28th February 2024

Benefits of the 5:2 Diet

Fasting just two days a week has been found to yield the same health benefits as continuous calorie restriction and is a form of intermittent fasting that focuses on which days you eat. The benefits of a 5:2 diet are extensive, so keep reading for your full guide to the benefits of a 5:2 diet, and what a typical non-fasting day would look like to help get you started.

What is the 5:2 diet? 

The 5:2 diet is a form of intermittent fasting that involves consuming 800 calories two days a week (known as fasting days) and eating a balanced diet without calorie counting on the other five days, just sensible portion control and Mediterranean-style meals (known as non-fasting days). On fasting days, the body enters a state of ketosis much like it does on a keto diet, whereby switching to burning its fat stores for fuel rather than glucose found most readily in carbohydrates, which is why it’s so effective for weight loss. 

For fasting days, people generally choose to either eat three small meals or two larger meals. It’s important to prioritise eating protein, fibre and healthy fats on fasting days to stay properly nourished and energised, and to reap the full benefits of a 5:2 diet.

On non-fasting days, it must still be noted that you cannot simply eat anything; eating junk food or ultra-processed food will negate many of the benefits of the 5:2 diet, and may even result in weight gain.


Enjoy 5:2 meal plans and over 700 delicious, low-carb recipes with our Programme. Designed to support you on your journey to sustainable weight loss and better health.


Benefits of the 5:2 diet

There are plenty of benefits of a 5:2 diet. One key benefit for many is that it’s often easier to follow than continuous calorie restriction, resulting in a less restrictive route to success for those wanting to have a healthier lifestyle. Additionally, the 5:2 lifestyle can be followed long term to keep reaping the benefits, rather than only being suitable for a set number of weeks like a ketogenic diet or The Very Fast 800

The 5:2 diet was founded by Dr Michael Mosley when he was diagnosed with type 2 diabetes, and within just 12 weeks of following the lifestyle, he had lost nearly 9 kgs and reduced his blood sugars to within a healthy range, so the results truly speak for themselves. Aside from individual success stories, countless studies have found many other phenomenal benefits of a 5:2 diet

  • It improves your insulin response, reducing your risk of type 2 diabetes1
  • It activates autophagy for cell regeneration2
  • It improves metabolism efficiency3
  • It may reduce the risk of various cancers, including breast cancer4
  • It can be more effective for weight loss than continuous calorie restriction, particularly for visceral fat loss5
  • It may delay neurological disorders such as dementia, Parkinson’s and strokes6
  • It may reduce risk of cardiovascular disease7

It’s clear that the benefits of a 5:2 diet are extensive, so what should you be eating when following this lifestyle?

A typical non-fasting day following a 5:2 diet

For a little inspiration for your non-fasting days, here’s a peek at a day’s meals you can enjoy when not counting the calories:

BreakfastChocolate Protein Porridge
Porridge is an excellent way to kick off your non-fasting days, particularly if you make a few tweaks to improve its nutritional content. This recipe is packed full of fibre, healthy fats and antioxidants to keep you going all morning. Each portion serves up almost half your daily recommended protein, and with that rich, chocolate flavour, who could resist?

LunchBroccoli, Ginger, Coriander Soup
This Thai green curry-inspired soup is a keto-friendly option to enjoy on either fasting or non-fasting days. It’s ideal for cooking up in large batches to cater for other non-fasting day lunches, and contains all the key nutrients you need to keep you on track for a healthy lifestyle.

Dinner High Fibre Carne Asada Tacos
This Mexican dish is perfect for the whole family to enjoy on your non-fasting days. The ‘complete’ form of protein at the heart of the recipe, beef steak, helps protect you from a variety of chronic health conditions, which in turn adds to the benefits of a 5:2 diet. Providing over a third of your recommended fibre intake, this recipe is going to help keep your gut microbiome happy and healthy while fasting, too.

This day’s meals contained a whopping combined 84.4g protein and 28.1g fibre. Plus, make sure on both fasting and non-fasting days you’re adding plenty of vegetables alongside your meals to boost the fibre further, add in extra vitamins and minerals, and keep you fuller for longer!

A simple way to get started

To gain access to plenty of delicious recipes (and lots of weight loss tools and resources), head to The Fast 800 Programme. The Programme houses more than 700 recipes, with options for both fasting and non-fasting days, with helpful meal planning tools to make lifestyles like a 5:2 that much easier. Our 5:2 meal plans are available for those following vegetarian and non-vegetarian diets and have all been carefully created by our in-house nutritionist. If you’d like to, you can modify your meal plans to suit your taste so that no matter your preferences or needs, the 5:2 can work for you. 

Sign up for your 7-day free trial of the Programme today, and begin your 5:2 journey assured that you’re nourishing your body and reaping all the benefits of a 5:2 diet in an enjoyable and accessible way


Mattson MP, Longo VD, Harvie M. Impact of intermittent fasting on health and disease processes. Ageing Res Rev. 2017 Oct;39:46-58. doi: 10.1016/j.arr.2016.10.005. Epub 2016 Oct 31. PMID: 27810402; PMCID: PMC5411330.

As above

As above

Tiwari S, Sapkota N, Han Z. Effect of fasting on cancer: A narrative review of scientific evidence. Cancer Sci. 2022 Oct;113(10):3291-3302. doi: 10.1111/cas.15492. Epub 2022 Aug 10. PMID: 35848874; PMCID: PMC9530862.

Harvie MN, Pegington M, Mattson MP, Frystyk J, Dillon B, Evans G, Cuzick J, Jebb SA, Martin B, Cutler RG, Son TG, Maudsley S, Carlson OD, Egan JM, Flyvbjerg A, Howell A. The effects of intermittent or continuous energy restriction on weight loss and metabolic disease risk markers: a randomized trial in young overweight women. Int J Obes (Lond). 2011 May;35(5):714-27. doi: 10.1038/ijo.2010.171. Epub 2010 Oct 5. PMID: 20921964; PMCID: PMC3017674.

Mattson MP, Longo VD, Harvie M. Impact of intermittent fasting on health and disease processes. Ageing Res Rev. 2017 Oct;39:46-58. doi: 10.1016/j.arr.2016.10.005. Epub 2016 Oct 31. PMID: 27810402; PMCID: PMC5411330.

As above

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