I don’t see this most frugal approach for those who have been saving up and storing their own energy. If you have any fat at all, you can do water fasting for several days or weeks without any ill health, in fact, your health will typically greatly improve. If you are Ty 2 diabetic, you can reverse/cure it 100% with fasting. Look up utube, Dr. Jason Fung “The Aetiology of Obesity” and watch all 6 hours. This will open your eyes to many things about Obesity, fasting, Diabetes, heart disease and many other diseases that can be cured or remedied via the thousands of years of practice. The world record fast is 480 days for >600 lb individual. You will lose about 1/2 lb per day via fasting and you consume >95% fat, nearly no muscle is consumed as HGH increases 10-15X for muscle protection. That’s why body builders practice fasting methods to boost this!
The key here is insulin resistance, eating too much, eating to many times, etc. You get to the poiont where insulin levels are double or triple normal, all the time. Eat once a day, at least do this all the time.
If you are skinny, do not fast. If you have more than 15% body fat, then go ahead. If you are obese or morbidly obese, fasting will reset your hormone levels and reduce your setpoint. It is the easiest thing to do, nothing to keep track of, cheap, huge savings in food, shopping time, etc. Sometimes it takes a few weeks or months, so you will have to keep at it. In fact, I would change to only eating betwen a few hours each day so you can fix insulin resistance the rest of your life.