Effect of cashew nut (Anacardium occidentale L.) and its by-products (oil and soluble extract) on biomarkers of cardiometabolic risk and gut health
Authors:   , Meneguelli Talitha Silva 
Published: May 2024

Obesity is a global public health issue that triggers chronic low-level inflammation, and dysbiosis, which can lead to increased intestinal permeability. This contributes to various chronic conditions like liver fat accumulation, type 2 diabetes, and cardiovascular disease. Therefore, effective nutritional strategies to combat obesity, lower cardiovascular risk factors, and enhance gut health are essential. Cashew nut is one of the most consumed nuts and contain nutrients that can promote overall health. Thus, the objective of this dissertation was to evaluate the effects of cashew nut soluble extract (CNSE) in the microbiota, intestinal morphology and functionality, and inflammatory markers in an experimental model (Gallus gallus), and cashew nut and cashew nut oil consumption in weight, body composition, cardiometabolic and inflammatory markers, and intestinal permeability in humans. For the experimental study developed at Cornell University-USA, CNSE was assessed in vivo via intra- amniotic administration in intestinal brush border membrane (BBM) morphology, functionality, and gut microbiota. Four groups were evaluated: no injection (control); H2O injection (control); 10 mg/mL CNSE (1%); and 50 mg/mL CNSE (5%). The clinical trial developed at Universidade Federal de Viçosa - Brazil is an 8-wk randomized controlled three-arm dietary intervention, in which subjects were assigned to receive control (CT, free-nuts), cashew nut (CN, 30 g/day) or cashew nut oil (OL, 30 mL/day) plus an energy-restricted diet (-500 kcal). During initial and final days were measured anthropometry and body composition, collected blood, and performed the intestinal permeability test. Also, a 24-hour dietary recall was applied. Statistical analysis was conducted using SPSS (p- value <0.05). Related to experimental study, CNSE on duodenal morphological parameters showed, in both concentrations, higher Paneth cell numbers, goblet cell (GC) diameter in villi, and mixed GC per villi, while only in the 5% concentration showed higher GC diameter in crypt, depth crypt, and villi surface area. Further, both concentrations decreased GC number and acid and neutral GC. Also, treatment with CNSE at 5% showed a lower abundance of Bifidobacterium, Lactobacillus, and E. coli, which was statistically significant. Moreover, in intestinal functionality, CNSE upregulated aminopeptidase (AP) gene expression at 5% compared to 1% CNSE. In the intervention study, all three groups reduced body fat and weight, waist and hip circumferences. The CN- group had reduction in liver serum markers and in the number of individuals with obesity, as well as an improvement in the lipid profile intensified by the improvement in intestinal permeability, while OL-group had LDL-c, atherogenic index, and IL-1b reductions. Both intervention groups reduced neck circumference and apo B levels. However, it is important to highlight that there was no difference in adiposity, biochemicals, intestinal permeability and inflammatory markers between the three groups. In conclusion, cashew nut and cashew nut oil associated with weight loss and CNSE demonstrated beneficial potential for health. However, the hypothesis of the intervention study was denied since when comparing the three groups there was no statistically significant difference in the markers evaluated. Keywords: cashew nut; Anacardium occidentale L; clinical trial; obesity; cardiometabolic markers; intestinal permeability; inflammatory markers; experimental model; gut health.