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Cited by 1,638Gut microbiota and healthNutritional Studies and DietNutrition, Genetics, and Disease

High-level adherence to a Mediterranean diet beneficially impacts the gut microbiota and associated metabolome

Open access
De Filippis, Francesca, Pellegrini, Nicoletta, Vannini, Lucia, Jeffery, Ian B, La Storia, Antonietta, Laghi, Luca, Serrazanetti, Diana I, Di Cagno, Raffaella +9 more·2016·Gut
DOI 10.1136/gutjnl-2015-309957
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Abstract

Objectives Habitual diet plays a major role in shaping the composition of the gut microbiota, and also determines the repertoire of microbial metabolites that can influence the host. The typical Western diet corresponds to that of an omnivore; however, the Mediterranean diet (MD), common in the Western Mediterranean culture, is to date a nutritionally recommended dietary pattern that includes high-level consumption of cereals, fruit, vegetables and legumes. To investigate the potential benefits of the MD in this cross-sectional survey, we assessed the gut microbiota and metabolome in a cohort of Italian individuals in relation to their habitual diets. Design and results We retrieved daily dietary information and assessed gut microbiota and metabolome in 153 individuals habitually following omnivore, vegetarian or vegan diets. The majority of vegan and vegetarian subjects and 30% of omnivore subjects had a high adherence to the MD. We were able to stratify individuals according to both diet type and adherence to the MD on the basis of their dietary patterns and associated microbiota. We detected significant associations between consumption of vegetable-based diets and increased levels of faecal short-chain fatty acids, Prevotella and some fibre-degrading Firmicutes, whose role in human gut warrants further research. Conversely, we detected higher urinary trimethylamine oxide levels in individuals with lower adherence to the MD. Conclusions High-level consumption of plant foodstuffs consistent with an MD is associated with beneficial microbiome-related metabolomic profiles in subjects ostensibly consuming a Western diet. Trial registration number This study was registered at clinical trials.gov as NCT02118857.

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Crossref · 10.1136/gutjnl-2015-309957

Cites

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Nothing to recompute.

Claims the paper makes

0 of 41 cited sources checked · 0 supported · 0 flagged

  • Findingown data

    TMAO concentrations in urine were significantly lower among vegetarians and vegans (p<0.0001) than among omnivores.

    “Urinary TMAO levels were significantly lower in vegetarian and vegan ( p<0.0001) compared with O subjects (see online supplementary figure S6A).”
    Quote in the paperSubstantial claim
  • Findingown data

    Healthy Food Diversity index values correlated with Mediterranean diet adherence (Spearman's r=0.61, p<0.00001).

    “Moreover, the HFD index 34 values correlated with the adherence to the MD (Spearman's r=0.61, p<0.00001)”
    Quote in the paperNot a substantial claim
  • Findingown data

    Associations between Lachnospira and esters of butanoic and acetic acids were significant (p<0.05).

    “The associations between Lachnospira and esters of butanoic and acetic acids were significant ( p<0.05).”
    Quote in the paperNot a substantial claim
  • Findingown data

    Consumption of vegetable-based diets is associated with increased Prevotella and some fibre-degrading Firmicutes.

    “We detected significant associations between consumption of vegetable-based diets and increased levels of faecal short-chain fatty acids, Prevotella and some fibredegrading Firmicutes, whose role in human gut warrants further research.”
    Quote in the paperSubstantial claim
  • Findingown data

    L-Ruminococcus was positively associated with omnivore diets.

    “On the contrary, L-Ruminococcus (Ruminococcus genus assigned to Lachnospiraceae family) was positively associated to omnivore diets (see online supplementary table S2).”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim. 22
  • May combine two claims. 30

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingown data

    The first CIA component accounted for 50.7% of the variance and the second for 11.7%.

