The 2-Day Diet

2 Day Diet Healthy Eating Prevent Breast Cancer Charity UK

The 2-Day Diet is a clinically proven and easy-to-follow intermittent diet that can help you lose weight and become healthier. Developed by acclaimed Prevent Breast Cancer scientists, Dr Michelle Harvie and Professor Tony Howell, it is a revolutionary approach to weight loss which calls for just two days a week of dieting (restricted days), rather than counting calories or skipping meals.

Unlike other 5:2 diets, there are only a few simple rules to follow on the diet days – low in carbohydrates (including low-carb fruit and vegetables) but high in protein and healthy fats. This means that the two ‘restricted’ days will leave dieters feeling full and satisfied, rather than battling cravings. It is suggested to do your two days of dieting together. For the rest of the week, a balanced Mediterranean-style diet should be followed (more on this later).

To reap the full benefits of the diet, on the ‘unrestricted’ days you should still be eating healthily, but you won’t have to drastically cut your calories or feel as if you’re depriving yourself of food as you would on other diets.

What you can and can’t eat and drink on your restrictive days

It is important to drink plenty on your ‘restricted days’ –  we recommend you drink at least 8 glasses of fluid each day . This helps you to feel full and helps prevent constipation.

Your 8 drinks can include –

  • Water
  • Tea
  • Coffee
  • Green Tea
  • Herbal Teas
  • Sugar-free, no added sugar or diet squash and fizzy drinks

We often mistake thirst for hunger, and so if you really fancy something to eat, try having a large drink first and see if your cravings go away. There’s no need to avoid drinks containing caffeine, for example tea and coffee. Some research shows these drinks can be beneficial for your health.

Food and drinks to avoid on restrictive days


  • Bread, or food containing bread such as breaded fish
  • Breakfast cereals including porridge oats
  • Pasta, or pasta products such as lasagne, spaghetti in tomato sauce & ravioli
  • Rice, or rice products such as risotto, rice pudding & sushi
  • Potatoes, or potato products such as fish cakes, mashed potato, chips & waffles
  • Crackers, crisp breads and rice cakes
  • Sugar and foods with added sugar: e.g. cakes biscuits, fizzy drinks, honey, sweets & chocolate (you can use sweeteners)
  • Flour or foods containing flour such as white sauces


  • Alcohol
  • Adding sugar to drinks
  • Regular fizzy drinks which contain sugar
  • Fruit juice or shop bought smoothies
  • Drinking chocolate (can have cocoa sweetened with sweetener)
  • Malted milk drinks (e.g. Horlicks, Ovaltine) including low fat versions
  • Flavoured water which contains sugar (check the label)

Tips for your unrestricted days

As above, it is recommended to follow a balanced Mediterranean-style diet on your unrestricted days, this includes wholegrains, nuts, oily fish and plenty of colourful fruits and vegetables, plus the use of healthy fats like olive oil.

Carbohydrate foods give us energy and are often accused of making people gain weight. This is quite unfair – by themselves carbohydrate foods are quite low in calories, but we tend to make them higher by adding fat to them, for example by spreading butter thickly on toast.

You should choose wholegrain carbohydrates whenever possible. These have more fibre and nutrients than white versions and they help keep your bowels healthy and limit constipation.

Try to cut down on sugar and sugary snacks such as sweets, cakes and biscuits. These give us extra calories with few nutrients and because they are quickly digested, they often leave us craving more! White refined carbohydrates and sugary foods make the body produce more insulin which can increase the risk of developing cancer, heart disease, diabetes, and dementia.

Why the need for the diet?

Being overweight and gaining weight over adult life can increase the risk of developing breast cancer. The average woman in the UK gains a stone in weight over their adult life. This increases risk of breast cancer by about 20% whilst gaining 1 and ½ stone increases risk by 60% and 3 stone doubles risk.

