If older guys who already exercise eat a small handful of walnuts every day for six weeks, it might lower a marker of body-wide inflammation by almost a third compared to just exercising.

What we've found so far is that adding 15 grams of walnuts daily may lower CRP, a marker of body-wide inflammation, in trained elderly men who are already doing concurrent training. Our analysis of the available research suggests this effect could occur over six weeks. We looked at one key assertion based on 54.0 supporting studies, with no studies refuting the idea [1]. This means the evidence we’ve reviewed leans toward a reduction in CRP levels when older men who already exercise include a small handful of walnuts in their daily diet. The data indicates this change might happen within six weeks, and the drop in CRP could be nearly one-third compared to those who only train without eating walnuts [1]. It’s important to note that CRP is just one marker of inflammation in the body. We’re not saying walnuts directly reduce inflammation for everyone, or that this result will happen the same way in all people. Our current analysis only covers what has been studied so far—older men who are already physically active and following a specific training routine. There isn’t enough evidence yet to say how walnuts compare to other nuts, whether more is better, or if this works the same in women or less active older adults. Also, we don’t have long-term data beyond six weeks from what we’ve reviewed. The takeaway: If you're an older man who already works out, adding about 15 grams of walnuts—roughly a small handful—each day might help lower one marker of internal inflammation. It’s a simple change that fits easily into a daily routine, and the existing evidence points in a promising direction. But we’ll keep updating our analysis as more data comes in.