [1]. These findings point to improvements in how blood moves through the body, a factor we know is important for cardiovascular health. However, we don’t have any studies in this analysis that refute the claim, so our view is one-sided at this stage. It’s important to note that while the evidence we’ve reviewed supports this idea, we’re not saying walnuts definitely improve blood vessel function. We’re only reporting what the current data shows. Also, we don’t know from this evidence how much or how often walnuts need to be eaten, or whether the effects are the same for everyone. Since our analysis is based on a one-sided body of evidence, we recognize this picture could change as more research becomes available. We’re not drawing conclusions—just sharing what we’ve found so far. Practical takeaway: Adding walnuts to your diet might help your blood vessels work better, but don’t count on them alone for heart health. They’re a food choice worth considering, not a guaranteed fix.