Chronic inflammation is a major risk factor of cardiovascular disease progression in CKD, irrespective of confounding comorbidities. Based on current knowledge, microbially-derived metabolites such as short chain fatty acids (SCFA) play an important role in the regulation of chronic inflammatory processes in CKD patients. Children with CKD are known to have reduced serum levels of the SCFA propionic acid (PA), as a consequence of both gut microbial dysbiosis and reduced fiber intake. In animal and human studies the impact of PA on function and abundance of regulatory T cells (Treg) has been demonstrated. Consequently, the investigators aim to normalize the PA serum levels by oral PA food supplementation in hemodialysis patients in order to mitigate chronic inflammation.