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OPTIFAST Intermittent Fasting Diet Plan

Our Intermittent Fasting plan is designed to help you lose weight and maintain weight loss. It offers the flexibility to switch between periods of fasting and eating, without restricting your caloric intake for days in a row.

What is Intermittent Fasting?

Intermittent fasting is a flexible way to lose weight, alternating between periods of fasting and eating, without restricting your intake of calories for prolonged periods. Intermittent fasting can fit easily into your lifestyle and there are two different intermittent fasting routes to choose from using OPTIFAST products:

· The 5:2 Diet Plan - which includes five ‘feast’ days and two ‘fast’ days each week

· The Alternate Day Plan - which alternates ‘feast’ and fast days.

To learn more read our Guide to Intermittent Fasting:
Guide to Intermittent Fasting

What is the 5:2 Diet?

The 5:2 Diet is one way to do intermittent fasting, it involves ‘feasting’ for five days a week and fasting for two.

How to do the 5:2 Diet

On ‘feast’ days, you can eat conventional meals, up to a total of 1,200 calories a day for women and 1,500 calories a day for men. Discover low-calorie recipe inspiration.   

On fast days, you’ll consume four OPTIFAST products and no conventional foods. For example, you could have an OPTIFAST Bar for breakfast, an OPTIFAST Shake for lunch and an OPTIFAST Soup for dinner, followed by an OPTIFAST Dessert. 

Shop The 5:2 4 Week Plan

What is the Alternate Day Diet?

Alternate Day Fasting simply alternates fast and feast days one after the other.

How to do Alternate Day Fasting

On ‘feast’ days, you can eat conventional meals (up to a total of 1,200 calories a day for women and 1,500 calories a day for men).

On ‘fast’ days, you can enjoy four OPTIFAST meal replacement products, but no conventional foods.

Shop The Alternate Day 3 Week Plan

All you need to know in 60 seconds

Learn more about Intermittent Fasting

The 16:8 method of intermittent fasting is sometimes also referred to as 18:6 fasting or time-restricted fasting. With this type of intermittent fasting, your food intake will be restricted to an eight-hour window, followed by a total fast for 16 or 18 hours. 

This method of intermittent fasting can be a good option for helping to maintain your weight after completing a weight loss programme.

What you can eat during intermittent fasting depends on the specific diet plan you’re following. For example, the Eat Stop Eat diet plan allows you to continue eating the same foods that you usually do, whereas the 16:8 and 5:2 diet plans encourage you to reduce your daily calorie intake, focusing on lean protein and non-starchy fruit and veg. You might also choose to support your intermittent fasting plan with OPTIFAST meal replacement products

Everyone has different goals, which means everyone’s results will be different. You may find that you notice a difference in the way that you feel within the first week of changing your eating habits, but some people may not notice a change until they see a new number on the scales. Speak to a healthcare professional if you want support setting a realistic weight loss goal tailored to your individual needs.

Intermittent fasting can be a long-term healthy lifestyle change; some people like to continue with intermittent fasting after achieving their weight loss goals to help them to maintain their weight. Everyone’s goals are different, so you may just want to try intermittent fasting for a shorter period, before trying another diet plan, such as Partial Meal Replacement.

Always seek medical advice before undertaking a major change in your diet or lifestyle, particularly if you take medication or have a medical condition.

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