(PTFS22-07-24) Individual and Combined Effects of Almond, Dark Chocolate, and Cocoa Consumption on the Stool Microbiota of Individuals With Overweight or Obesity

Objectives: Almonds containing unsaturated fats, fiber, and phytosterols and dark chocolate and cocoa containing flavanols have been shown to improve markers of cardiometabolic health and may alter the stool microbiota. To investigate the individual and combined effects of almonds, dark chocolate, and cocoa on the stool microbiota of adults with overweight or obesity.

Methods: A secondary analysis was conducted on samples from a published 4-period (4-wk/period) controlled-feeding crossover trial in adults with overweight or obesity. Participants (n=20, 9f/11m; 44.3 ± 9.4 y; 29.0 ± 2.5 kg/m²) consumed similar diets containing the following foods: 42.5 g of raw almonds (ALD, 253 kcal/d), 18 g of cocoa and 43 g of dark chocolate (CHOC, 251 kcal/d), both (ALD+CHOC, 504 kcal/d), or a control average American diet (AAD). Study foods replaced an isocaloric amount of butter, cheese, and refined grains in the AAD. Stool samples were collected at the beginning of the trial and the end of each diet period. Stool microbiota were measured using 16S sequencing. Community richness (α-diversity) was tested by amplicon sequence variant counts, Chao1 index, and Shannon index. Community dissimilarity (β-diversity) was assessed using the Bray-Curtis index. Bacterial relative abundance modulated by diet was tested with linear mixed models.

Results: Indices of α- and β-diversity were similar between diets. Lactococcus abundance was higher after AAD (mean ± SD, 0.13 ± 0.15%) compared to ALD (0.01 ± 0.02%, p=0.0014), CHOC (0.02 ± 0.02%, p=0.0017), and ALD+CHOC (0.01 ± 0.02%, p=0.0005). Faecalibacterium abundance was higher after ALD (8.5 ± 6.8%) vs. AAD (4.5 ± 3.9%, p=0.0077). Clostridium_III abundance was higher after ALD (0.41 ± 0.34%, p=0.027) and ALD+CHOC (0.42 ± 0.36%, p=0.014) compared to AAD (0.21 ± 0.28%). In addition, Clostridium_III abundance was higher after ALD (p=0.018) and ALD+CHOC (p=0.0076) compared to CHOC (0.19 ± 0.16%). Lachnobacterium abundance was higher after ALD+CHOC (0.35 ± 0.35%) vs. AAD (0.13 ± 0.15%, p=0.015) and CHOC (0.11 ± 0.07%, p=0.0074).

Conclusions: In those with overweight or obesity, replacing butter, cheese, and refined grains with almonds and/or dark chocolate and cocoa alters stool microbial composition. More research is needed to assess how microbial changes affect health.

Funding Sources: The Hershey Company and the Almond Board of California