Research

Energy balance

A Low-Energy Diet (LED) of 850 kcal/day produces statistically equivalent weight loss and long-term maintenance compared to a Very-Low-Energy Diet (VLED) of 520 kcal/day, while offering a safer profile with fewer adverse events and reduced need for medical monitoring.

You do not need to eat fewer than 800 calories a day to lose weight effectively. A structured 850-calorie liquid diet program produces the same amount of weight loss and long-term maintenance as a more extreme 520-calorie diet, but with fewer side effects like fatigue and hair loss. Focus on a sustainable plan that includes behavioral support rather than trying to minimize calories as low as possible.

ModerateRefutesMEDIUM confidence
VLED did not produce a greater weight loss than the LED. LED provides similar weight loss with a lower incidence of adverse events and diminished need for medical monitoring. We conclude LED is an efficacious, safe, and less burdensome diet compared to VLED.
Bruce W. Bailey et al. · Disease Management · 2008

Why this rating

Large sample size (n=1887) and long-term follow-up (48 weeks), but the study is a retrospective analysis of self-selected groups, not a randomized controlled trial.

Source

Weight Loss and Maintenance Outcomes Using Moderate and Severe Caloric Restriction in an Outpatient Setting

Bruce W. Bailey et al. · Disease Management · 2008

DOI 10.1089/dis.2007.0002

cohort · n=1887Cited 11×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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