SUBSTITUTING just one meat-based meal with a vegetarian or vegan alternative has been proven to reduce serum ammonia levels for up to 3 hours in patients with cirrhosis, according to a recent study. The research, led by Bryan Badal, Richmond VA Medical Center, Richmond, Virginia, USA, was conducted on patients who follow a Western meat-based diet, and could transform patient care in hepatology.
Previous studies have demonstrated the benefit of a complete diet change from meat-based to vegetarian in patients with cirrhosis, however this shift is hard to sustain. Badal and colleagues aimed to investigate whether a smaller change in diet would provide any benefit to patients with cirrhosis.
This randomised trial involved 30 men with cirrhosis who were on a stable, Western meat-based diet, 50% of whom had prior hepatic encephalopathy (HE). After fasting overnight, patients were assigned to 20 g of a meat (n = 10), vegan (n = 10), or vegetarian (n = 10) burger meal, eaten under observation. The team collected blood samples for analysis of metabolomics and ammonia at baseline and every hour for 3 hours following the meal. At baseline, mean ammonia levels for the three groups were 58.2 µmol/L, 36.1 µmol/L and 52.9 µmol/L, respectively, and stool microbiome composition was similar across groups.
Results showed that serum ammonia was “significantly elevated” in the meat group at 1 hour (75.1 µmol/L), 2 hours (76.4 µmol/L) and 3 hours (74.1 µmol/L) after meal consumption compared with the vegan (39.3 µmol/L, 41.2 µmol/L and 41.5 µmol/L) and vegetarian (50 µmol/L, 47.8 µmol/L and 45.5 µmol/L) groups.
“Even one meal change from meat-based to vegetarian or vegan can reduce ammonia generation that is independent of gut microbial change,” the team reported. “This was similar regardless of whether a patient had previously been diagnosed with HE.” They concluded that though patients should not restrict protein intake, switching one meat-based meal with a vegetarian or vegan option may improve serum ammonia levels in patients with cirrhosis, which could lead to significantly improved outcomes.
Victoria Antoniou, EMJ
Reference
Badal BD et al. Substitution of one meat-based meal with vegetarian and vegan alternatives generates lower ammonia and alters metabolites in cirrhosis: a randomized clinical trial. Clin Transl Gastroenterol. 2024;15(6):e1.
