How does that saying go? Ask 10 forum members for advice and you will get 11 opinions on what is best. The concept of 5:2 by Michael Mosley comes largely from the work of Valter Longo a researcher that looks into longevity and fasting. There was no scientific basis for choosing 500 cal for your fast days. It was a number plucked out of thin air and it was what Mosley though most people could actually do. If you can do zero cal on your fast day, great. I do zero on my fast days. I have been in maintenance for 3 1/2 years now and do 6:1.

If you eat whatever you want can you still be successful? Yes but the odds will be stacked against you. Some people can probably get away with it, I suspect most will not. Just go to the maintenance section and ask those that have been maintaining for a long time whether they eat anything they like, or whether they are disciplined and eat healthy most of the time.

So here is my take on things. If you choose to eat healthy foods then there is no need to count calories. I have never counted calories. What do I consider healthy? I have eliminated all processed grain based foods. I consider them to be pure junk food. No bread, pasta, pizza, biscuits, rice etc. No added sugar. No fruit juice, pure junk. What do I eat? Mostly vegetables, some fruit, some meat. Lots of legumes, beans, lots of nuts and seeds. Pretty basic really. Do I have treats? Yes but its a rarity. If you eat healthy your chances of success are high. Eat crap and you greatly diminish your chances of success.

If you feel that the fasting side of things will be easy for you then by all means whats stopping you from starting? Go for it. If you also combine it with healthy eating there will be no need to count calories. Good luck.

Hi MrsP,

There are people who eat many various ways for various reasons – individual versions of what people consider healthy, philosophical, medical, religious, national, and sometimes just fads, but, you get to choose what you want to eat, what fits your goals, your health, age, life factors, medical situation etc.

The constant is ‘sugar is bad for you’, so most here eventually end up using little of it over time, and relax a little at special celebrations.

At first people think fasting is very difficult. It usually takes 1-3 weeks for people to realise it’s not hard if you know what to do, and just about everyone finds it easy after those first few fasts. Most of us actually look forward to our fasting days.

The 500 cals was a bit arbitary but it was what Dr Mosely thought people could handle and still get the fasting benefit. It works. You will need to work out your TDEE – Total Daily Energy Expenditure for your non-Fast Days. Fasting days are up to 500 ( or 800 in the new version) or up to 1/4 of your TDEE. You don’t multiply the 500 for your nonFDs. Eg. My TDEE is quite low because of my personal situation at 1440. So on FDs I do 360 and occasionally 500. You’ll probably need to calorie count for a short time only while you get used to what works for you.

It is not at all like calorie counting for everyday of deprivation which other diets do. This is a healthy way of life where you get to eat what you want to. It does say you can eat what you like, but it doesn’t say eat ‘as much’ as you like.

I’ve been on 5:2 for 3yrs 9months, despite being unable to exercise for health reasons. I lost 21kgs and learnt what fits my lifestyle, and I’ll keep doing it now because it’s a joy to know I’m a normal weight, that has improved my health as much as it can, and I’m more than happy.

Mrs P. Join a thread with large numbers of posts that feels a comfortable fit for you. You’ll get support and questions snswered. You will gradually work out what works for you.

One thing I wouldn’t do, MrsP, is eat 2000 calories on a Slow Day. If you don’t want to count calories [as an old ‘counter’ myself, I don’t find that difficult, but to each his/her own], at least cut down on foods of scant nutritional value on Slow Days. I still eat cookies and ice cream and go out for dinner, but not all the time. My TDEE =1450 which is sufficient for me after 5 years of Fasting 2 days/week. We still Fast because we enjoy the foods we eat on Fast Days and because it keeps our weight down.

Dear MrsP, I am sorry that I affronted you. It was not my intent.
I questioned your TDEE not to imply that you were very overweight, but to help you to lose your weight.
Using the numbers, you provided, I calculated your TDEE under Resources on this page at the top.
When you put in your current weight , 13 stone, the TDEE = 2026 calories.
But that is your current weight, not the weight you want to be. If you plug in 12 stone, TDEE = 1939 calories. For 11 stone, TDEE= 1852 calories per day. Do you see why I was confused and inquired about your TDEE? Try it with a setting of 10 stone [since you want to lose 3 stone] and see what you get.
I wish you the best of luck.

@dykask. Digressing a little, modern agriculture has done us a great disservice. By making most foods more calorie dense we have gone down a very poor path. Granted it has help feed those in third worlds but for the rest of us it has been a very poor outcome. The fruit and veggies we now eat bare little resemblance to what they did 100 years ago. The sugar content has gone up and the fibre content has gone down. Last year while on holidays in Darwin (northern Australia) I asked an aboriginal if it was OK to eat an “apple” I had found while hiking through a national park. Yeah sure, its a bush apple. It was small, nearly all fibre and a hint of sweet pear taste. So different to the sugar laden apples we now have.

Pick nutritionally dense foods with lots of fibre content. Do that and its hard to go wrong. Think long and hard before choosing processed foods.