Some insights on the 5:2 diet

Thierry Clerc, Clinical Homeopath, Nutritionist, Bioresonance practitioner, Cambridge (UK)


I have been practicing nutrition for more than 9 years now, and I have helped countless clients achieving optimal weight with a normal diet. Since early 2013, the 5-2 diet has become very popular. I do not suggest it, however several of my clients have decided to try it alongside my holistic support for their other ailments.

I have seen some success with it, but also people having severe issues on this, especially people with high sugar-intolerance or a congested digestive system. For this reason, I wrote this short article to help my client who have decided to go on this programme alongside my current support.

5-2 Diet Outline

This is a calorie-counting approach. You are supposed to reduce calorie-intakes for 2 days and eat whatever you want for the 5 other days of the week. This is why it is called 5:2. If you decide to reduce calories for 1 day a week, it is a 6:1 and if you do it for 3 days a week, then it is a 4:3.

The days when you reduce your calorie intakes are called “fasting”, even if it is not a real fast.

The theory behind it is that it will force your body to use your un-used fat.

This is backed by scientific evidence in the short term, when people with chronic conditions have been supervised and lost weight over several months. The other benefits showed by the study was a reduction of the symptoms in the chronic conditions (primarily diabetes, hypertension) and that the people did not feel hungry while fasting.

Personal Views and Experience on the 5:2 Diet

The 5:2 diet is a calorie-counting exercise. While fasting is an important part of many cultures, it is usually down over 2 weeks to 5 weeks a year in most traditional cultures, and would focus on the food to eat, instead of calories.

I had several clients who did very well on the 5:2 diet and for this reason, if people are drawn to this diet, I will support and encourage them while they are on this programme.

However, in my view, the metabolic balance programme is far more superior as it does not bother about calories and instead re-teach people on how to eat accordingly to their genes.

When people have lost weight on the 5:2 diet, the question is to stay on it or not. There are not enough long-term scientific studies to back a long-term 5:2 or 6:1 diet and in my view, this approach can lead to some health issues: reducing calories usually means reducing good quality fat or nutritious ingredients, and the diet can still be very bad for the rest of the week.

Feel free to contact me and book for a review of your health state and nutritional plans.


How to know your calorie intake for your “fasting days”

The 5:2 diet suggests to have 1/4 of your normal calorie intake on fasting days.

1/4 was used for the main medical study, and this ratio could have been different.

First calculate your Basal Metabolic Rate, also called “your resting caloric intake”. Tis is the amount of calories, that you need to have only for your basic functions. The theorical calculations is:

Male BMR = 10 * weight (kg) + 6.25 height (cm) – 5 * age (years) + 5

Female BMR = 10 * weight (kg) + 6.25 height (cm) – 5 * age (years) – 161.

You can find useful online calculators. I also have a machine that allows to calculate this.


To now your theoretical calorie intake, do as follows:

  Theoretical daily calorie need
Little / No exercise BMR * 1.2
Light exercise BMR * 1.375
Moderate exercise (3-5 days a week) BMR * 1.55
Very active exercise (6-7 days a week) BMR * 1.725
Extra active (physical job and very active) BMR * 1.9


You just then need to divide a 1/4 of your Theoretical daily calorie need


Tips for the 5:2 Diet

The 5:2 diet is a calorie-counting exercise. To know how many calories, you take, you need to measure the food and refer to a table. is a very good site to help you on this.


Then, count the amount of calories for your day, here is an example:




























My advice are:

– try and have 3 meals a day, no more, no less.

If you are congested and not hungry, and feel having only one meal a day, it is usually because your metabolism is not right, and this should be sorted first.

If you feel grazing all day, then you probably are very sensitive to blood sugar levels and insulin levels. And this also need to be sorted first.

– do not take any sugar or alcohol, as this will make you hungry

– drink plenty of water between meals.


Good luck and let me know how you do.






Thierry Clerc, MARH, RHom, MSc
Registered Health Practitioner
Clinical Homeopath, Metabolic Balance Practitioner & Nutritionist in Cambridge


Some insights on the 5:2 diet
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