The effect of lifestyle interventions on excess ectopic fat deposition measured by non-invasive techniques in overweight and obese adults : a systematic review and meta-analysis
Faculty of Medicine and Health Sciences
Journal of Physical Activity and Health
, p. 1-19
University of Antwerp
Background: Reduction of ectopic fat accumulation plays an important role in the prevention of insulin resistance in people with overweight or obesity. This systematic review and meta-analysis summarizes the current evidence for the use of non-invasive weight loss interventions (exercise or diet) on ectopic fat. Methods: A systematic literature search was performed according to the PRISMA statement. Clinical trials in PubMed, PEDro, and the Cochrane database were searched. Results: All 33 included studies described the effect of lifestyle interventions on ectopic fat storage in internal organs (liver, heart and pancreas) and intramyocellular lipids (IMCL), hereby including 1146, 157, 87 and 336 participants. Overall, a significant decrease of ectopic fat was found in liver (-0.53 Hedges g, p<0.001), heart (- 0.72 Hedges g, p<0.001) and pancreas (-0.55 Hedges g, p = 0.098) respectively. A trend towards decrease in IMCL was also observed. Meta-regression indicated a dose-response relationship between BMI reduction and decreased hepatic adiposity. Exercise alone decreased ectopic fat but the effect was greater when combined with diet. Conclusion: Lifestyle interventions can reduce ectopic fat accumulation in the internal organs of overweight and obese adults. The results on IMCL should be interpreted with care, keeping the athletes paradox in mind.