    “The first component of the CIA (horizontal) accounted for 50.7% of the variance, and the second component (vertical) accounted for another 11.7%.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    A small cluster of genera was associated with the vegetable-based diet, with the strongest correlations for Roseburia, Lachnospira and Prevotella; the last two also had a significant negative association with the omnivore diet (p<0.01).

    “A small cluster of genera was associated with the vegetablebased diet, with the strongest correlations found for Roseburia, Lachnospira and Prevotella, the last two also displaying a significant negative association with the omnivore diet ( p<0.01, see online supplementary table S2).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Healthy Food Diversity index values were significantly higher in vegetarian and vegan subjects, and in subjects with medium and high Mediterranean diet adherence (p<0.0001).

    “and were significantly higher in vegetarian and vegan subjects, as well as in subjects with medium and high adherence to the MD ( p<0.0001) (see online supplementary figure S1).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingown data

    Family-level microbiota composition showed an increase in Prevotellaceae abundance with plant-based diets, although this was not statistically significant after correction for multiple comparisons.

    “Pie charts of family level microbiota composition showed an increase in Prevotellaceae abundance with plant-based diets, although not statistically significant after correction for multiple comparisons (see online supplementary figure S3A).”
    Quote in the paperNot a substantial claim

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    Findingown data

    A larger cluster correlated positively with nutrients of animal origin and negatively with vegetable-based diet patterns.

    “A larger cluster correlated positively with the nutrients of animal origin and negatively with the vegetable-based diet patterns (figure 3).”
    Quote in the paperNot a substantial claim

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    Findingown data

    There was a very clear relationship between faecal SCFA profile and nutrient intake, with nutrient intake splitting into two distinct groups.

    “There was a very clear relationship between faecal SCFA profile and nutrient intake, with the latter variable also splitting into two distinct groups (figure 4A).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    Lachnospira and Prevotella were significantly linked to the highest and medium quartiles of Healthy Food Diversity values, respectively, and both were associated with plant-based diets.

    “Lachnospira and Prevotella were significantly linked to highest and medium quartiles of HFD values, respectively, and they were both associated to plant-based diets.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Three major clusters of genera and three clusters of nutritional information were detected.

    “Three major clusters of genera and three clusters of nutritional information were detected.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    In this Italian cohort, 88% of vegans, 65% of vegetarians, and 30% of omnivores had high adherence to the Mediterranean diet.

    “The majority of vegan and vegetarian subjects and 30% of omnivore subjects had a high adherence to the MD.”
    • Also stated in: § RESULTS · plain
      “Only 11% of the subjects (14 omnivores and 3 vegetarians) had low adherence to the MD, while 88% of the vegans, 65% of the vegetarians and also 30% of the omnivores showed high MD adherence rates.”
    • Also stated in: § DISCUSSION · plain
      “Remarkably, this latter category included about one-third of the omnivores.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Findingown data

    Analysis of Mediterranean diet adherence divided subjects into low, medium and high adherence groups.

    “Analysis of the adherence level to the MD 33 divided the subjects in three groups with low, medium and high adherence to MD (figure 1B).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Correlation analysis detected an influence of diet on microbiota structure, although not strong in absolute values.

    “Plotting the correlation between genera and dietary information, an influence of the diet on the structure of the microbiota could be detected, although not strong in terms of absolute values (figure 3).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    The first cluster included foods and nutrients typical of omnivore diets, while the third cluster included those mainly associated with vegetarian or vegan diets.

    “The first group included foods and nutrients typical of the omnivore diets while the third group included those mainly associated with vegetarian or vegan diets.”
    Quote in the paperNot a substantial claim

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    Findingown data

    Microbiota alpha diversity did not differ significantly between the three diet types or between different levels of Mediterranean diet adherence.

    “The microbiota alpha diversity values were not significantly different between subjects of the three diet types or between subjects showing different levels of adherence to the MD (data not shown).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    Subjects with high compliance to the Mediterranean diet showed enrichment in the same pathways, as well as pentose and glucuronate interconversions (ko00040), and propanoate (ko00640) and butanoate metabolism (ko00650) (p<0.05).

