Hallberg 2018: Virta Health Type 2 Diabetes Reversal

Background

Dr. Sarah Hallberg, Dr. Stephen Phinney, and colleagues from Virta Health and Indiana University published this landmark study in Diabetes Therapy (PMID: 29417495), demonstrating diabetes reversal through nutritional ketosis.

Study Design

Design: Non-randomized controlled trial with continuous care intervention Population: 262 adults with type 2 diabetes (intervention) vs. 87 usual care controls Intervention: Carbohydrate restriction (<30 g/day initially) with remote monitoring, physician support, and health coaching Duration: 1 year Primary endpoints: HbA1c, medication changes, weight

Key Findings

Outcome	Virta Intervention	P value
HbA1c reduction	−1.3% (from 7.6% to 6.3%)	<0.001
Diabetes reversal (A1c <6.5% off meds)	60%	—
Insulin users who reduced/eliminated	94%	—
Weight loss	−12% (−14 kg)	<0.001
Retention at 1 year	83%	—

Medication reductions:

• •94% reduced or eliminated insulin
• •50% eliminated sulfonylureas
• •Metformin often continued for metabolic benefits

Mechanistic Insights

Carbohydrate restriction addresses the fundamental defect:

1. •Reduces glucose load requiring insulin
2. •Lowers hepatic glucose output
3. •Improves insulin sensitivity
4. •Reduces ectopic fat (liver, pancreas)

Nutritional ketosis provides alternative fuel, reducing glucose dependence.

Clinical Implications

Type 2 diabetes can be reversed without surgery or intensive medication. The continuous care model provides scalable support. Long-term sustainability requires ongoing behavioral support.

Metabolic Health Perspective

This study validated carbohydrate restriction as first-line therapy for type 2 diabetes, demonstrating that the disease process can be reversed, not just managed.