@antimatter
A very basic way to understand hunger is I think the way you are looking at it: reduced blood insulin promotes access to fat stores through glucagon production and the associated breakdown of body fat by the liver.
If you can access energy on a constant basis, then you are not hungry.
In reality, the body's processes are a lot more complicated, especially for people who have a high body fat content. Very fat people often will struggle to lose weight more than people moderately fat.
I think I mentioned the term insulin resistance earlier on. As a reminder, this is when your cells resist accepting the nutrients brought to them by insulin because your body has produced too much insulin over a long period of time. This happens mainly with very overweight people. Nutrients not accepted by cells get stored as fat so the fat storing vicious cycle is worse ... Also really bad is the fact that the nutrients are not absorbed like they should be so the body is often undernourished even with all this food consumption. Paradoxical, right?
Anyway, there is a similar concept with respect to hunger. I'm going to ignore a hormone called Peptide YY which regulates short term eating and focus on leptin below ...
Leptin is often referred to as the satiety hormone - when present, one normally doesn't feel hungry. It regulates satiety over the long term, unlike peptide YY which regulates it from meal to meal.
Leptin gets released from body fat cells; it is therefore present in the blood in an elevated state in people who are fat.
Similarly to people who are insulin resistant, people with a high body fat %age can become leptin resistant - ie no longer sensitive to the signal that makes them feel satiated. This partly explains why fat people are often so hungry - which had never made sense to me: why would someone with so much energy around the belly ever be hungry?
So if anyone ever criticises fat people for not having any 'self control', you now know it's complete BS. The reason is physiological (and can be addressed) not necessarily willpower (though emotions can trigger hormones in an adverse way as well so I don't think I can say it is not psychological).
Apparently, leptin levels in the blood increase exponentially with body fat percentage, making very fat people feel even less satiated and encouraging thus them to eat more.
A few things to bear in mind to break the oversupply of leptin to get the hypothalamus sensitive to leptin again (if this is your situation - likely if your body fat % is high):
- Fasting reduces leptin. So IF would be helpful here
- Exercise reduces leptin. Makes sense that it should make room for a hunger hormone called ghrelin to trigger hunger
- Insulin increases leptin production (wherefore the need to reduce carb intake to reduce blood insulin levels)
- Testosterone reduces leptin and estrogen increases leptin. IF increases testosterone production as does exercise with heavy weights
So ... if you're overweight there is a good chance you are leptin resistant.
Break the hunger cycle through heavy weight exercise (training fasted is best), IF and reducing carb intake.