This study aims to evaluate the impact of low-carbohydrate diet, balanced dietary guidance, and pharmacotherapy on weight loss among individuals with overweight or obesity over a period of three months. The study involves 339 individuals with overweight or obesity and received weight loss treatment at the Department of Clinical Nutrition at the Second Affiliated Hospital of Zhejiang University, School of Medicine, between January 1st, 2020 and December 31st, 2023. The primary outcome is the percentage weight loss. Among the studied patients, the majority chose low-carbohydrate diet as their primary treatment (168 [49.56%]), followed by balanced dietary guidance (139[41.00%]) and pharmacotherapy (32 [9.44%]). The total percentage weight loss for patients who were followed up for 1 month, 2 months, and 3 months was 4.98 (3.04,6.29) %,7.93 (5.42, 7.93) % and 10.71 (7.74,13.83) %, respectively. Multivariable logistic regression analysis identified low-carbohydrate diet as an independent factor associated with percentage weight loss of ≥3% and ≥5% at 1 month (OR [odds ratio] =0.461, P＜0.05; OR=0.349, P＜0.001). The results showed that a low-carbohydrate diet was an effective weight loss strategy in the short term. However, its long-term effects were comparable to those observed with balanced dietary guidance and pharmacotherapy.