If you are someone who has already gained weight, you will be interested to know that weight loss seems to help reduce this extra risk. Prevent Breast Cancer was one of the first research groups to find that weight loss can reduce the risk of breast cancer. In our study of 34,000 women modest weight loss i.e. losing 10 pounds of weight reduced risk by 25-40%.

Benefits of the diet after breast cancer diagnosis and treatment

Many people with breast cancer have problems with their weight. For some, these can be long-standing problems, or they may be because of weight gained during treatment. Typically, three out of four women with breast cancer put on weight during treatment, including those who were previously a healthy weight. This happens with many different cancer treatments, as people can become less active and may find themselves eating more as their routine has changed or they could be comfort eating and have an increased appetite.

Being a healthy weight and doing regular exercise can increase your sense of well-being, boost energy levels and improve your mood. There is some evidence that it may also decrease the risk of cancer recurrence because it lowers levels of cancer promoting hormones. It may also reduce the risk of other health problems such as heart disease, stroke, dementia, diabetes and osteoporosis.

Other benefits of the diet

Giving up smoking

Once you’ve sorted out your diet, you hopefully will be inclined to become healthier in other parts of your life, including giving up smoking.

We all know that smoking is bad for our health, for our hearts and bones and makes us more likely to develop cancer.

For many people quitting is not easy; however, lots of help is available through the internet, free telephone helplines, pharmacies and your GP or practice nurse.

Many people put on weight when they quit smoking. To avoid weight gain, take care not to replace the cigarettes with high calorie snack food. It will also help if you increase the amount of physical activity you are doing. Exercise can help to take your mind off the cravings!

NHS Stop Smoking Advice:

Call: 0300 123 1044 – Monday to Friday 9am to 8pm and Saturday and Sunday 11am to 4pm.

Or visit;

Healthy Bones

Our bones get thinner and our risk of Osteoporosis increases as we get older, after the menopause and because of certain breast cancer treatments including Letrozole (Femara), Anastrozole (Arimidex) and Exemestane (Aromasin).

Good bone health comes from having a healthy diet with plenty of calcium and Vitamin D, combined with regular weight bearing exercise like walking and enough daily exposure to the sun because our bodies make Vitamin D in reaction to sunlight.

For healthy bones try to:

  • Eat calcium rich foods: low-fat dairy, fish with bones, green leafy veg, pulses, beans, nuts and seeds and dried fruit to achieve 800mg per day
  • Eat Vitamin D rich foods: oily fish like trout, mackerel or salmon, liver, eggs, cod liver oil and fortified breakfast cereals
  • Eat plenty of fruit & vegetables
  • Limit alcohol and salt
  • Limit caffeine intake. Aim for no more than 3 cups of coffee a day or 10 cups of tea.
  • Limit energy and cola drinks to 3 cans a week.
  • Don’t smoke
  • Take regular weight bearing exercise
  • Daily exposure of skin (without SPF sun cream) for 10-20 minutes per day, combined with a diet that includes Vitamin D rich foods should provide enough Vitamin D for healthy bones. Avoid allowing your skin to redden or burn in the sun.
  • If you’re not getting enough Vitamin D from your diet the Scientific Advisory Committee on Nutrition suggests taking a Vitamin D supplement and we recommend choosing one with 10μg (sometimes written as 400IU)

Your doctor may ask you to take a combined calcium and vitamin D supplement to help keep you bones healthy.

What next?

Thinking The 2-Day Diet is something you want to get on board with? Then how about purchasing one of the official books written by Dr Michelle Harvie and Professor Tony Howell to get you started.  What’s even better is that all proceeds are donated to Prevent Breast Cancer.

We even have our own online support group for those following diet and who want some extra motivation, simplified recipes, tips, tricks and comradery. Find the private group by searching The 2 Day Diet Club on Facebook or clicking here.

Some members have even combined a weight loss goal and are donating one pound for each pound of weight they lose!

So, say hello to the new you! Lose weight and feel great!