You Cannot Take Dietary Supplements For Everything Like the Heart, Colon, Brain, and Skin – But One Fruit Can Fix That, According To Study
Acknowledging the widely accepted significance of nurturing a “healthy” gut microbiome for human well-being, extensive research has explored the potential influence of diet.
In a recent study, researchers from Western New England University and other institutions explored the potential of grapes to shape the human microbiome and consequently impact overall health.
The findings of the study were published in Nature’s Scientific Reports.
Multiple studies have consistently highlighted the significant role of diet in preserving and modulating the gut microbiome. The composition of an individual’s gut microbiome is influenced by the intake of various components such as fats, proteins, phytoestrogens, polyphenols, and carbohydrates.
This, in turn, affects the diversity of microbial species present. The population and abundance of gut microbes also impact the production levels of essential metabolites like acetate, butyrate, and propionate, which play vital roles in various physiological functions.
The annual grape production in the United States alone amounts to a staggering six million tons. Numerous studies have provided evidence that consuming grapes elicits a wide range of beneficial effects related to inflammation, gastrointestinal health, urinary bladder function, vision, atherosclerosis, and arteriosclerosis.
Moreover, studies conducted on mouse models have demonstrated that incorporating grapes into the diet significantly impacts gene expression, thereby influencing various liver and brain-related diseases.
Grapes are known to contain over 1,600 phytochemical compounds, which individually or in combination with others, exert effects on diverse physiological processes. Resveratrol, a widely studied chemical constituent found abundantly in grapes, stands out among them.
Previous research has shown that treating human intestinal microbiota with grape seed extracts leads to alterations in the profile of short-chain fatty acids (SCFAs) and relevant microbial populations. In mice fed a high-fat diet supplemented with grape powder, an increase in microbial populations responsible for butyrate synthesis was observed.
When grape powder was incorporated into a standard murine diet, the excretion of certain gut microbiota metabolites, including 5-hydroxyindole, gluconic acid, glyceric acid, myo-inositol, and 4-hydroxyphenylacetic acid, was attenuated. Conversely, an increase in metabolites such as scyllo-inositol, xylitol, 5-hydroxyindole, gluconic acid, 2′-deoxyribonic acid, and mannitol was observed.
In humans, consuming grapes has been associated with an increase in the alpha-diversity index of the gut microbiome. Additionally, grape consumption has been linked to reduced levels of total bile acids and cholesterol.
This two-month trial involved the recruitment of forty healthy individuals leading their normal daily lives. The participants underwent a specific protocol, starting with a two-week period of a restricted diet on Day 15. Following this, they transitioned to a two-week period of a restricted diet supplemented with the equivalent of three servings of grapes per day on Day 30. Finally, a one-month washout period concluded the trial on Day 60.
Throughout the grape consumption phase of the study, participants consumed approximately 2 1/4 cups of grapes daily.
Throughout the trial, plasma, urine, and fecal samples were collected from each participant for analysis. While initially, all forty participants were enrolled, only twenty-nine individuals successfully completed the trial, adhering to the entire study protocol.
The diversity and abundance of microbial populations in the gut, known as alpha-diversity, were analyzed in this study. Among male participants aged 24 to 44, no changes in alpha diversity were observed throughout the study period. However, female participants aged 29 to 39 exhibited a difference in alpha diversity on Day 60 compared to Day 15.
Beta diversity, which measures the variation between microbial communities, was analyzed using principal component analyses (PCA) and principal coordinate analyses (PCoA). Regardless of gender, no significant differences in beta diversity were found during the study period based on cluster analysis.
Common microbial species observed on Day 15, 30, and 60 included Faecalibacterium prausnitzii, Eubacterium rectale, Prevotella copri, Alistipes finegoldii, Fusicatenibacter saccharivorans, Bacteroides vulgatus, Alistipes putredinis, Bacteroides stercoris, Parabacteroides merdae, Bacteroides uniformis, Bifidobacterium adolescentis, Bacteroides coprocola, and Collinsella aerofaciens.
Microbial taxonomic analysis revealed significant microbial changes at each time point. On Day 30, there was an increased presence of Streptococcus thermophilus, which is considered a probiotic due to its production of lactic acid in the gut. Additionally, a decrease in Holdemania spp. was observed, which is consistent with microbial profiles observed in individuals following a vegetarian diet.
On Day 30, an increase in the abundance of Holdemania was noted, but no change in Streptococcus thermophilus occurred. On Day 60, a significant increase in organisms associated with the production of metabolites was observed, indicating a delayed gut microbial response to grape consumption since no microbial alterations were found on Day 15.
Grape consumption resulted in changes in certain enzyme levels. For instance, there was an increase in catechol 2,3-dioxygenase, which contributes to metabolic detoxification. Conversely, a decrease in (3S)-malyl-CoA thioesterase, influencing the glyoxylate cycle of microorganisms, was observed.
Compared to Day 15, significantly higher levels of error-prone DNA polymerase were observed on Days 30 and 60, suggesting a delayed effect of grape consumption on enzyme levels.
Compared to Day 15, elevated levels of cysteine peptidases and decreased levels of ABC transporters and Narl family were observed on Day 30. Additionally, compared to Day 30, an increase in oxidoreductases, ABC transporters, and Nonribosomal peptide synthetase (NRPS) was reported on Day 60.
“Our study showed that grapes actively impact the gut microbiome causing shifts in the intricate interactive networks and thus subtly changing the gut microbiome and the resulting chemicals it produces,” points out study author John M. Pezzuto.
The findings of the present study indicate that grape consumption does not disrupt the overall healthy state of the microbiome in participants. However, it does bring about changes in the taxonomic composition of the microbiome, KEGG pathways, enzyme levels, and metabolic profile.
“The data suggest health improvements in heart, colon, brain, skin, and more.”
“We now know that grapes can change the chemicals in the microbiome.”
“As these chemicals have access to all of our body organs it is logical to conclude that this leads to some of the health benefits that have now been established.”
Further research is required to determine whether these alterations have wider implications for overall health and well-being.
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