Proinflammatory Diets May Increase CRP and RA Onset Save

Despite the lack of good evidence, there has been great speculation about the role of diet in causing or alleviating inflammation. Now there's new research suggesting that proinflammatory diets can increase serum C-reactive protein (CRP) levels and also the risk of RA onset.

This study used a dietary survey called Dietary Inflammatory Index (DII) as a measure of dietary substances capable of augmenting inflammatory biomarkers. Diets with a high DII scores are associated with increased levels of CRP and interleukin-6. 

Patients in two large prospective registries, the European Prospective Investigation of Cancer (EPIC) and the Norfolk Arthritis Register (NOAR) were studied after linking databases.

The DII was calculated on healthy subjected being enrolled into EPIC between 1993 and 1998. Among the 25,522 EPIC patients they identified 159 who were subsequently diagnosed as RA from the NOAR registry. 

Comparison of highest and lowest quartiles of DII from EPIC enrollment revealed that high DII scores (proinflammatory diets) were associated with a higher risk of subsequent RA onset (DII: OR 1.90 [1.21-3.02]; p < 0.01).  However, when these analyses were adjusted for age, sex and BMI, the same level  significance was not achieved (OR 1.35 [0.85-2.19]; p = 0.2).

Diet may be one of the few modifiable factors that may influence inflammation and the risk of future RA onset.