Adults suffering from Rheumatoid Arthritis (RA) tend to have less diverse diet, lower micronutrient adequacy and food habits that may promote inflammation compared to healthy individuals, said researchers at the ICMR-National Institute of Nutrition (ICMR-NIN) here in Hyderabad.
Rheumatoid arthritis is a long-term autoimmune disorder in which the body’s immune system mistakenly attacks healthy tissues, particularly the joints, leading to pain, swelling and reduced mobility. While genetic and environmental factors are known to contribute to the disease, the role of dietary patterns in the Indian population has not been extensively studied.
In this case-control study involving 615 adults aged 18 to 55 years from Hyderabad, including 301 newly diagnosed RA patients and 314 healthy individuals, researchers assessed participants’ food habits using a validated 131-item food frequency questionnaire.
The study examined three key indicators of diet quality: dietary inflammatory potential, measured using the Dietary Inflammatory Index (DII); dietary diversity, assessed through the Dietary Diversity Score (DDS); and micronutrient adequacy, evaluated using the Mean Probability of Adequacy (MPA).
The results revealed that participants with RA recorded a significantly higher median DII score of 2.18, compared to 0.37 among healthy controls, indicating that their diets had a greater inflammatory potential. Dietary diversity was also poorer among those with the disease.
Only 50.2% of RA patients had a high dietary diversity score, compared with 74.2% of healthy participants. Similarly, micronutrient adequacy was substantially lower in the RA group, with a median MPA of 18.9%, against 32.9% among controls.
Every one-unit increase in the Dietary Inflammatory Index was associated with a 17% increase in the odds of having RA after adjusting for age, sex and body mass index. In contrast, each one-unit increase in dietary diversity was linked to a 27% reduction in the odds of the disease, while every 10% increase in micronutrient adequacy was associated with a 12% lower likelihood of RA.
The findings point towards the importance of looking at overall dietary quality rather than individual nutrients in understanding chronic inflammatory conditions,” said study supervisor Devraj J. Parasannanavar. Dietary diversity and adequate intake of essential micronutrients are important components of a healthy diet and warrant further investigation in relation to inflammatory diseases, he added.
ICMR-NIN Director Bharati Kulkarni called for long-term and intervention-based studies to determine whether dietary improvements can help prevent or modify RA. Researchers also emphasized that though the study does not prove that poor diet causes RA, it highlights a significant association that merits further research, according to a press release. The study has been published in the international peer-reviewed journal – Nutrients.
