Influence of a vegan diet on immunological parameters in connection with rheumatoid arthritis

It has long been known that diet is an important factor for normal immune function and health in general [1], [2]. In recent decades, the vegan diet (VE) has become popular in Western societies. Apart from the reported effects on body weight, cholesterol and blood pressure, VE is also considered to have anti-inflammatory effects [3], [4]. For example, VE has shown health-promoting effects in inflammation-related diseases such as coronary heart disease [5]. In several small controlled studies and case reports, VE improved symptoms in patients with rheumatoid arthritis (RA) and inflammation of the sacroiliac joint within a few weeks [6]-[11]. However, the underlying molecular mechanisms are largely unclear.

Our study aims to clarify whether and how immunological parameters associated with RA change when a vegan diet is followed. We also wanted to investigate whether there is a connection between the changes in the intestinal flora caused by a short-term change in diet and the patient's immune status.

To answer these questions, a controlled randomized study was conducted with 53 healthy volunteers aged 18-60 years. The subjects followed either a strictly vegan or meat-rich diet (after a normal mixed diet) for four weeks and were examined before the start and at the end of the intervention with regard to immune parameters relevant to RA. The study took place at the AZKIM Center Freiburg in collaboration with the AZKIM Centers in Heidelberg and Ulm.

publication about the study:

Lederer AK, Maul-Pavicic A, Hannibal L, Hettich M, Steinborn C, Gründemann C, Zimmermann-Klemd AM, Müller A, Sehnert B, Salzer U, Klein R, Voll RE, Samstag Y, Huber R (2020). Vegan diet reduces neutrophils, monocytes and platelets related to branched-chain amino acids – A randomized, controlled trial. Clin Nutr. 39(11):3241-3250. PubMed


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