Sandhu, A.K., I. Edirisinghe, B. Burton-Freeman, 2025. Pecans and human health: distinctive benefits of an American nut. Nutrients. 17, 3686. https://doi.org/10.3390/nu17233686
Pecans are a tree nut native to America with a rich content of unsaturated fatty acids, minerals, fiber, and a diverse array of bioactive components, including polyphenols, tocopherols, and phytosterols. This review summarizes variations in the phenolic composition of pecans from various parts of the world based on cultivar, maturity stage, postharvest storage, and processing. Additionally, the review delves into the bio-accessibility and bioavailability of bioactive components from pecans and their potential influence on diet quality, body weight, satiety, cardiometabolic, brain and gut health. Data from human clinical trials suggest that replacing foods/snacks with pecans improves overall diet quality and lipid profiles. However, inconsistent effects are observed on vascular function, glycemia, and inflammation. Body weight changes after pecan intake are reported as neutral, with promising results on satiety peptides and appetite regulation. Cognition and gut health are emerging areas of research with very limited data from both human and preclinical models, warranting further investigation. Overall, the current literature supports the cardiometabolic benefits of pecans within healthy dietary patterns. Future research should focus on well-controlled studies targeting at-risk populations to understand mechanistic endpoints such as metabolomics, microbiome, and vascular function assessments to substantiate the role of pecans in dietary guidance.
Park, J.M., K.B. Hahm, 2024. Dietary walnuts prevented indomethacin-induced gastric damage via AP-1 transcribed 15-PGDH, Nrf2-mediated HO-1, and n-3 PUFA-derived Resolvin E1. Int J Mol Sci. 25(13):7239. https://doi.org/10.3390/ijms25137239.
Non-steroidal anti-inflammatory drugs (NSAIDs), the most highly prescribed drugs in the world for the treatment of pain, inflammation, and fever, cause gastric mucosal damage, including ulcers, directly or indirectly, by which the development of GI-safer (-sparing) NSAIDs relates to unmet medical needs. This study aimed to document the preventive effects of walnut polyphenol extracts (WPEs) against NSAID-induced gastric damage along with the molecular mechanisms. RGM-1 gastric mucosal cells were administered with indomethacin, and the expressions of the inflammatory mediators between indomethacin alone or a combination with WPEs were compared. The expressions of the inflammatory mediators, including COX-1 and COX-2, prostaglandin E2, 15-hydroxyprostaglandin dehydrogenase (15-PGDH), and antioxidant capacity, were analyzed by Western blot analysis, RT-PCR, and ELISA, respectively. HO-1, Nrf-2, and keap1 were investigated. The in vivo animal models were followed with in vitro investigations. The NSAIDs increased the expression of COX-2 and decreased COX-1 and 15-PGDH, but the WPEs significantly attenuated the NSAID-induced COX-2 expression. Interestingly, the WPEs induced the expression of 15-PGDH. By using the deletion constructs of the 15-PGDH promoter, we found that c-Jun is the most essential determinant of the WPE-induced up-regulation of 15-PGDH expression. We confirmed that the knockdown of c-Jun abolished the ability of the WPEs to up-regulate the 15-PGDH expression. In addition, the WPEs significantly increased the HO-1 expression. The WPEs increased the nuclear translocation of Nrf2 by Keap-1 degradation, and silencing Nrf2 markedly reduced the WPE-induced HO-1 expression. We found that the WPE-induced HO-1 up-regulation was attenuated in the cells harboring the mutant Keap1, in which the cysteine 151 residue was replaced by serine. These in vitro findings were exactly validated in indomethacin-induced gastric rat models. Daily walnut intake can be a promising nutritional supplement providing potent anti-inflammatory, antioxidative, and mucosa-protective effects against NSAID-induced GI damage.
Key Area: Gut Health
Shi Y, Kan J, Wang W, Cao Y, Wu Y, Chen X, Zheng W, Yang F, Du J, He W, Zhu S., 2024. Nut consumption, gut microbiota, and body fat distribution: results of a large, community-based population study. Obesity (Silver Spring). 32(9):1778-1788.
Objective: We aimed to investigate the relationships among nut consumption, gut microbiota, and body fat distribution. Methods: We studied 2255 Chinese adults in the Lanxi Cohort living in urban areas in Lanxi City, China. Fat distribution was assessed by dual-energy x-ray absorptiometry, and nut consumption was assessed using food frequency questionnaires. 16S ribosomal RNA (rRNA) sequencing was performed on stool samples from 1724 participants. Linear regression and Spearman correlation were used in all analyses. A validation study was performed using 1274 participants in the Lanxi Cohort living in rural areas. Results: Nut consumption was beneficially associated with regional fat accumulation. Gut microbial analysis suggested that a high intake of nuts was associated with greater microbial α diversity. Six genera were found to be associated with nut consumption, and the abundance of genera Anaerobutyricum, Anaerotaenia, and Fusobacterium was significantly associated with fat distribution. Favorable relationships between α diversity and fat distribution were also observed. Similar relationships between gut microbiota and fat distribution were obtained in the validation analysis. Conclusions: We have shown that nut consumption is beneficially associated with body fat distribution and gut microbiota diversity and taxonomy. Furthermore, the microbial features related to high nut intake are associated with a favorable pattern of fat distribution.
Singar, S., S. Kadyan, C. Patoine, G. Park, B. Arjmandi, R. Nagpal, 2024. The effects of almond consumption on cardiovascular health and gut microbiome: A comprehensive review. Nutrients. 4, 16, 1964. https://doi.org/10.3390/nu16121964
The consumption of almonds has been associated with several health benefits, particularly concerning cardiovascular and intestinal health. In this comprehensive review, we compile and deliberate studies investigating the effects of almond consumption on cardiovascular disease (CVD) risk factors and gut health. Almonds are rich in monounsaturated fats, fiber, vitamins, minerals, and polyphenols, which contribute to their health-promoting properties. Regular intake of almonds has been shown to improve lipid profiles by reducing LDL cholesterol and enhancing HDL functionality. Additionally, almonds aid in glycemic control, blood pressure reduction, and chronic inflammation amelioration, which are critical for cardiovascular health. The antioxidant properties of almonds, primarily due to their high vitamin E content, help in reducing oxidative stress markers. Furthermore, almonds positively influence body composition by reducing body fat percentage and central adiposity and enhancing satiety, thus aiding in weight management. Herein, we also contemplate the emerging concept of the gut–heart axis, where almond consumption appears to modulate the gut microbiome, promoting the growth of beneficial bacteria and increasing short-chain fatty acid production, particularly butyrate. These effects collectively contribute to the anti-inflammatory and cardioprotective benefits of almonds. By encompassing these diverse aspects, we eventually provide a systematic and updated perspective on the multifaceted benefits of almond consumption for cardiovascular health and gut microbiome, corroborating their broader consideration in dietary guidelines and public health recommendations for CVD risk reduction.
