Even with lots of coaching, people can’t stick perfectly to diets that require them to eat a lot more protein or less fat—most end up eating closer to their old habits, but still lose weight.
Evidence Quality Assessment
Claim Status
appropriately stated
Study Design Support
Design supports claim
Appropriate Language Strength
definitive
Can make definitive causal claims
Assessment Explanation
The study used objective dietary recalls and biomarkers to quantify adherence deviations, allowing definitive statements about the magnitude of non-adherence under controlled conditions.
Gold Standard Evidence Needed
According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.
Evidence from Studies
Supporting (1)
Comparison of weight-loss diets with different compositions of fat, protein, and carbohydrates.
Even though people were told exactly what percentage of fat, protein, and carbs to eat for two years — and got lots of help — they didn’t stick to it well, and everyone lost about the same amount of weight anyway. This means it’s hard to follow strict diet rules long-term.