Research

Energy balance

Very-low-calorie diets (VLCD, 400-800 kcal/d) under medical supervision produce approximately 20 kg of weight loss in 12-16 weeks, but long-term maintenance is poor without additional behavioral or exercise interventions.

VLCDs (400-800 kcal) can produce rapid weight loss (~20kg in 3-4 months) but require medical supervision. They are not a standalone long-term solution; combining them with behavior therapy or exercise significantly improves the chance of keeping the weight off.

GoodQualifiesHIGH confidence
Patients treated under medical supervision using a very-low-calorie diet (400 to 800 kcal/d) lose approximately 20 kg in 12 to 16 weeks and maintain one half to two thirds of this loss in the following year.
Thomas A. Wadden · Annals of Internal Medicine · 1993

Why this rating

Based on randomized clinical trials and follow-up data.

Source

Treatment of Obesity by Moderate and Severe Caloric Restriction: Results of Clinical Research Trials

Thomas A. Wadden · Annals of Internal Medicine · 1993

DOI 10.7326/0003-4819-119-7_part_2-199310011-00012

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DOI resolved against Crossref · corpus check 2026-06-10

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