    “Interestingly, subjects with high compliance to MD showed enrichment in the same pathways, as well as those for pentose and glucuronate interconversions (ko00040), and propanoate (ko00640) and butanoate metabolism (ko00650) ( p<0.05).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Although the overall structure of the microbiota was similar across different diet types, gradients were detected with subjects stratifying on the basis of diet and microbiota.

    “In addition, although we noted that the overall structure of the microbiota was similar in subjects across the different diet types, gradients were detected with subjects stratifying on the basis of diet and microbiota.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Almost 90% of the subjects recruited showed at least medium adherence while 60% showed high-level adherence to the Mediterranean diet.

    “Almost 90% of the subjects recruited in this study showed at least medium adherence while 60% showed high-level adherence to the MD.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Despite the within-group variability, significant differences were found between the diet groups.

    “In spite of such variability, significant differences were found between diet groups”
    Quote in the paperSubstantial claim

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    Findingreasoning

    Vegan and vegetarian diets, which involve greater fibre intake from fruit and vegetables, were associated with higher short-chain fatty acid production, whereas an animal-based diet supported much lower levels.

    “Based on greater intake levels of fibre through fruit and vegetables, vegan and vegetarian diets were associated with higher production levels of SCFA, whereas the animal-based diet supported much lower levels.”
    Quote in the paperNot a substantial claim

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    Findingcitation

    Higher adherence levels to the Mediterranean diet were found here than in a larger Italian cohort study and in the multicentre prospective cohort study on dietary habits of 10 European countries.

    “Higher adherence levels to the MD were found here than in a larger Italian cohort study 33 and also in the multicentre prospective cohort study on the dietary habits of 10 European countries.46”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [33] Agnoli, 2011, A priori–defined dietary patterns are associated with reduced risk of stroke in a large Italian cohort, J Nutr source

      Not checked in the free run.

    • cites [46] Couto, 2011, Mediterranean dietary pattern and cancer risk in the EPIC cohort, Br J Cancer source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingcitation

    Higher median intake of fibre and starch was recorded in both omnivore and vegan subjects compared with the US cohort.

    “Interestingly, we recorded higher median intake of fibre and starch in both omnivore and vegan subjects compared with the US cohort.7”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [7] Wu, 2016, Comparative metabolomics in vegans and omnivores reveal constraints on diet-dependent gut microbiota metabolite production, Gut source

      Not checked in the free run.

  • May combine two claims.

    Findingown data

    With a larger cohort of 153 individuals that also included vegetarians, and with remarkable adherence to the Mediterranean diet, the study was able to detect significant associations between intake of fibre and vegetable foods and faecal SCFA concentrations.

    “With a larger cohort of 153 individuals that also included vegetarians, and with a remarkable adherence to the MD, we were able to detect significant associations between intake of fibre and vegetable foods and faecal SCFA concentrations.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Consumption of fibre, fruit and vegetables is associated with greater microbial richness at taxonomic or gene level.

    “In addition, several studies have shown an association between consumption of fibre, fruit and vegetables and increased microbial richness, at either taxonomic or gene level.[12][13][14]”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [12] Claesson, 2012, Gut microbiota composition correlates with diet and health in the elderly, Nature source

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    Premisecitation

    A few self-reported vegetarians had a non-significantly higher abundance of Prevotella than Bacteroides.

    “In addition, a few self-reported vegetarians had a non-significantly higher abundance of Prevotella compared with Bacteroides.11”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [11] Wu, 2011, Linking long-term dietary patterns with gut microbial enterotypes, Science source

      Not checked in the free run.

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    Premisecitation

    Habitual diet is a major determinant of gut microbiota composition and of the microbial metabolites that can affect the host.

