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The Science That Makes It Work

Developed by scientists, widely researched and tested, OPTIFAST is a clinically proven, scientifically designed very low calorie diet recommended for weight loss.

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A Weight Loss Approach You Can Trust

With so many different weight loss options to choose from, it's hard to know if you have selected a safe and effective option.

One way to know is to make sure your chosen weight loss solution has a strong scientific basis, like the OPTIFAST Program.

The OPTIFAST Program is clinically proven, nutritionally complete & balanced and recommended by healthcare professionals for the dietary management of obesity.

The OPTIFAST VLCD Program can help you achieve fast and effective weight loss with a flexible 3, 2, 1 step program

Weight loss has been shown to help improve health outcomes:

Improve blood glucose control1
Improve blood pressure control2
Improve quality of life1
Reduce blood cholesterol2
Reduce the pain associated with osteoarthritis3
A specialist showing the women ingredients information on OPTIFAST Meal Replacement Vanilla Shake

Clinically Proven Benefits

OPTIFAST VLCD is a very low calorie diet program, backed by over 80 clinical publications, demonstrating safe and effective weight loss.

A woman putting a meal replacement shake powder into the shaker bottle.

Nutritionally balanced products

OPTIFAST VLCD products are based on scientifically designed recipes developed by a team of experts. We provide a program that is nutritionally complete and balanced, proven to help you reach and maintain your weight loss goal. The OPTIFAST team regularly renovate OPTIFAST VLCD products to reflect the most current opinion on the science of weight loss. OPTIFAST VLCD products can be used as part of a total diet replacement which includes all of the nutrients you need including protein, vitamins and minerals.

A health professional

Recommended by healthcare professionals around the world for safe and effective weight loss

We work closely with our expert multidisciplinary OPTIFAST VLCD Advisory Board to ensure that the OPTIFAST Program is in line with current evidence-based guidelines and regulations.  We offer training for healthcare professionals including dietitians, nurses and doctors on the benefits of the OPTIFAST Program, and how to implement the OPTIFAST Program effectively for their patients and clients.

Find a Dietitian Directory - COMING SOON. In the meantime, please contact us at to enquire as to your closest OPTIFAST Dietitian.


  1. Lean M.E.J., et al. Lancet 2018; 391: 541-51
  2. Anderson, J.W., et al. J American College of Nutrition, 2003. 22(5): p.331-339
  3. Reicke, B.F.., et al. Osteoarthritis Cartilage, 2010. 18(6):p. 746-54