Research

Mixed

Restrictive hypocaloric diets and bariatric surgery reduce total gut microbial abundance and decrease butyrate-producing bacteria (Firmicutes, Lactobacillus, Bifidobacterium), which may have long-term detrimental effects on the colon despite promoting weight loss.

While restrictive diets and bariatric surgery are effective for weight loss, they can negatively impact your gut microbiome by reducing beneficial bacteria that produce butyrate. To mitigate this, consider incorporating prebiotics or specific probiotics, which the review notes may restore a healthy microbiome and reduce body fat, rather than relying solely on caloric restriction or surgery for gut health.

GoodQualifiesHIGH confidence
These results show that restrictive diets and bariatric surgery reduce microbial abundance and promote changes in microbial composition that could have long-term detrimental effects on the colon.
Fernanda Braga Seganfredo et al. · Obesity Reviews · 2017

Why this rating

Based on a systematic review of 43 studies, including RCTs, though heterogeneity in methods is noted.

Source

Weight‐loss interventions and gut microbiota changes in overweight and obese patients: a systematic review

Fernanda Braga Seganfredo et al. · Obesity Reviews · 2017

DOI 10.1111/obr.12541

systematic_reviewCited 227×
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DOI resolved against Crossref · corpus check 2026-06-10

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