Elsevier

Clinical Nutrition

Volume 38, Issue 6, December 2019, Pages 2504-2520
Clinical Nutrition

Review
Dietary fat, the gut microbiota, and metabolic health – A systematic review conducted within the MyNewGut project

https://doi.org/10.1016/j.clnu.2018.12.024Get rights and content

Summary

Background and aims

Studies indicate that dietary fat quantity and quality influence the gut microbiota composition which may as a consequence impact metabolic health. This systematic review aims to summarize the results of available studies in humans on dietary fat intake (quantity and quality), the intestinal microbiota composition and related cardiometabolic health outcomes.

Methods

We performed a systematic review (CRD42018088685) following PRISMA guidelines and searched for literature in Medline, EMBASE, and Cochrane databases.

Results

From 796 records, 765 records were excluded based on title or abstract. After screening of 31 full-text articles six randomized controlled trials (RCT) and nine cross-sectional observational studies were included. Our results of interventional trials do not suggest strong effects of different amounts and types of dietary fat on the intestinal microbiota composition or on metabolic health outcomes while observational studies indicate associations with the microbiota and health outcomes. High intake of fat and saturated fatty acids (SFA) may negatively affect microbiota richness and diversity and diets high in monounsaturated fatty acids (MUFA) may decrease total bacterial numbers whereas dietary polyunsaturated fatty acids (PUFA) had no effect on richness and diversity.

Conclusions

High fat and high SFA diets can exert unfavorable effects on the gut microbiota and are associated with an unhealthy metabolic state. Also high MUFA diets may negatively affect gut microbiota whereas PUFA do not seem to negatively affect the gut microbiota or metabolic health outcomes. However, data are not consistent and most RCT and observational studies showed risks of bias.

Section snippets

Introduction and rationale

In recent years, the gut microbiota has emerged as a significant factor for the regulation of energy balance and has been shown to be associated with obesity and metabolic diseases. The gut microbiota plays an important role in polysaccharide fermentation and the production of short-chain fatty acids (SCFA) which can be metabolized or used for the de novo synthesis of glucose, lipids or bile acids [1], [2]. Additionally the gut microbiota is involved in the maintenance of barrier function of

Search strategy and in-/exclusion criteria

We performed a systematic literature review following Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines [21]. Our review protocol was registered on PROSPERO under the Registration Number CRD42018088685.

To identify studies we searched for literature in Medline via PubMed, EMBASE via the Elsevier platform, and the Cochrane databases via Wiley from their inception. All searches were performed on January 17, 2018 using a combination of subject and free-text

Results

Figure 1 shows the flow diagram of the screened and selected studies.

Fifteen studies were included in this systematic review. Table 1 summarizes the characteristics and results of the interventional studies and Table 2 of the observational studies included. Six of the studies evaluated dietary interventions [24], [25], [26], [27], [28], [29], five reviewed dietary records [30], [31], [32], [33], [34], [35], one investigated serum metabolites of fatty acids [36] and three applied a food

Discussion

To our knowledge, this is the first systematic review that compiles and provides effects/associations of dietary fat quantity and quality on/with the gut microbiota composition and cardiometabolic health in humans. Based on 15 included studies, our results of interventional trials do not suggest strong effects of dietary fat quantity or quality on the gut microbiota or on metabolic health outcomes while observational studies indicate associations with the gut microbiota and health outcomes. It

Funding

The MyNewGut project is financially supported by a grant from the EU 7th Framework Programme under Grant Agreement 613979. The EU is not liable for the content presented in this publication.

Conflict of interest

None

Acknowledgement

We would like to thank Lara Christianson for her valuable support in the systematic literature search and related presentation and Rieke Baumkötter for her support in further literature research and administration.

References (67)

  • J.H. Cummings et al.

    Role of intestinal bacteria in nutrient metabolism

    J Parenter Enteral Nutr

    (1997)
  • A.F. Pihl et al.

    The role of the gut microbiota in childhood obesity

    Child Obes

    (2016)
  • S.S. Pereira et al.

    Low-grade inflammation, obesity, and diabetes

    Clin Obes Rep

    (2014)
  • K. Korpela et al.