    “Habitual diet plays a major role in shaping the composition of the gut microbiota, and also determines the repertoire of microbial metabolites that can influence the host.”
    • Also stated in: § INTRODUCTION · boosted
      “The role of diet in shaping the gut microbiota is widely recognised, and several recent reviews provide a comprehensive treatment of the subject.[1][2][3][4][5][6]”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [1] Jeffery, 2013, Diet-microbiota interactions and their implications for healthy living, Nutrients source

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  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    The Mediterranean diet is a pronounced but not exclusively vegetarian-oriented dietary pattern that has been shown to benefit obesity, type 2 diabetes, inflammatory diseases and cardiovascular diseases.

    “The MD is a pronounced, but not exclusively vegetarian-oriented dietary style, which has been demonstrated to be beneficial for the treatment of obesity, type 2 diabetes, inflammatory diseases and cardiovascular diseases.[26][27][28][29][30]”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [26] Salas-Salvadó, 2011, Reduction in the incidence of type 2 diabetes with the Mediterranean diet results of the PREDIMED-Reus nutrition intervention randomized trial, Diabetes Care source

      Not checked in the free run.

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    Premisecitation

    Vegetarian and vegan diets have well-described health benefits.

    “Vegetarian and vegan diets confer well-described health benefits. 23 24”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites 23 24

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    Premisecitation

    Residence in industrialised countries and consumption of Western diets, mainly omnivore-type, apparently lead to a gut microbiota composition more associated with disease.

    “Conversely, residence in industrialised countries and consumption of Western diets, which are mainly omnivore-type diets, apparently lead to a composition of the microbiota that is more associated with different types of disease.3”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [3] Albenberg, 2014, Diet and the intestinal microbiome: associations, functions, and implications for health and disease, Gastroenterol source

      Not checked in the free run.

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    Premisecitation

    Until recently, few studies had broadly and systematically examined the link between habitual diet and gut microbiota.

    “However, until recently, not many studies have broadly and systematically considered the association between habitual diet and gut microbiota. 2 7”
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    • cites 2 7

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    Premisecitation

    Differences in food access between populations can produce significant differences in gut microbiota taxonomic composition, separating agrarian and Western diets.

    “Some populations eat differently because they have different access to foods, and this can determine significant differences in the taxonomic composition of their gut microbiota, distinguishing agrarian and Western diets.[8][9][10]”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [8] De Filippo, 2010, Impact of diet in shaping gut microbiota revealed by a comparative study in children from Europe and rural Africa, Proc Natl Acad Sci USA source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Some enterogradients are generally agreed to be associated with vegetable-rich diets (Prevotella) or protein/fat-rich diets (Bacteroides/Clostridia).

    “Although there is a general agreement on the association of some enterogradients 18 with vegetable-rich (Prevotella) or protein/fat-rich diets (Bacteroides/Clostridia), 11 15 19-22”
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    • cites 11 15 19-22

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    Premisecitation

    Most studies and reviews of gut microbiota in relation to diet report increased Prevotella levels in response to an agrarian diet or fibre administration.

    “Most of the studies and reviews of gut microbiota in relation to diet report an increased level of Prevotella in response to consumption of an agrarian diet or on fibre administration.2-4 8 10 11 64”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites 2-4 8 10 11 64

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  • May combine two claims.

    Interpretationown data

    The remarkable adherence to the Mediterranean diet in the subjects studied, together with the remarkable link with Healthy Food Diversity, make the cohort a good model for a population following a healthy Western diet.

    “The remarkable adherence to the MD in the subjects studied here, together with the remarkable link we identified with HFD, make the cohort a good model for a population following a healthy Western diet.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Ruminococcus torques was recently found at increased levels in mice consuming a high fat and sugar diet and in association with susceptibility to Crohn's disease.

