Research

Energy balance

Very low energy diets (VLEDs) defined as <3.4 MJ (800 kcal)/day with full nutritional allowances produce rapid, significant short-term weight loss (1.5–2.5 kg/week) and improve metabolic markers, but do not achieve significantly better long-term weight maintenance compared to conventional low-calorie diets.

A Very Low Energy Diet (VLED) involves consuming less than 800 calories daily for 8-16 weeks, ensuring you get all necessary vitamins and protein. This approach leads to rapid weight loss (1.5-2.5 kg/week) and can significantly improve conditions like type 2 diabetes and hypertension. However, it is not a magic bullet for long-term maintenance; without cognitive behavioral counseling and lifestyle changes, weight regain is common. It is safe for most obese adults with medical supervision but is contraindicated for normal-weight individuals, pregnant women, and those with severe organ disease.

GoodQualifiesHIGH confidence
Very low energy diets (VLEDs) are defined as diets which contain energy levels of less than 3.4 MJ (800 kcal) per day and contain daily allowances of all essential nutritional requirements... which usually achieves a weight loss of 1.5–2.5 kg per week... Programmes using VLEDs produce better short-term weight loss than programmes without the diet. However, in randomized controlled trials VLED-based programmes have not achieved significantly better long-term maintenance than conventional programmes.
Pertti Mustajoki et al. · Obesity Reviews · 2001

Why this rating

Based on a systematic review of randomized controlled trials (RCTs) and clinical guidelines, though long-term maintenance data is mixed.

Source

Very low energy diets in the treatment of obesity

Pertti Mustajoki et al. · Obesity Reviews · 2001

DOI 10.1046/j.1467-789x.2001.00026.x

narrative_reviewCited 119×
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DOI resolved against Crossref · corpus check 2026-06-10

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