Comparison of the low-calorie DASH diet and a low-calorie diet on serum TMAO concentrations and gut microbiota composition of adults with overweight/obesity: a randomized control trial

Abstract

This study compares two diets, Dietary Approaches to Stop Hypertension (DASH) and a Low-Calorie Diet on Trimethylamine N-oxide (TMAO) levels and gut microbiota. 120 obese adults were randomly allocated to these three groups: a low-calorie DASH diet, a Low-Calorie diet, or a control group for 12 weeks. Outcomes included plasma TMAO, lipopolysaccharides (LPS), and gut microbiota profiles. After the intervention, the low-calorie DASH diet group demonstrated a greater decrease in TMAO levels (-20 ± 8.1 vs. −10.63 ± 4.6 μM) and a significant decrease in LPS concentration (-19.76 ± 4.2 vs. −5.68 ± 2.3) compared to the low-calorie diet group. Furthermore, the low-calorie DASH diet showed a higher decrease in the Firmicutes and Bactericides (F/B) ratio, which influenced TMAO levels, compared to the Low-Calorie diet (p = 0.028). The current study found the low-calorie DASH diet improves TMAO and LPS in comparison to a Low-Calorie diet.

Keywords:

• Trimethylamine N-oxide
• DASH diet
• obesity
• caloric restriction
• cardiovascular disease risk factors
• gut microbiome
• lipopolysaccharides

Acknowledgements

We would like to thank the Kermanshah University of Medical Sciences, Iran. Funding organization or sponsor has no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

Author contributions

JM designed the study; JM conducted the study and collected the data. HLF performed the statistical analysis. JM, and SM drafted the manuscript. ZD contributed to the revision of final version of the manuscript and the language editing, and analysing data as well. All the authors have read and approved the final version of the manuscript.

Disclosure statement

The authors declare no conflicts of interest.

Ethics approval and consent to participate

The Ethics Committee of Kermanshah University of Medical Sciences approved the study (code: KUMS.REC.1392.308). All methods were carried out in accordance with relevant guidelines and regulations. All the participants were provided oral and written informed consent.

Availability of data and materials

The datasets analysed during the current study are not publicly available due to ethical concerns of participants but are available from the corresponding author at reasonable request.

Additional information

Funding

This research was partially supported by the Kermanshah University of Medical sciences ((grant number 990527).