My pet theory is "refined sugar and other simple carbs'. Simple carbs spike up blood sugar through the roof, the body responds by dumping insulin, the insulin

My pet theory is "refined sugar and other simple carbs'. Simple carbs spike up blood sugar through the roof, the body responds by dumping insulin, the insulin causes blood sugar to be sequestered in fat and muscle cells (as intended), but if the dump is large it may overshoot and the blood sugar falls through the floor. Aka "sugar crash". The crash will of course make you crave food again, the same simple carb kind. Vicious cycle. This sort of see-saw messes you up real bad. So I was told [1] [1] https://www.amazon.com/Why-We-Get-Fat-About/dp/0307474259 https://www.amazon.com/Why-We-Get-Fat-About/dp/0307474259