Usually on intermittent fasting you have a 4-6 hour window in where you have to eat the same amount of calories as you would in an entire day.
Most people pick some time around noon for the start of this eating window.
Fitting all you calories of the day in just 1 meal is really hard and unnecessary, spread it out over the 4-6 hour window.
Depending on your age/bmi/sex/activity and so on the amount of calories you need differ.
If you consistently eat WAY under your daily usage of calories then your body will adapt and it will be harder to lose weight + negative effects overall on hormones and brain chemistry.
Note that this method does not work for everyone as we are all different.
I tried this several years ago while i was working a physically demanding job with alternating shifts, it didn't work for me.
On the subject of obesity and diabetes:
A recent study found that after weight loss about 50% of the subjects didn't have diabetes type II anymore.
I'm no dietary expert but from what I gather the following dietary rules are good to abide:
- Eat enough veggies, green and other ones
- 1-3 pieces of fruit a day, this one is not essential but it's a good source of vitamins and fiber
- keep red and processed meats to a mininum, instead opt for lean meat and fish, seafood.
- try to eat meat only 4-5 times a month.
- a handful of nuts a day
- drink enough water
- avoid sodas and any other crap with added sugars
- put some variation in your meals
- 1 glass of alcohol minimum per week (abstainers and excessive drinkers have an increased risk to develop Alzheimer)
- make sure you have enough dietary fiber in your diet
- don't eat too much bread
I myself am a fan of rolled oats where I add seeds and nuts and fresh fruits with milk/boiled water in the morning.
Then have a medium meal early afternoon and a light dinner in the evening. With the occasional full day of fasting when I have a day where I sit on my ass all day