I have got out of the habit of eating after 14:00, and I have to eat to keep up to my target weight! (no sympathy expected)
I have been Intermittent Fasting (IF) 20/4 for over 18 months, and fasting for 68 hours most months - but I missed last month, partly because I was below my target weight (95kg, 14% body fat).
So I "ate plenty" over Christmas: (Do calories matter if you record what you eat?)
On Christmas day I ate my normal 1459 calorie breakfast:
healthunlocked.com/nhsweigh...
Some community locals put on a party for about 100 of us that would have been alone at Christmas:
I had two large mince pies and chocolate biscuits with my coffee @ 11:00.
Bread roll with butter
Turkey and all the trimmings
A second helping of "pigs in blankets"
Profiteroles and cream
Christmas pudding and cream
more mince pies
two plates of biscuits and cheese.
They gave us all presents - but I gave away the large box of shortbread they gave me.
I have eaten nothing since.
20 hours later I was a kilo over my target weight, and I walked 8 kilometres. When you are fasting, once you have used up your glycogen energy store, you can only exercise at the rate at which you can get energy from your fat stores - so gentle, aerobic exercise is best. (Hunter-gatherers are so well fat-adapted that they can hunt, and run down antelope, having not eaten for a week or more!)
44 hours into the fast I was back to my target weight - and I will go for another walk.
68 hours into my fast (Saturday) I will break my fast (with full-fat yoghurt), as my son is meeting me for lunch.
If any of us were trapped or marooned, and could not eat for a few days, few of us would come to any harm, and Dr Jason Fung puts many of his acute diabetes on an initial medically-supervised two or three week fast.
...but, if you do not have acute diabetes, cancer or another non-communicable disease, are not at risk of losing life or limb, then it is best to transition into the Low-Carbohydrate, High-Fat (LCHF) diet and Intermittent Fasting (IF) over a few weeks, see:
healthunlocked.com/fasting-...