    Antibiotic use in childhood alters the gut microbiota and predisposes to overweight

    Microbial cell (Graz, Austria)

    (2016)
  • P.J. Turnbaugh et al.

    An obesity-associated gut microbiome with increased capacity for energy harvest

    Nature

    (2006)
  • S. Rampelli et al.

    Microbiota and lifestyle interactions through the lifespan

    Trends Food Sci Technol

    (2016)
  • G.D. Wu et al.

    Linking long-term dietary patterns with gut microbial enterotypes

    Science (New York, NY)

    (2011)
  • J. Alcock et al.

    Fatty acids from diet and microbiota regulate energy metabolism

    F1000Res

    (2015)
  • K. Kaliannan et al.

    Omega-3 fatty acids prevent early-life antibiotic exposure-induced gut microbiota dysbiosis and later-life obesity

    Int J Obes

    (2016)
  • F.H. Karlsson et al.

    Gut metagenome in European women with normal, impaired and diabetic glucose control

    Nature

    (2013)
  • M. Yassour et al.

    Sub-clinical detection of gut microbial biomarkers of obesity and type 2 diabetes

    Genome Med

    (2016)
  • J. Qin et al.

    A metagenome-wide association study of gut microbiota in type 2 diabetes

    Nature

    (2012)
  • H.V. Lin et al.

    Butyrate and propionate protect against diet-induced obesity and regulate gut hormones via free fatty acid receptor 3-independent mechanisms

    PLoS One

    (2012)
  • X. Zhang et al.

    Human gut microbiota changes reveal the progression of glucose intolerance

    PLoS One

    (2013)
  • A. Schwiertz et al.

    Microbiota and SCFA in lean and overweight healthy subjects

    Obesity

    (2010)
  • G. den Besten et al.

    The short-chain fatty acid uptake fluxes by mice on a guar gum supplemented diet associate with amelioration of major biomarkers of the metabolic syndrome

    PLoS One

    (2014)
  • D. Moher et al.

    Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement

    PLoS Med

    (2009)
  • J. Higgins et al.

    Cochrane handbook for systematic reviews of interventions (the Cochrane collaboration)

    (2011)
  • G.A. Wells et al.

    The Newcastle-Ottawa Scale (NOS) for assessing the quality of nonrandomised studies in meta-analyses, The Ottawa Hospital Research Institute

    (2011)
  • M. Balfego et al.

    Effects of sardine-enriched diet on metabolic control, inflammation and gut microbiota in drug-naive patients with type 2 diabetes: a pilot randomized trial

    Lipids Health Dis

    (2016)
  • T. Blædel et al.

    A randomised, controlled, crossover study of the effect of diet on angiopoietin-like protein 4 (ANGPTL4) through modification of the gut microbiome

    J Nutr Sci

    (2016)
  • F. Fava et al.

    The type and quantity of dietary fat and carbohydrate alter faecal microbiome and short-chain fatty acid excretion in a metabolic syndrome ‘at-risk’ population

    Int J Obes

    (2013)
  • C. Haro et al.

    Two healthy diets modulate gut microbial community improving insulin sensitivity in a human obese population

    J Clin Endocrinol Metab

    (2016)

    • Cited by (171)

    • A review of the interaction between diet composition and gut microbiota and its impact on associated disease

      2024, Journal of Future Foods

    • Potential associations between organic dairy products, gut microbiome, and gut health: A review

      2023, Food Research International

    • Understanding the impact of radical changes in diet and the gut microbiota on brain function and structure: rationale and design of the EMBRACE study

      2023, Surgery for Obesity and Related Diseases

    • Efficacy of low carbohydrate and ketogenic diets in treating mood and anxiety disorders: Systematic review and implications for clinical practice

      2023, BJPsych Open

    • The Effectiveness of Low-Carb Diet vs Low-Fat Diet on Body Composition in People with Obesity: A Literature Review

      2024, Amerta Nutrition

    • Gut microbiota in overweight and obesity: crosstalk with adipose tissue

      2024, Nature Reviews Gastroenterology and Hepatology
    View all citing articles on Scopus
    1

    Shared senior authorship.

    View full text
    © 2018 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.