Adherence
Adherence, not diet type, determines weight loss and cardiac risk reduction outcomes in popular diets.
Stop obsessing over which specific diet plan you follow. The data shows that whether you choose Atkins, Zone, Weight Watchers, or Ornish, the weight loss and heart health benefits are statistically identical if you stick with it. Your success depends entirely on how well you adhere to the plan you choose, not the plan's name. Focus on building a sustainable routine you can maintain for a year, rather than searching for a 'magic' diet.
Amount of weight loss was associated with self-reported dietary adherence level (r=0.60; P<.001) but not with diet type (r=0.07; P=.40).
Why this rating
Randomized controlled trial with 160 participants, though high attrition (42%) and reliance on self-reported adherence introduce bias.
Source
Comparison of the Atkins, Ornish, Weight Watchers, and Zone Diets for Weight Loss and Heart Disease Risk Reduction
Michael L. Dansinger et al. · JAMA · 2005
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