Yes, all are very complicated. I went done the rabbit hole on each at one point or another. And made decisions that fit my understanding, a goal of long term health, and allows me to produce some of my own food.

1. protein--need an adequate amount. More at the initializing LC after falling off the wagon, and fats too. Eating high quality grass fed organic meats are worth eating even if it means eating smaller portions. When a duck gets invited to dinner, we use up the meat asap, eating more than usual. Processed ducks go into the freezer.

2.Vegetables--what kind and how much. Dr Atkins fits my opinion. Eat as much as your body will allow. Potatoes are out in favor of fresh green beans and tomatoes from the garden. The potatoes we produce, my skinny teen eat. And some go to the dogs. We are building our gardening skills: on the number of varieties. Last fall bok choi thrived on neglect, loves the cool weather, and I harvested well into the fall. 3 eggplants picked today-- the first ever for my efforts!!! Planted an orchard, goal is organic, and no pesticides at all, or at least not conventional, peaches, pears, apples, cherries. I highly recommend the dwarf cherries, which are bushes up to 6 feet. These are low glycemic fruits. Beets have beneficial properties that are unique. As does celery and cukes. Mushrooms!! Lay stem removed mushrooms out in sun for 6 hours and boost the vit D content-- according to one website. Then store the dried mushrooms, eating only a few at a time. Also we dry fruit for my kids lunches-- a cheap candy and better nutrients for my teens. Jicima is delightful. Like a more fibrous apple. I could add so much more--

3. Fasting-- I looked at Phinneys information carefully, and felt he was genuinely concerned given the clear data; Dr Fung seems rather gung-ho to the point of closed ears and clearly stated he is only interested in weight loss not on good health. I love his enthusiasm, and have watched many of his YouTube postings, and think he is a breath of fresh air, but on this I think short term fasting is enough. For me 24/1 is my maximum because, honestly, I love cooking and I love eating good foods. Historically many groups of people, usually for religious reasons, fasted regularly, but it was short IF types. Not days at a time. I would like to keep my metabolism UP as I continue to age, and fight to keep muscle mass, and keep very active as my grandfather did living well into his 90's, living independently, helping others, and still keeping house, albeit a smaller house. Otherwise, it is good to know that if a famine hits, I know we can survive.