Does Vitamin K with Glucagon-like peptide-1 (GLP-1) analogs help with weight loss?

Vitamin K with GLP-1 Receptor Agonists for Weight Loss

There is no evidence that vitamin K supplementation enhances weight loss when combined with GLP-1 receptor agonists. According to the 2024 American Diabetes Association Standards of Care, despite widespread marketing claims, there is no clear evidence that nutrition supplements (including vitamins) are effective for obesity management or weight loss 1.

GLP-1 Receptor Agonists and Weight Loss

GLP-1 receptor agonists are highly effective for weight loss on their own:

• Efficacy ranking: Tirzepatide can produce up to 17.8% weight loss after 72 weeks, semaglutide up to 13.9% after 68 weeks, and liraglutide up to 5.8% after 26 weeks 2
• Mechanism: GLP-1 receptor agonists promote weight loss through:
  • Increased satiety and reduced appetite
  • Delayed gastric emptying
  • Modest reduction in systolic blood pressure (1-6 mmHg)
  • Reduction in LDL cholesterol (up to 16%) 1

Vitamin Supplements and Weight Loss

The 2024 ADA guidelines explicitly state:

• "Despite widespread marketing and exorbitant claims, there is no clear evidence that nutrition supplements (such as herbs and botanicals, high-dose vitamins and minerals, amino acids, enzymes, antioxidants, etc.) are effective for obesity management or weight loss" 1
• "Several large systematic reviews show that most trials evaluating nutrition supplements for weight loss are of low quality and at high risk for bias" 1
• "High-quality published studies show little or no weight loss benefits" 1

Recommended Approach for Weight Loss

For patients seeking weight loss, particularly those with diabetes or obesity, the evidence-based approach includes:

1. First-line pharmacotherapy: Use GLP-1 receptor agonists with proven weight loss efficacy:

   • Semaglutide or tirzepatide are preferred due to greater weight loss efficacy and cardiometabolic benefits 1
   • These medications can produce significant weight loss (10-20%) when used at appropriate doses 3

2. Lifestyle modifications:

   • Reduced calorie diet
   • Increased physical activity (150-300 min/week) 1
   • Behavioral support

3. Monitoring and follow-up:

   • Evaluate efficacy after 12 weeks on maximum tolerated dose
   • Consider discontinuation if <5% weight loss is achieved 3

Common Side Effects and Management

• Gastrointestinal effects: Nausea, vomiting, diarrhea, constipation (47-84% of patients) 3, 2

  • Manage with gradual dose titration
  • Educate patients to reduce meal size

• Other considerations:

  • GLP-1 receptor agonists may increase heart rate
  • Use with caution in patients with history of gallbladder disease or pancreatitis 3
  • Regular monitoring of renal function is recommended 3

Conclusion

Adding vitamin K to GLP-1 receptor agonist therapy has no scientific basis for enhancing weight loss. Patients seeking weight loss should focus on evidence-based approaches including appropriate dosing of GLP-1 receptor agonists, caloric restriction, and increased physical activity rather than unproven supplement combinations.