Plant-based diets are often promoted for everything from heart health to longevity, but new research suggests one potential benefit may involve inflammation.
A new systematic review and meta-analysis of randomized controlled trials found that plant-based dietary patterns were associated with lower levels of C-reactive protein, or CRP, a common blood marker linked to systemic inflammation.
The study, published in Nutrition, Metabolism and Cardiovascular Diseases, reviewed seven randomized controlled trials involving 541 participants. That makes it stronger than many observational nutrition studies, but it does not prove that plant-based eating directly prevents disease or that every plant-based diet is inherently healthier. Instead, it suggests that certain plant-forward eating patterns may help reduce one measurable sign of chronic low-grade inflammation.
Across the included trials, participants following vegan, vegetarian or whole-food plant-based diets had CRP levels that were about 1.13 mg/L lower on average than those following omnivorous diets.
That reduction may sound small, but CRP is commonly used as one indicator of inflammation and cardiovascular risk. Still, CRP is a surrogate marker, not a diagnosis. Lower CRP does not automatically mean someone will avoid heart disease, diabetes or cancer.
The findings also come with important caveats. Only seven studies met the researchers’ criteria, and “plant-based” did not mean exactly the same thing across all trials. Some diets likely emphasized whole grains, legumes, fruits and vegetables, while others may have differed substantially in food quality.
That distinction matters because plant-based does not automatically mean healthy. Highly processed foods can also be plant-based, while some omnivorous diets may still be rich in fiber and minimally processed foods.
Researchers believe the anti-inflammatory effects may partly stem from higher intakes of fiber, antioxidants and unsaturated fats, along with lower saturated fat intake. In other words, the benefit may be less about avoiding animal products alone and more about what foods are replacing them.
The review also found that programs combining plant-based eating with exercise often showed the greatest reductions, reinforcing a familiar but important point: overall lifestyle patterns may matter more than any single dietary label.
The authors reported that this research did not receive any specific grant funding from public, commercial or nonprofit organizations.