    “Consistently, Ruminococcus torques (Lachnospiraceae) was recently found at increased levels in mice consuming a high fat and sugar diet and with susceptibility to Crohn's disease.66”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [66] Martinez-Medina, 2014, Western diet induces dysbiosis with increased E coli in CEABAC10 mice, alters host barrier function favouring AIEC colonisation, Gut source

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    Premisecitation

    Higher short-chain fatty acid levels have been found in native Africans on an agrarian diet compared with African-Americans.

    “higher SCFA levels were found in native Africans on agrarian diet compared with African-Americans.22 54”
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    • cites 22 54

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    Premisecitation

    Decreased Lachnospira abundance has been reported in the gut microbiota of subjects with cholesterol gallstones and in the rectal mucosa of patients with HIV.

    “Decrease in Lachnospira abundance was recently highlighted in the gut microbiota of subjects with cholesterol gallstones 62 as well as in the rectal mucosa of patients with HIV, 63”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [62] Wu, 2013, Gut microbiota dysbiosis and bacterial community assembly associated with cholesterol gallstones in large-scale study, BMC Genomics source

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    • cites [63] McHardy, 2013, HIV infection is associated with compositional and functional shifts in the rectal mucosal microbiota, Microbiome source

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  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Wu et al reported negligible differences in faecal microbiota composition and plasma SCFA profiles in 15 vegan and 16 omnivore subjects, and found no evidence for diet-driven separations in either measure.

    “Wu et al 7 recently reported negligible differences in the faecal microbiota composition and plasma SCFA profiles in 15 vegan and 16 omnivore subjects, and found no evidence for dietdriven separations in either measure.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [7] Wu, 2016, Comparative metabolomics in vegans and omnivores reveal constraints on diet-dependent gut microbiota metabolite production, Gut source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Lachnospira is one of the core genera of the gut microbiota and is recognised as the only Firmicutes besides Faecalibacterium and Eubacterium able to degrade pectins.

    “Lachnospira is one of the core genera of the gut microbiota 4 and recognised as the only Firmicutes able to degrade pectins beyond Faecalibacterium and Eubacterium.56”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [4] Power, 2014, Intestinal microbiota, diet and health, Br J Nutr source

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    • cites [56] Fernandes, 2014, Adiposity, gut microbiota and faecal short chain fatty acids are linked in adult humans, Nutr Diabetes source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Short-chain fatty acids are produced by the gut microbiota when undigested polysaccharides are fermented.

    “SCFA are produced by the intestinal microbiota during fermentation of undigested polysaccharides.48”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [48] Tan, 2014, The role of short chain fatty acids in health and disease, Adv Immunol source

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  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Besides diet, several factors such as gender or age can affect the human metabolome.

    “Moreover, besides the diet, multiple factors can affect human metabolome, such as gender or age.[56][57][58]”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [56][57][58]

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  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Some Bacteroidetes, such as Alistipes, have already been reported to increase with elevated consumption of animal foods.

    “Some of the Bacteroidetes, such as Alistipes, have been already reported as increasing as a function of elevated consumption of animal foods, 12 15”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites 12 15

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    Premisecitation

    A reduced excretion of faecal phenols was observed after a 3-week high-resistant starch diet, and lower production of p-cresol sulfate and indoxyl sulfate was found in vegetarians.

    “Accordingly, a reduced excretion of faecal phenols was observed following a 3-week high-resistant starch diet, 59 while a significantly lower production of p-cresol sulfate and indoxyl sulfate were found in vegetarians.60”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [59] Birkett, 1996, Resistant starch lowers fecal concentrations of ammonia and phenols in humans, Eur J Clin Nutr

      Not checked in the free run.

    • cites [60] Patel, 2012, The production of p-cresol sulfate and indoxyl sulfate in vegetarians versus omnivores, Clin J Am Soc Nephrol source

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  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Acetate, propionate and butyrate have a well-documented protective role against several types of disease.

    “The protective role of acetate, propionate and butyrate against different types of disease is well documented.[49][50][51][52]”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [49][50][51][52]

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  • Classified as probably not a substantial claim.

