5:2 Diet

The 5:2 diet is also called The Fast Diet. How does it work? You eat your regular diet on 5 days and, on the other two days, you lower calorie intake to 500 calories for a female and 600 calories for a male.

Intermittent Fasting: The 5:2 Diet

It was popularized by a British doctor and journalist Michael Mosley. It is important to note that at the beginning of 2017 Mosley relaxed the rules of the diet and currently allows 800 calories on the fasting day. The 5:2 diet has become not just a short periodic diet to lose weight, but also has been promoted as lifestyle or habit that tends to come naturally after patients try it.

Fasting is prevalent in many cultures and main religions too. Judaism has several annual fast days including Yom Kippur, the Day of Atonements; Muslims fast during the Ramadan. Eastern Orthodoxy and  Roman Catholics have a 40 day fast during Lent, the period when Christ fasted 40 days in the desert.

Furthermore, it was supported by many great minds in history for the health benefits too. It is known that Pythagoras (580-500 years. BC), Greek philosopher, systematically starved for 40 days. Plutarch (46 – 120 AD), the essayist, was also a supporter of vegetarianism and fasting.

Some of the famous inspiring quotes about fasting:

“Fasting is the greatest remedy – the physician within.”  – Paracelsus

“I fast for greater physical and mental efficiency” – Plato

Why the 5:2 diet?

Before choosing any diet, it is always best to explore their benefits not just for the weight loss but for the overall health. We listed here significant health benefits of the 5:2 diet.

  • It has scientific evidence that fasting for 2 days a week is more efficient than lowering calories all 7 days a week. In a recent study of 115 overweight women (age between 20-69 years), those who restricted their calories two days a week lost more fat than women doing conventional daily dieting.
  • Mark Mattson, senior investigator for the National Institute on Aging, part of the US National Institutes of Health proved the protective benefits of fasting to neurons. If you don’t eat for 10–16 hours, fatty acids called ketones will be released into the bloodstream. This process protects memory and learning functionality.
  • So it means that when choosing the 5:2 diet you not only lose weight but also protect your brain from degenerative diseases.
  • If compared to such popular diets like Paleo, Vegetarianism and other many food limited diets, the 5:2 diet makes life so much easier. You basically don’t have to search for alternatives to the food that you like.
  • Intermitting fasting has significant benefits for insulin levels.
  • Might even reverse diabetes.
  • Many busy people who work 12 hours a day on weekdays find it impossible to limit calorie intake. Therefore, when the diet is required only on 2 chosen days, it makes life less stressful.

Disadvantages of the 5:2 diet

While this diet has been shown to be effective for weight loss, there are some potential drawbacks to consider before you get started.

  • It doesn‘t encourage you to go for healthier food options.
  • You might start cheating – for example, eat more the day before a fasting day.
  • Some people report headaches when starting a fast diet.
  • It can trigger overeating.
  • It is not recommended for diabetic people.
  • To feel good during fasting days, you need to make sure that you eat 4-5 times to control your blood sugar levels.
  • It doesn’t help you to discover foods that might cause you weight gain for example intolerances that many people find they have when they go on Paleo diet.
  • You don’t actually achieve full fast effect because you eat 500-800 calories during the Fast Days too
  • It doesn’t address your eating habits that cause the weight gain.

How to choose the fast days?

It is always best to see how you feel and be honest with yourself. Is it better for you to do fasting on weekends or weekdays? Is it better to do it 2 days in a row or have 1 day between Fast days?

It is important to note that Fast Days don’t have to be consecutive. You can choose for example Sunday and Thursday as fast days. They don’t have to be Saturday and Sunday. It helps because then you can plan your holidays and occasion parties and it doesn‘t restrict you from occasionally eating out in the restaurant.

Foods that you are not allowed to eat on the 5:2 diet

You are allowed to eat all foods on 5:2 diet because the idea is just to decrease the calorie intake during the 2 days of the week.

Foods to eat on fasting days on the 5:2 diet

500 and 600 calories (and even the new rule of 800 calories) is not much.

