Gut and microbiome activity and metabolism depend on one’s diet, which can have long term health consequences. The following study presents how free living subjects’ metabolism responds to a daily consumption of 40 g of dark chocolate for up to 14 days. 30 people participated in a clinical test, which divided them into parties with low and high anxiety levels using validated psychological questionnaires. Biological fluids (urine and blood plasma) were collected during 3 test days at the beginning, midtime and at the end of a 2 week study. To study global changes in metabolism as a result of the chocolate consumption NMR and MS-based metabonomics were engaged. Those with higher anxiety showed a distinct metabolic profile which indicated a different energy homeostasis (lactate, citrate, succinate, trans-aconitate, urea, proline), hormonal metabolism (adrenaline, DOPA, 3-methoxy-tyrosine) and gut microbial activity (methylamines, p-cresol sulfate, hippurate). Dark chocolate reduced the urinary excretion of the stress hormone cortisol and catecholamines and normalized stress-related differences in energy metabolism (glycine, citrate, trans-aconitate, proline, β-alanine) and gut microbial activities (hippurate and p-cresol sulfate). The study provides strong evidence that a daily consumption of 40 g of dark chocolate during a period of 2 weeks is enough to change the metabolism of free living and healthy human subjects, as per variation of both host and gut microbial metabolism.

In order to see more detailed data and the results of the scientific research, consults the article “Metabolic Effects of Dark Chocolate Consumption on Energy, Gut Microbiota, and Stress-Related Metabolism in Free-Living Subjects” written by Francois-Pierre J. Martin, Serge Rezzi, Emma Pere-Trepat, Beate Kamlage, Sebastiano Collino, Edgar Leibold, Jurgen Kastler, Dietrich Rein, Laurent B. Fay, and Sunil Kochhar.