The Claim

In obese adults aged 59.3 ± 9.1 years, a 12-week hypocaloric meal replacement program was associated with a significant increase in rectus femoris muscle area and muscle thickness, despite concurrent reductions in body weight and fat mass.

Source: Preservation of muscle mass assessed by ultrasound during a meal replacement-based hypocaloric intervention in obese individuals: a real-world clinical trial.

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
40score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Correlation
1 study reviewed
In plain English

In older obese adults, a 12-week low-calorie meal replacement diet led to measurable increases in thigh muscle size and thickness, even as overall body weight and fat decreased.

See the scientific wording

In obese adults aged 59.3 ± 9.1 years, a 12-week hypocaloric meal replacement program was associated with a significant increase in rectus femoris muscle area (from 4.40 ± 0.6 cm² to 5.86 ± 0.4 cm², p = 0.04) and muscle thickness (from 1.70 ± 0.3 cm to 2.32 ± 0.3 cm, p = 0.03), despite concurrent reductions in body weight and fat mass, suggesting that muscle preservation may occur during weight loss with this dietary approach.

Why this might work

When calories are reduced but protein intake is maintained, the body shifts to using fat for energy instead of breaking down muscle. This keeps muscle proteins from being destroyed and allows new muscle proteins to be made, making the muscle thicker.

Supported mechanismbased on 1 study

What the research says

1 study
  1. Study: Preservation of muscle mass assessed by ultrasound during a meal replacement-based hypocaloric intervention in obese individuals: a real-world clinical trial.

    In older adults with obesity, swapping one meal a day with a special shake for 12 weeks made their thigh muscles thicker, even though they lost weight and fat. This means the diet didn’t just shrink them—it helped their muscles grow or stay strong.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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