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5:2 Diet 'Rules' & Variations

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Dear forum members I'm seeking your guidance & experiences please!
I am thinking of trying 4:3ing throughout January to try to boost my weight loss & by coincidence I noticed The Saturday Times is promoting 4:3! But I seem to remember that in previous forum stats 4:3ers didn't seem to lose much more than 5:2ers? Would you recommend it & I am assuming you eat to your TDEE on eating inbetween days with possibly way hey weekends?

The numbers show doing 4:3 will cause about an additional 7 oz. of weight loss per week. 5-2-diet-chat-f6/topic6600.html

You have to decide if it is worth it for you.

Good Luck!
Thank you for the link simcoeluv. I am such a slow loser it might be worth it for a month.
You will find some info on this in the results from our questionnaire, here:
I am an incredibly slow loser, steady but slow. May be because I refuse to count calories, but hey ho.
I switched to 4:3 and while I can't say it's speeded things up it has been steady at about 2lbs a month. (I only weigh monthly)
However, it is easy, there is a rhythm to it that suits me and if my Thursday fasts are tough/not going too well I don't feel too bad if I have a bit more to eat. Although that only happened relatively recently. At that point I did consider going back to 5:2.
Now, after a holiday and Christmas I am ready to get back into the 4:3 groove.
I think it's worth a try. If it's to boost weigt ht loss then the strictness applied to 5:2 is still needed otherwise it may not do what you want it to.
Do let us know what you decide and how it goes.
In theory, of course an extra fast day should speed up weight loss, but there are some facts that might counteract the reduction in calories on the extra day. These are a tendency not to stick to TDEE on non fast days as a reward for doing an extra day (probably unlikely due to the appetite suppressing effect), and/or increased cortisol production due to the stress of fasting.

Why not give it a go?
Hi, I'm glad you've asked this question as I've also been toying with the idea of trying 4:3 for a short while.
I was interested to read the summary of the recent questionnaire analysis.

The results of a questionnaire sent out to members of the 5:2fastdiet forum were analysed statistically to try to discover what are the main factors influencing weight loss with this diet and how great an influence each factor has. As is the case with all diets, gender, starting BMI and duration of time on the diet were, unsurprisingly, key factors influencing the speed of weight loss. Overall, a quarter of the variation in speed of weight loss is accounted for by these three factors. As few men answered the questionnaire and some factors appear to have a different effect for men and women, our full analysis had to be restricted to only the women participants. While physical activity might be expected to enhance weight loss, we were unable to show this in our analysis. This is likely due to insufficient data about change in activity levels before and after starting 5:2. An important factor influencing weight loss is the number of hours with no calorie intake on fast days. Fasting fully (no calories) for more than 20 hours on fast days increased weight loss by around 120 grams per week compared with a 12 to 16 hour fast. Only a few people fast for less than 12 hours or longer than 24 hours but the difference between these extremes in terms of weight loss appears to be even larger at 240 grams per week. Adding an extra fast per week (i.e., 4:3 rather than 5:2) seems to result in faster weight loss, but the participants using 4:3 were too few for this effect to show in the full analysis. Although the main calorie restriction is conferred by the 2 days’ fasting, participants’ eating behaviour on the non-fast days had an important effect on the speed of weight loss. Firstly, bingeing on feed days can, unsurprisingly, slow down the weight loss. Compared with women who never binge, those who binge sometimes or often experience slower weight loss: in the order of 120 grams per week. Bearing in mind that the average weight lost per week for the women in our study was 490 grams per week, an effect size of 120 grams is important. Secondly, a change in dietary habits to a ‘healthier’ diet (defined as eating fewer snacks, less sugary food, fewer ready meals and eating more vegetables) appeared to increase weight loss by around 250 grams per week. Roughly one half of this effect is estimated to be the result of a change in food content, the other half is estimated to be due to eating less food (change in food quantity). Our final analysis, which takes into consideration the five main factors (BMI, weeks on diet, binge behaviour, healthy diet and length of fast) was able to explain almost half (40%) of the differences in rate of weight loss seen in the women who answered our questionnaire.
I did 4:3 for the majority of the year and lost the same as the average 5:2 person but I'm not a calorie counter...

I liked it as it was regular and organised but it's not necessarily faster, imo.
:heart: Hi @isis Why not give it a month to see how it goes for you as you know I've done 4:3 from my start and that has led me to doing 16:8 most other days I firmly believe this combination is the reason for my phenomenal success :heart:
@Isis, there is always someone who likes to contradict everyone else :wink: .

This is just my experience. I used 4:3 in July/August to get me off a plateau - it worked, I lost 6lbs in about 6 weeks. But...I found it really hard going. I just felt it was one step too far to being on a diet. The only thing is I went back to 5:2 afterwards and I haven't lost any weight since. I am happy doing 5:2 but 4:3 isn't for me.

I'd say give it a go, we are all different.
I prefer 4:3. I find fasting easier without long breaks between fasts. Other than occasional scheduling difficulties and the third fast day being tough going in the beginning, I had no problems with it.
Hi @isis, I have been throwing in the odd extra fast per week for about the last 3-4 weeks, and I think it did get me off a small plateau. And like MaryAnn, I don't like having too many feed days in a row, I like to stay a little bit closer to my fast days. I don't find it any harder than 5/2, some fast days are easier and some harder anyway, and I like to mix it up a bit regarding which days I fast. So if I have the opportunity I'll wake up in the morning, like today, and just do it.

Good luck!
Hi Isis, I am experimenting with alternate day fasting at the moment which isn't that far removed. I am able to as I am working away for three weeks a month and the food temptations aren't there! I figure that I can't compensate for my fast days as I would have to eat far more than I am capable of. I fasted yesterday and so far haven't felt like breakfast.
Where in West Sussex are you? I grew up in Steyning!
Debs I live just outside Horsham so not that far from Steyning. How are you enjoying living in Tasmania?
A big thank you to you all for your experiences & advice I really appreciate your help. I think I will add an extra fast day on Wednesday for a couple of weeks to see how I feel :smile:
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