Therefore, you need to think strategically about your choices.

The following are just suggestions, as you are allowed to eat what you want. No restrictions on dairy, grain or types of food are indicated for the 5:2 diet.

  • Eat plenty of soup. Soup is filling, and you can find low-calorie soup in cans that will save your time on busy days.  
  • Drink plenty of water.
  • Go for protein – eggs, whey protein powder. Protein keeps you full longer.
  • Try high fibre snacks like flaxseed and psyllium husk.

Best drinks for the 5:2 diet

It is best to focus on low-calorie drinks such as:

  • Water, which helps combat appetite.

It is not a myth, but a fact that is backed by research.  The study confirmed that middle-aged and older people who had two cups of water before eating a meal consumed between 75 and 90 fewer calories. If you use this method 5 times a day, you can save 360kcal already. The impact of water intake on weight status has also been confirmed, when the water replaced sugary and energy drinks.

Use it during non-fasting days too to benefit.

  • Coffee with stevia (no milk or cream).
  • Soup. For example, broth-based vegetable soup or miso soup.
  • Alcohol is not recommended. Alcohol is very high in calories. A pint of lager contains the same amount (197) of calories as a slice of pizza. Do not waste calories on the drink. Better have a healthy salad.

Snacks for your Fast Diet fast days

Snacks are dangerous for any diet as we forget that it should be just a snack between 50-100 kcal, not another meal. When your total daily calories are only 500, it is best to allocate 50 calories for your snack. Is it possible?

Yes! Here you have good examples of what you can include in your meal plan of the 2 fasting days.

  • Sliced apple with 1 tbsp of almond butter
  • Miso soup 36 calories
  • Small celery stalk smeared with 1⁄2 Tbsp natural peanut butter (49 calories)
  • 1 tsp almond butter (34 calories)
  • 2 marshmallows: 46 calories
  • Hartley’s Sugar-Free Jelly: 10 calories
  • Weight Watchers Fromage Frais: 49 calories
  • 1 cup air-popped corn: 31 calories
  • 1 plum: 30 calories
  • 2 Light Cheese Triangles: 50 calories
  • Options Belgian Hot Chocolate: 40 calories
  • 100g watermelon: 30 calories
  • Half small banana: 45 calories

What to snack on when you want to block appetite and feel full longer? We have excellent advice for you. There are 2 high fibre foods that are widely used to prevent hunger and also for their vast health benefits.

10g psyllium husk (40 calories)

First of all, psyllium husk improves glycemic control. Secondly, it provides a natural constipation relief. Thirdly, it reduces cholesterol. It is important to note that based on the study the effect significantly increased in time. So you should consume psyllium husk for more than 8 weeks. 

Finally, if you focus on the weight reduction, psyllium husk has been confirmed to help with weight loss. A study published in Clinical and Experimental Hypertension in  2007 discovered that psyllium supplementation for a six-month period led to a decrease in body mass index. It is best to consume it before a meal to reap its benefits.

1 tbsp of ground flaxseed (37 calories)

Why flaxseed? Flaxseed is an excellent diet food for weight loss, as it also reduces inflammation.

Include the above 2 instead of others and see if they help you survive through the fast days.

Sample menu for the 5:2 diet for fasting days

Here is a 500 calories menu that will help you plan your first week of the 5:2 diet:

  • 125 calorie breakfast:  1 large boiled egg (80 calories)  + and 28g green olives (41 calories) and a cup of coffee (no sugar, no milk) (4 calories)
  • 50 calorie snack:  2 Light Cheese Triangles
  • 195 calorie lunch:  Smoothie: whey protein scoop in water (110 calories) with a bowl of blueberries (85 calories).
  • 130 calorie dinner:  1 roasted skinless chicken drumstick (75 calories) + small baked sweet potato (55kcal)

Do not forget to drink 2 litres of water throughout the day. You can always go for the relaxed version of diet and 300 calories.  Moreover, there is an excellent opportunity for you try tasty recipes during your fasting days.

