I was under the impression that stored glycogen was consumed after about 12 hours. Youre saying ketosis comes in after 3 days. So what is the majority calorific source that you are consuming from the 12 hour mark to 72 hour mark? If its not glycogen and its not fat that only leaves (muscle) protein. I find it hard to believe that the body opts for protein as its major food source for 2 1/2 days rather than stored fats?

Someone is going to have to come up with the science facts on this one.

My understanding is that when fasting ketosis doesn’t “fully” kick in until all stores of glucose/glycogen are depleted in 48/72 hours, this can be quickened by eating a high protein diet for a day or two before beginning a fast. (Ketosis onset is a gradual process, not lighting off a bottle rocket.)

Now that’s my understanding and is one reason I do 4-5 day fasts once a month.

Someone point me to a scientific time line on this one please.

How long it takes to get into ketosis is not a fixed amount of time as it depends on several factors. What is important that you are losing weight.
If you are not doing so already you could limit your eating window on non fast days for example only eating between noon and 8pm. A small study has shown that it helps in losing body fat without restricting calories.

Someone posted this on another thread

http://www.bbc.co.uk/programmes/articles/zBx3JZJCKfNBrWgT0Qyj93/the-big-experiment-could-i-lose-fat-just-by-changing-my-meal-times

Thanks atcgirl – yes, I try to stick to 600-700 cals per day. Late morning I make a whey protein shake/smoothie with 50 ml milk and 6 strawberries (as they are low carb) = approx 150 cals. Early afternoon I have two hard boiled eggs on a green salad = approx 150 cals, then dinner is 80g of cooked skinless chicken with green veg (no starchy veg) = approx 150 cals. I also love my coffee with milk – I have about 4-5 with skim milk = 120 cals. If hungry at night, I have a low cal vanilla yogurt tub (no fruit) = 70 cals. By day 2, ketosis kicks in, and it’s fairly easy going.

A lot of good answers here in relation to ketosis.

I just came back here after joining a very strict ketogenic site (ruled.me …felt almost like a cult!) , and I now think some people take it too far measuring ketones and blood glucose and constantly worrying about it.

Personally, and it may not work for everyone, I started low carb/ slightly high fat at the same time I started 5:2, then 4:3. When I need to lose more, since I am almost to my ultimate goal, I do a 3-4 day liquid fast. On non-fast days, I don’t snack, don’t cheat, do HIIT on fast days, weights on NF days.

Listen to your body, look in the mirror, decide how you feel. The first few days going into ketosis feel like crap (keto flu), but as soon as your body adjusts, you feel great. Your weight starts dropping.

Each person has to experiment to find their dietary “sweet spot”.

And simcoeluv, awesome post!

Hi fit:

Thanks!

I agree with you that some take worrying about ketosis and fat burning too seriously.

The less you eat, the more you lose!

I agree atcgirl. I have been SO frustrated some days (over the past 2 years) when I have strictly stuck to 500 cals on a fast day, and not lost a single gram of fat on the scales the next morning (lots of reasons for that obviously). So your first post in the forum really resonated with me! But reading more ‘science’ about what to eat and do on the 2 fast days has really helped me refine my diet, boost the weight loss and keep me more motivated. So now, if I put on a couple of kilos over Xmas, I know I can drop them off in a couple of weeks, and not a couple of months. Good luck with your 5:2 journey! 🙂

Has anyone else noticed that they run slightly “hot” when they have reached ketosis? Definitely by the second day if I touch my stomach Im running hotter than usual. From what Ive read not everyone experiences this. Anyone else experience this? At least its easy for me to sense when Ive hit ketosis.