High intake of dietary fructose in overweight/obese teenagers associated with depletion of Eubacterium and Streptococcus in gut microbiome

Gut Microbes. 2019 Apr 16:1-8. doi: 10.1080/19490976.2019.1592420.

Jones RB, Alderette TL, Kim JS, et al.

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  • To determine how dietary macronutrients are associated with the relative abundance of gut bacteria in healthy adolescents.


  • A western high fat, high carbohydrate diet has been shown to be associated with decreased gut bacterial diversity and reductions in beneficial bacteria.
  • This gut bacteria dysbiosis could develop in early life and contribute to chronic disease risk such as obesity, type 2 diabetes and non-alcoholic fatty liver disease.


  • Fifty-two obese participants, ages 12–19 years and primarily of Hispanic descent, were recruited for this study.  Each participant provided fecal samples for 16S rRNA gene sequencing.
  • Dietary macronutrients were assessed using 24-hour diet recalls and body composition was assessed using DEXA.
  • General regression models assuming a negative binomial distribution were used to examine the associations between gut bacteria and dietary fiber, saturated fat, unsaturated fats, protein, added sugar, total sugar and free fructose after adjusting for age, gender, race/ethnicity, body fat percentage, study and caloric intake.


  • Eubacterium and Streptococcus were inversely associated with dietary fructose intake.
  • There were no other significant associations between abundances of gut microbes and other dietary macronutrients, including fiber, fat, protein, total sugar or added sugar.


  • High dietary fructose was associated with lower abundance of the beneficial microbes Eubacterium and Streptococcus, which are involved with carbohydrate metabolism.
  • Additional research is needed in this area.

Points to Consider:

  • Given the small size, age and ethnicity of the sample, the generalizability of these results is limited.
  • Dietary Intake information was self-reported and collected via 24-hour diet recalls. Not only does this information not reflect overall dietary habits, this method of collection is subject to recall and reporting bias.