Research

Mixed

Bariatric surgery induces significant lean body mass (LBM), fat-free mass (FFM), and skeletal muscle mass (SMM) loss, with approximately 55% of LBM loss occurring within the first 3 months post-surgery.

If you undergo bariatric surgery, expect to lose about 8 kg of lean body mass within the first year, with more than half of that loss happening in the first 3 months. This is not just fat loss; it includes muscle. To protect your metabolism and function, you must prioritize protein intake and resistance training immediately after surgery, not just focus on calorie restriction.

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At 12-month postsurgery, pooled LBM loss was -8.13 kg... About 55% of 12-month LBM loss occurred within 3-month postsurgery, followed by a more gradual decrease up to 12 months.
Malou A. H. Nuijten et al. · Obesity Reviews · 2021

Why this rating

Systematic review and meta-analysis of 59 studies.

Source

The magnitude and progress of lean body mass, fat‐free mass, and skeletal muscle mass loss following bariatric surgery: A systematic review and meta‐analysis

Malou A. H. Nuijten et al. · Obesity Reviews · 2021

Meta-analysis · 59 studiesCited 207×
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