Additional tasty recipes

(warning: read what is counted as 1 serving)

Under 200 calories breakfast

  1. Buttermilk buckwheat pancakes recipe
  2. Maple sausage patties recipe
  3. Avocado breakfast toast
  4. Strawberry + Banana Chocolate Chip Oat Muffins
  5. Yogurt Chia Seed Pudding
  6. Frozen Yogurt Bark with Pomegranate & Dark Chocolate
  7. Banana Matcha Energy Bites
  8. Vegan Double Chocolate Protein Fudge

Under 200 calories meals

  1. Oriental steamed fish
  2. Aubergine rolls
  3. Red lentil curry
  4. Homemade Black Bean Veggie Burgers
  5. Yummy Honey Chicken Kabobs
  6. Asian Beef Skewers

Each person is different, so you need to decide if you prefer more filling breakfast or lunch or dinner and you can create a list of recipes that are 100, 150 and 200 calories and create menus for 4-5 meals/day including 50kcal snack for your next fasting days.

For example, if I know that I feel much better all day when I eat the most substantial meal for breakfast (and also I always need a snack at 3 p.m.) , then my daily menu would look like this:

  • 225 kcal breakfast:  2 large eggs + 10g olives + half of small banana + cup of coffee
  • 120 kcal lunch: strawberry whey protein scoop in water
  • 36 kcal snack at 3 p.m.: 1 cup miso soup
  • 119 kcal dinner: 1 roasted skinless chicken drumstick (75 calories) and celery stalks (44 calories).

Before throwing yourself on a diet, monitor yourself during a week. See what works better for you- bigger lunch or bigger breakfast, timing, types of food and then create your best personal meal plan. Self-awareness is your best friend in this journey.

Shopping list for the 5:2 diet

Print out this shopping list which will help you focus on the low-calorie food and survive the 2 fasting days. Here you will find low-calorie foods and high fibre items to keep you full for longer.

Fruits and Vegetable

  • Celery
  • Cucumber
  • Lettuce
  • Asparagus
  • Beetroot
  • Spinach
  • Blueberries
  • Olives

Dairy and eggs

  • Large Eggs
  • Feta cheese
  • Low-fat low sugar yogurt


  • Whey protein
  • Tuna can in water
  • Almond butter
  • Ground Flaxseed
  • Psyllium Husk

Noodles, pasta and grains and soups

  • Kelp noodles
  • Soup can with lowest calories. For example, a can of minestrone soup, which is more filling than chicken broth, can be only 200 kcal.
  • Miso soup packs


  • Stevia


  • Coffee
  • Redbush tea
  • Spring water

What to order in the restaurant

Restaurants can be tricky when fasting.  As mentioned before – you should plan fasting days ahead so that those days don‘t collide with holidays when you promise to meet with your friends and family.

It can be tough to see everybody snacking and eating amazing dishes in the restaurant or café around you while you have 50 calories left to consume.

Some ideas of what to order under 350 calories (of course if you still have that number saved):

  • Starbucks: Spinach, Egg White and Feta Wrap 290 calories
  • Pizza Express:  Primo Gelato banoffee  243 calories
  • Whetherspoons: salted caramel cheesecake at 347 calories.
  • Pizza Hut: Hawaiian on an Italian base 160 calories per slice.
  • Burger King: Grilled Chicken Caesar Wrap 343 calories
  • Nando’s: Peri-peri Chicken Fillet Pitta 347

Low calorie fats food exists too. For example:

  • Taco Bell Fresco Chicken Soft Taco  just 150kcal
  • Fresco Grilled Steak Soft Taco  150 kcal
  • McDonald’s Chicken McNuggets – 4 piece is 190 kcal

The 5:2 diet has become popular because it has scientific evidence behind it and is not so psychologically stressful as diets that require every day planning or finding alternatives of the most consumed foods and relates to the long known fasting traditions.

Therefore, if you are considering to try a diet for health benefits as well as weight loss, this one might help you to stay focused on your goal for longer as you can enjoy your relaxed breaks with your favourite food.

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