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Changes in fat-free mass during significant weight loss: a systematic review
T B Chaston1, J B Dixon, P E O'Brien
1Australian Centre for Obesity Research and Education, Monash University, Monash Medical School, The Alfred Hospital, Melbourne, Victoria, Australia.
International Journal of Obesity (2005)
|November 1, 2006
Summary
Weight loss interventions impact fat-free mass (FFM) loss. Caloric restriction and surgery type significantly influence FFM loss, with certain bariatric procedures causing greater FFM reduction.
Area of Science:
- Metabolic health and body composition research.
- Obesity and weight management interventions.
Background:
- Understanding the impact of weight loss interventions on body composition is crucial for metabolic health.
- Fat-free mass (FFM) loss during weight reduction can have significant physiological consequences.
Purpose of the Study:
- To quantify the proportion of weight lost as FFM across diverse weight loss strategies.
- To compare FFM loss between dietary, behavioral, and surgical weight loss methods.
Main Methods:
- Systematic literature search of Medline and Embase for studies with >10 kg weight loss and FFM measurements.
- Pooled analysis using a fixed-effect model for % FFM loss/weight loss (%FFML).
- Linear regression to assess factors influencing %FFML, including caloric restriction, exercise, weight loss magnitude, BMI, and surgical type.
Main Results:
- Analysis included 26 cohorts for non-surgical and 29 for bariatric surgery interventions.
- Higher caloric restriction correlated with increased %FFML (r²=0.31, P=0.006).
- Biliopancreatic diversion (BPD) and Roux-en-Y gastric bypass (RYGB) resulted in greater %FFML compared to laparoscopic adjustable gastric banding (LAGB).
Conclusions:
- Caloric restriction, exercise, and weight loss rate affect FFM loss in non-surgical weight management.
- Bariatric surgeries like BPD and RYGB lead to a higher proportion of FFM loss than LAGB.
- These findings highlight the importance of intervention type in preserving FFM during significant weight loss.
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