The Claim

Among obese adults initiating a protein-sparing modified fast, 55% achieve at least 5% weight loss at one year, compared to 20% of those on other diets; by five years, the proportion achieving at least 5% weight loss is similar between the two groups (34% vs. 29%).

Source: The Effect of Starting the Protein-Sparing Modified Fast on Weight Change over 5 years

What the research says

Supports is higher

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

Supports
59score
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.

Quantitative
1 study reviewed
In plain English

Among obese adults, 55% lose at least 5% of their body weight after one year on a protein-sparing modified fast, compared to 20% on other diets. After five years, both groups have similar rates of weight loss: 34% and 29% respectively.

See the scientific wording

Among obese adults initiating the protein-sparing modified fast, 55% achieve ≥5% weight loss at one year, compared to 20% of those choosing other diets, but by five years, the proportion achieving this level of loss is similar (34% vs. 29%).

Why this might work

When someone starts a very low-calorie diet with high protein, the body quickly breaks down fat stores for energy, causing fast weight loss. After a while, the body slows down its energy use and holds onto fat to survive, so weight loss stops even if the diet continues.

Supported mechanismbased on 1 study

What the research says

1 study
  1. Study: The Effect of Starting the Protein-Sparing Modified Fast on Weight Change over 5 years

    People who tried the PSMF diet lost at least 5% of their weight faster than those on other diets, but after five years, about the same number of people from both groups had kept off that weight. So the PSMF helps you lose weight quicker, but doesn’t help you keep it off better in the long run.

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

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