Study: Low-Calorie Diet May Increase PsA Risk

A low-calorie diet may increase the risk of developing psoriatic arthritis, according to findings from a Mendelian randomization (MR) study published in Clinical, Cosmetic and Investigational Dermatology.

The genetic analysis showed a statistically significant causal relationship between low-calorie diets and psoriatic arthritis (odds ratio [OR]: 1.05; 95% CI: 1.01 to 1.10; P = 0.008). No similar associations were found between low-calorie diets and other inflammatory skin diseases, including acne, atopic dermatitis, and psoriasis.

Researchers applied five MR methods—inverse variance weighted (IVW), MR-Egger, simple mode, weighted median, and weighted mode—to GWAS summary data. Sensitivity analyses, including MR-Egger regression and MR-PRESSO, were conducted to test for pleiotropy and validate the robustness of the results.

The study also found no evidence of a causal association between vegetarian or gluten-free diets and any of the skin conditions analyzed.

The use of Mendelian randomization allowed investigators to minimize confounding and reverse causality often found in observational studies. However, the authors acknowledged that the results are preliminary and warrant further exploration.

“This study offers preliminary insights into the links between diet and inflammatory skin conditions,” the authors wrote. “Future large-scale, multi-method research [is] needed to validate these findings and inform dietary recommendations.”¹