Long-term weight maintenance after a low-carbohydrate diet: a real-world retrospective cohort study

Low-carbohydrate diet (LCD) promotes short-term weight loss in individuals with overweight or obesity, but long-term maintenance remains uncertain, particularly in real-world settings. This study aimed to identify predictors of weight regain following a short-term LCD intervention in a hospital-based weight management program.

This retrospective cohort study included adult individuals with overweight or obesity (BMI ≥ 24 kg/m²) who underwent an LCD between July 2016 and July 2020. Baseline anthropometric and metabolic data were extracted from medical records, and follow-up weight and lifestyle information were collected via structured telephone interviews and questionnaires at least 12 months post-intervention. Weight regain was defined as regaining ≥25% of initial weight loss. Multivariable logistic regression identified independent predictors of weight regain, adjusting for age, sex, and other confounders.

Among 294 participants, all subjects received an LCD intervention for an average of 6.9 ± 4.2 weeks, and the average follow-up duration was 36.7 months. Of these, 153 (52%) regained weight, while 141 (48%) maintained weight loss. Despite a higher initial BMI (30.6 ± 5.3 vs. 29.1 ± 4.4 kg/m², p = 0.008), maintainers exhibited greater long-term stability. A family history of obesity significantly increased weight regain risk (OR = 2.36-2.84, p < 0.01), whereas adequate sleep (6-8 h/night) was protective (OR = 0.15-0.16, p < 0.05). LCD duration, initial weight loss, and exercise frequency were not consistently associated with maintenance.

Both genetic predisposition and lifestyle factors influence long-term weight outcomes, underscoring the interplay between immutable and modifiable determinants in weight management.