Research

Energy balance

In patients with type 2 diabetes, a very low-calorie diet (VLCD) of 500 kcal/day achieves early improvements in insulin sensitivity and beta-cell function equivalent to Roux-en-Y gastric bypass (RYGB) when matched for the rate and magnitude of weight loss.

For patients with type 2 diabetes, achieving a very low-calorie intake (around 500 kcal/day) for about three weeks can restore insulin sensitivity and beta-cell function just as effectively as gastric bypass surgery, provided the weight loss is rapid and significant. This suggests that the early metabolic 'reset' is driven by the intensity of caloric restriction rather than surgical changes to the gut.

GoodSupportsHIGH confidence
Based on these data, VLCD improves insulin sensitivity and b-cell function just as well as RYGB in the short term.
Clifton Jackness et al. · Diabetes · 2013

Why this rating

Randomized controlled trial design with matched cohorts, though limited by small sample size (n=25) and short duration (21 days).

Source

Very Low–Calorie Diet Mimics the Early Beneficial Effect of Roux-en-Y Gastric Bypass on Insulin Sensitivity and β-Cell Function in Type 2 Diabetic Patients

Clifton Jackness et al. · Diabetes · 2013

DOI 10.2337/db12-1762

rct · n=25Cited 265×
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DOI resolved against Crossref · corpus check 2026-06-10

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