    Premisecitation

    TMAO is linked to the risk of atherosclerosis and cardiovascular disorders.

    “TMAO is linked to risk of atherosclerosis and cardiovascular disorders.67 68”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites 67 68

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  • May combine two claims.

    Interpretationreasoning

    Healthy diets can beneficially modulate host-microbe interactions and establish effective pathways to prevent disease.

    “Healthy diets can, therefore, contribute to beneficially modulate host-microbe interactions and to establish effective pathways to prevent disease.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Eggs, beef, pork and fish are the major sources of carnitine and choline, which the gut microbiota convert to trimethylamine, which is then oxidised in the liver and released into the circulation as TMAO.

    “Eggs, beef, pork and fish are the major sources of carnitine and choline that are converted by the gut microbiota to trimethylamine, then oxidised in the liver and released into circulation as TMAO.69 70”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites 69 70

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  • May combine two claims.

    Interpretationown data

    The study provides tangible evidence that a healthy diet and a Mediterranean dietary pattern affect the gut microbiota and beneficially regulate microbial metabolism towards health maintenance in the host.

    “we provide here tangible evidence for the impact of a healthy diet and a Mediterranean dietary pattern on gut microbiota and on the beneficial regulation of microbial metabolism towards health maintenance in the host.”
    Quote in the paperSubstantial claim
46 of 46

  • The paper relies on this without support.

    Little is known about the structure of the gut microbiota in individuals with defined dietary habits such as strict vegans or vegetarians compared with omnivores.

    “little is known about the structure of the gut microbiota in individuals with defined dietary habits such as strict vegans or vegetarians compared with omnivores.”

  • The paper relies on this without support.

    Urinary trimethylamine oxide is a risk factor for cardiovascular disease.

    “a potential risk factor for cardiovascular disease.”
2 of 2

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • The positive impacts of a Mediterranean diet are mediated by its anti-inflammatory potential and are associated with changes in gut microbiota, including increase in Bacteroides and Clostridium phyla and reduction in Proteobacteria and Firmicutes phyla.

    “The positive impacts of a Mediterranean diet are mediated by its anti-inflammatory potential but is also associated with marked changes at the level of the gut microbiota, resulting in an increase in the abundance of Bacteroides and Clostridium phyla, and a reduction in Proteobacteria and Firmicutes phyla (Marlow et al., 2013) and associated metabolome (De Filippis et al., 2016).”

    From The Microbiota-Gut-Brain Axis (2019) · cites this paper as De Filippis et al., 2016

  • Animal fat and protein predominant diets have been clearly associated with specific changes in gut microbial composition when compared to plant-based diets.

    “For example, minimal differences have been shown between omnivores and vegetarians [35] although in some intervention studies, animal fat and protein predominant diets have been clearly associated with specific changes in gut microbial composition when compared to plant-based diets [67].”

    From Effect of Diet on the Gut Microbiota: Rethinking Intervention Duration (2019) · cites this paper as [67]

  • An observational study reported reduced urinary TMAO levels in subjects following a Mediterranean diet, and a trend toward lower urinary TMAO with greater reported adherence to the Mediterranean diet.

    “Reduced urine TMAO levels were recently reported in an observational study among subjects following a Mediterranean diet in a post hoc cross-sectional analysis comparing omnivores vs. vegetarians or vegans 35 ; moreover, a trend towards reduced urinary TMAO levels was observed among subjects with increased reported compliance with the Mediterranean diet (based on the PREDIMED trial compliance tool”

    From Impact of chronic dietary red meat, white meat, or non-meat protein on trimethylamine N-oxide metabolism and renal excretion in healthy men and women (2019) · cites this paper as [35]

  • Poor adherence to the Mediterranean diet is associated with increased l-Ruminococcus and Streptococcus bacteria, and higher urinary TMAO concentration.

