I am currently "researching", learning all this stuff. So I guess take it with lots of caution?
Since you asked, this is headlines of most of what I figured out:
* Your main goals should be achieving metabolic flexibility, eliminating most of the "bad" stuff (sugars, processed oils, most carbs, etc.), supplying your body with mitochondrial decouplers daily and doing low level aerobic exercise, consistently.
* If you feel hungry at any time you are doing something wrong.
* If you feel cold due to lower basal metabolic rate at any time you are doing something wrong (most likely restricting calories in an improper way).
* Metabolic flexibility means you can can easily get into and out of fasting. You are not driven by hunger and can easily continue your life (work, exercise, etc.) with or without meals, without detriment. This is typically achieved by periods of ample food as well as periods of fasting (calorie restriction is not fasting). On a daily basis you can restrict your eating window to 4-6 hours. On longer scale it is useful to do periodic changes to your diet (for example intermittent fasting with restricted carbs and calories for 2 months, then follow with 2 weeks of higher calories and carbs).
* Bad stuff are sugars and almost everything that is highly processed, refined, enriched, etc. Meat from unhealthy, stressed animals. Getting rid of all or almost all carbs is desirable as long as some carbs are in the diet from time to time to exercise your insulin.
* Mitochondrial decouplers are substances that cause your mitochondria to waste energy. Wasted energy is heat. For example (I think...) by supplying myself with mitochondrial decouplers I have shifted my temperature comfort level by about 5C. I can now walk, run, sleep, work at about 5C lower that I did before at the same comfort level. What are mitochondrial decouplers -- polyphenols, medium chain triglycerides, caffeine, ketone bodies, etc.
* Low intensity training (I started running about 30 minutes daily at conversational pace) causes your body to develop more mitochondria. More mitochondria present better opportunity for the body to waste heat as well as host of other useful adaptations. You don't have to be running -- taking a brisk walk after your last meal of the day is a fantastic way of getting some activity as well as efficiently clearing blood sugar and improving effective insulin sensitivity (insulin sensitivity is your ability to clear blood sugars, exercise does not improve insulin sensitivity directly but helps clear the sugar making it as if insulin was more effective).
* Exposing body to cold. You don't need to start getting cold therapies -- if you live in colder climate like me it is enough to just not avoid cold at all cost. I am running daily regardless of weather and I am wearing clothes just enough to get mostly comfortable after say 15 minutes of running in -2C but maybe a little cold at the start.
* Consistently good night of sleep is a must.
* High stress can cause blood sugar and insulin resistance. Body reacts to stress by releasing sugar (to prepare you for effort). But chronic stress causes chronic blood sugar causes chronic insulin causes you getting fat and unhealthy.
* Carbs cause insulin (duh) which causes:
** fat in your fat stores being unavailable to your body as an energy resource,
** when the fat stored in your body is unavailable to your body you will be hungry even in the presence of hundreds of thousands of calories on you (which is crazy if you think about it),
** your brain is built to seek more carbs when you get hungry.
* Fats don't make you fat. People on keto diets quit keto when they finish losing weight because they find they are unable to eat so many calories as fats and they consistently undereat or change their diets unwittingly.
* If you have to eat carbs, make effort to reduce their impact. Never eat "naked" carbs -- preceding carbs with fats and/or protein can significantly lower glycemic index. Preceding fats with acids deactivates enzymes in your saliva that cause about 40% of carb digestion in your stomach -- effectively lowering glycemic index (sushi has only 40% of glycemic index of same portion of plain rice -- due to rice vinegar added to the sushi rice). Taking a walk right after carb meal helps body clear blood sugar faster (for example 20 minute brisk walk right after a meal can shorten aftereffects of the meal from 5 to 3 hours).