The Science Behind VLCDs: How Very Low Calorie Diets Really Work

When it comes to rapid and effective weight loss, Very Low Calorie Diets (VLCDs) have become a popular and medically recognised solution. But how do they actually work? Are they safe? And what results can you realistically expect?

In this blog post, we explore the science behind VLCDs, explain how they support fat loss, and break down why they're often recommended for those looking to kickstart significant weight loss—especially under medical supervision or structured plans like KeeDiet®.

🔬 What Is a VLCD?

A Very Low Calorie Diet typically involves consuming 800 calories or fewer per day. This is usually achieved through nutritionally complete meal replacements such as shakes, soups, or bars that are specially formulated to deliver essential vitamins, minerals, and protein—while significantly reducing your overall calorie intake.

Unlike crash diets or fad detoxes, VLCDs are backed by decades of clinical research and are often recommended in medical settings to treat obesity, manage type 2 diabetes, and reduce weight-related health risks.

🧠 How Do VLCDs Work?

The science is surprisingly straightforward:

• Calorie Deficit = Fat Burn
  VLCDs create a significant calorie deficit, forcing the body to burn stored fat for energy.
• Ketosis
  After a few days, your body may enter a mild state of ketosis, using fat for fuel and helping reduce hunger.
• Preserving Lean Muscle
  VLCDs are protein-rich to help preserve muscle mass, which is crucial for metabolism.
• Nutritional Balance
  Despite reduced calories, VLCDs are nutritionally complete—providing all essential nutrients.

✅ Are VLCDs Safe?

When used short-term and under guidance, VLCDs are considered safe and effective. They are often recommended for individuals with a BMI over 30, or those needing to lose weight before surgery or improve type 2 diabetes.

However, they’re not suitable for everyone. VLCDs should not be used during pregnancy, by those with certain medical conditions, or for extended periods without support. That’s why KeeDiet® offers tailored support to help you safely follow the right plan.

🧪 What Does the Research Say?

Clinical trials show VLCDs can lead to 1–2 stone weight loss in 8–12 weeks. A key study—the DiRECT Trial—found that VLCDs were effective in helping participants achieve remission of type 2 diabetes.

The results? Not just promising—life-changing.

💡 Final Thoughts

VLCDs are simple, structured, and scientifically sound. When followed correctly, they can help you take control of your weight, improve your health, and give you the kickstart you need.

Choose a trusted provider like KeeDiet®, where your health and success are our top priority.

🛒 Ready to Begin?

Explore our VLCD diet plans and bundles here →