    “In contrast, a poor adherence to the Mediterranean diet was associated with increased l-Ruminococcus and Streptococcus bacteria, and higher urinary TMAO concentration (96).”

    From Health Benefits of the Mediterranean Diet: Metabolic and Molecular Mechanisms (2018) · cites this paper as [96]

  • High adherence to a Mediterranean dietary pattern characterized by a high intake of vegetables, legumes, and fruit is associated with an enrichment of Firmicutes and Bacteroidetes and a rise in fecal short-chain fatty acid levels.

    “In another study, a high adherence to the Mediterranean dietary pattern characterized by a high intake of vegetables, legumes, and fruit was associates with an enrichment of Firmicutes and Bacteroidetes and a rise in fecal short-chain fatty acid levels.”

    From Health Benefits of the Mediterranean Diet: Metabolic and Molecular Mechanisms (2018) · cites this paper as [96]

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Authors
De Filippis, F., Pellegrini, N., Vannini, L., Jeffery, I. B., La Storia, A., Laghi, L., Serrazanetti, D. I., Di Cagno, R., Ferrocino, I., Lazzi, C., Turroni, S., Cocolin, L., Brigidi, P., Neviani, E., Gobbetti, M., O'Toole, P. W., & Ercolini, D.
Affiliations
  • University of Parma (IT)
  • University of Bologna (IT)
  • University College Cork (IE)
  • University of Turin (IT)
  • University of Bari Aldo Moro (IT)
  • University of Naples Federico II (IT)
Corresponding author
Ercolini, Danilo
ORCID
Venue
Gut
Publisher
BMJ
Published
2015-09-28
Volume
65
Issue
11
Pages
1812-1821
ISSN
  • 0017-5749 (ISSN-L)
  • 1468-3288
DOI
10.1136/gutjnl-2015-309957
OpenAlex
W2214388745
Cited by
1,638
References
73
Citations by year
2026: 153 · 2025: 177 · 2024: 167 · 2023: 180 · 2022: 207 · 2021: 239 · 2020: 182 · 2019: 142 · 2018: 87 · 2017: 62 · 2016: 38 · 2015: 1 · 2014: 1
FWCI
27.20
Type
journal article
Language
en
Open access
Locations
  • Gut (publishedVersion)
  • PubMed (publishedVersion)
  • Institutional Research Information System (University of Udine) (submittedVersion)
  • Archivio istituzionale della ricerca (Alma Mater Studiorum Università di Bologna) (submittedVersion)
  • Institutional Research Information System University of Turin (University of Turin) (submittedVersion)
  • HighWire Press Open Archive (submittedVersion)
  • CINECA IRIS Institutional Research Information System (University of Bari Aldo Moro) (submittedVersion)
  • Open Research (University of Surrey) (submittedVersion)
  • INFM-OAR (INFN Catania) (submittedVersion, other-oa)
Funders
  • Science Foundation Ireland
  • Ministero dell’Istruzione, dell’Università e della Ricerca (2010WZ2NJN, PRIN 2010-2011 “, 2010-2011, (PRIN 2010))
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Gut microbiota and health
  • Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Nutritional Studies and Diet
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Nutrition, Genetics, and Disease
Keywords
Mediterranean diet, dietary adherence, gut microbiota, metabolome, vegetarian diet, vegan diet, omnivorous diet, short-chain fatty acids, Prevotella, trimethylamine N-oxide, plant-based diet, Western diet, fecal metabolites, urinary metabolites
MeSH terms
Gastrointestinal Microbiome, Adult, Cross-Sectional Studies, Dietary Fiber, Fatty Acids, Feces, Feeding Behavior, Female, Humans, Male, Methylamines, Patient Compliance, Statistics as Topic, Vegetables, Prevotella, Diet, Mediterranean, Gastrointestinal Tract, Healthy Volunteers

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-07.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-07.

Statistics and arithmetic are recomputed, not judged.

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