Chronic elevated insulin levels are the main culprit. This goes on for years. By restricting calories and intermittent fasting, glucose is consumed first, preferentially. No fat burning can occur unless and until glucose levels are exhausted. This forces the body to mobilize fatty acids, and utilize them for energy. Our bodies were created to do this, Or adapted if you must. There are equal and opposite hormones to Insulin that are produced when in the fasting state. Even down to the tiny cells in our bodies, the mitochondria, they will show a marked preference for glucose. The problem is, over many years the pathways for the uptake and regulation for fat burning become atrophied from disuse. One meal a day will most definitely achieve all these benefits, assuming calories are restricted to basal rate. Under a 1000 calories daily will do this quite effectively for most people. We as a society have become “Sugar burners”. Glucose is great for extreme exertion, but it is a toxic poison for sedentary people. It’s like rocket fuel. I’ve likened it to the AFR in a gasoline engine. Too much fuel, and idling all day, no load on the engine - fouled spark plugs, and sludge buildup in the crankcase, etc. Intermittent fasting and calorie restriction is very similar to exercise - it is a metabolic workout. Blood sugar, blood pressure, blood lipid parameters such as HDL/LDL, cholesterol markers are all improved by this. No Pills required. Amazing, huh?
I learned something new in each sentence.