Hi there,

Welcome!

Yes, I read the book and was uncertain as to what to do as well. He says eat normally. I have also heard to eat at your TDEE or at your Total Daily Energy Expeniture. Here is a calculator for that.

https://tdeecalculator.net/

I read a lot about it and I read that basically the fewer calories you eat on your Non Light Days, the faster you could lose. So, for me I have been counting calories and exercising. I end up eating around 1350 or so on and I have been exercising six days a week. This has been working well for me. I am down around 40 pounds since starting in late March. My two Light Days are Mondays and Thursdays and my day off from exercise is on Fridays.

Everybody needs to do what works best for them, and what fits their lifestyle. Note that I will also add in a cheat meal on Friday and Saturday nights. So by restricting a little more during the week it makes me feel a little less guilty about having those cheat meals.

Hope that helps!

I ate at maintenance levels on my 5 days using the MFP eat back exercise calories method which I personally prefer to the average TDEE method although it's 6 of one and half a dozen of the other if done properly.
(No eating back exercise calories on the two fasting days though of course.)


And this is 100% wrong!

I was planning to try stick to my BMR on non-fast days.

BMR is not your maintenance level - that's the level if you were at total rest for the entire 24hrs.
Think you are confusing BMR with TDEE?

I just laugh when Dr. Mosely says to just eat normally on non-fast days. What?? If I could eat normally I wouldn't need 5:2.

What I am doing is setting my calorie level at what it would be to maintain my initial goal weight and use that for my non-fast days. If you google something like "how many calories do I need to maintain my weight" you will find plenty of calculators. I do log my food with MFP on the non-fast days because left to my own devices my non-fast days would get out of control. I also try to exercise every day even if that is just a walk. I don't eat my exercise calories back because I want to get used to eating for my goal weight. So far it is going slow but steady and I am good with that.

My one piece of advice is not to go too low on calories on your non-fast days or your body will think you are in a famine and start to conserve for self-survival purposes. I am sure you will figure out the calories for yourself as you go along.

Welcome to 5:2 @Busymissbridge! Feel free to post if you have any more questions. We are a friendly bunch.