What's really going on behind the scenes when you overeat, according to Sementelli, is the release of insulin due to there being more glucose (sugar) in the blood than what the body needs. Insulin signals your cells to "store the excess glucose in the liver and release it when your blood sugar is low or when you need more energy between meals or during exercise."
Basically, overindulging can send your blood sugar sky-high while insulin works to store it away, but this also means you'll suffer the subsequent blood sugar crash a few hours later. This is behind some of the symptoms we've already looked at, but it can also cause nervousness, irritability, and difficulty concentrating.
You may feel compelled to reach for a sugary snack to get your blood sugar levels back up to normal, but the best thing you can do to get back on an even keel is to go for something more balanced — try a fresh green salad with lean protein, avocado, and some whole-grain crackers or some toast and eggs.
