The Claim
In Japanese adults with overweight or obesity, a 12-week web-based intermittent fasting program with weekly meal replacements caused a mean reduction of 1.3 kg in muscle mass compared to a control group, without concomitant fat loss.
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
Among Japanese adults with overweight or obesity, a 12-week web-based intermittent fasting program that included weekly meal replacements resulted in an average loss of 1.3 kilograms of muscle mass compared to a control group, with no corresponding loss of fat mass.
See the scientific wording
In Japanese adults with overweight or obesity, a 12-week web-based intermittent fasting program with weekly meal replacements resulted in a mean reduction of 1.3 kg in muscle mass compared to control, suggesting the intervention may promote lean tissue loss without concomitant fat loss.
When the body gets less energy than it needs, it breaks down muscle tissue to use the protein for fuel, while also slowing down the process that builds new muscle. This causes muscle mass to shrink even when fat stores remain unchanged.
What the research says
1 studyPeople who followed this specific fasting plan with meal replacements lost about 1.3 kg of muscle, but didn’t lose much fat — so most of the weight they lost came from muscle, not fat.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.