Effect of sustainable food habits on gut microbiota diversity: A pilot study

Abstract Background To reach climate goals, sustainable food habits are needed and a plant-based diet is more climate-friendly. However, analyses of food products show that the highest levels of pesticide residues have been found in vegetables, fruits and cereal. Further, pesticide residues have been seen to decrease microbiota diversity. Since microbiota diversity is linked to human health, understanding these dynamics is crucial. This study aimed to evaluate the effect of sustainable food habits on gut microbiota diversity. Methods An 8-week intervention study on sustainable food habits with participants randomized into three groups and assigned to different diets; climate friendly (n = 8), organic (n = 9) and control group (n = 9). Data was collected at baseline, at 4 weeks, and at 8 weeks and included a comprehensive meal questionnaire (Meal-Q), urine samples for pesticide analysis, and fecal samples for gut microbiota diversity. As intervention the groups attended four educational sessions about their specific diet. Linear mixed-effects models were used for data analyses. Results There was no indication of adverse effects of a climate friendly diet (p = 0.79) or an organic diet (p = 0.32) on gut microbiota diversity compared to the control group. Pesticide residues that showed negative effects on gut microbiota diversity were mepiquat (p < 0.05) and chlormequat (p < 0.05). The single food items that had adverse effects on gut microbiota diversity was Lemonade (p < 0.05), Juice (p < 0.05), and Brie cheese (p < 0.05). Conclusions Despite its small sample size, this study provides valuable insights, supported by an 8-week longitudinal design and comprehensive monitoring of dietary habits. Notably, both climate-friendly and organic diets showed trends toward increased gut microbiota diversity over time. These findings need to be confirmed in future studies with longer durations and larger sample size. Key messages • A climate-friendly diet not only benefits planetary health but also holds potential for individual health improvements. • Increased intake of plant-based items did not reduce gut microbiota diversity.