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What is Low Calorie Diet?

A low calorie diet is a clinically proven diet plan that involves eating about 800 calories a day or fewer. They are considered for overweight and obese people who are managing diabetes.

Discover Our Diet Plans

OPTIFAST offers several plans for you to choose from, depending on your weight loss goals and your personal lifestyle.

Best Selling
6 Weeks Diet Plan

Our Six-Week Plan was developed for people who
want to lose weight on their own, using a clear framework.

Save £103 on our best selling 6 week diet plan.

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The Popular
Intermittent Fasting Plan

Our Intermittent Fasting Plans cycle between periods of
fasting and eating, so they’re flexible to fit around your lifestyle.

For just £2 per meal, weight loss in just 4 weeks!

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Key Benifits

The Most Flexible
Meal Replacement Plan

Our Partial Meal Replacement Plan is our most flexible option.

Save £86 on your first 2 weeks diet plan, with just £ 1.95 per meal

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Maintain Your Desired
Weight For Good

Our Maintenance Plan is designed to help you to maintain
your desired body weight, particularly after weight loss.

Enjoy 28% off on 8 weeks maintenance diet plan, for just £1.84 per meal.

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Want To Find Your Perfect Diet Plan?

To help you decide which diet plan is perfect for you,
Click below to Calculate your BMI and discover our recommended plan for you.

Find Your Plan Now
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Supported by Science

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

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