Discover What Happens to Your Body When You Stop Eating For 3 Days. Fasting has many benefits that may extend far further than just the 16 hour fasting window attributed to typical intermittent fasting plans.

"After about 6-10 hours without food, most of the leftover carbohydrates from your previous meals will be used up for fuel. As a response your pancreas will secrete glucagon, a hormone, that makes your body release the stored glucose from your liver and your muscles. Your hunger hormone ghrelin will rise making you feel hungry. After 10 hours your pituitary gland will boost the production of Human Growth Hormone which will help delay muscle loss much longer than most people think. Your body temperature may also drop and you'll start feeling colder than usual. After 16 hours your body will become more reliant on burning fat for energy and ketone production will increase. At around this time, autophagy will kick in which is a process where your body will recycle any junk it finds such as damaged proteins, bacteria, or dysfunctional cells. This boosts immunity and reduces inflammation. 24 to 32 hours in your body will run out of glycogen and become entirely reliant on its own fat stores for energy while reducing protein breakdown rates substantially to spare muscle tissue. About 48 hours in you'll experience improvements in your mood, alertness, and tranquility. After 3 days of fasting, muscle catabolism becomes an actual issue and nutrient deficiencies may slowly start to emerge."

After you eat a meal, food is broken down into simpler molecules and used as fuel so your body can function properly. An organ in the abdomen known as the pancreas produces insulin which is a hormone that helps your cells absorb the glucose found in the bloodstream after a meal. Dietary fat, on the other hand, is broken down into fatty acids which are used by the body for energy as well as for many different biological processes like testosterone production for example. Excess fatty acids are converted back to triglycerides and then most of those triglycerides are stored in adipose tissue otherwise known as body fat.

Meanwhile, excess carbohydrates from that meal will first get converted into glycogen which is a string of glucose molecules that can be stored and used later. Glycogen is mostly stored in the liver and your muscles. Since there's a biological limit to how much glycogen a person can store, once that limit is reached the rest of the excess energy is converted into triglycerides and once again stored as adipose tissue. This is the routine process that our bodies go through when we eat throughout the day. But what would happen if you were to totally stop eating for 3 days?

Well after about 6-10 hours of fasting, most of the leftover glucose that's still circulating in your bloodstream will be used for fuel. Since your body is not receiving any new nutrients, it has to start using its own glycogen reserves to fuel itself. It's at that point that the pancreas secretes glucagon. Glucagon is not the same as glycogen or glucose. It's actually a hormone, and one of its jobs is to signal your body to release glycogen and fatty acids. Also if your last meal was low in carbohydrates your body may start producing ketones as an energy source within this early stage of fasting. Ketones are chemicals produced by the liver when fat cells are converted into fatty acids. So in general during those first 6 hours, your blood glucose levels will start to elevate and then they'll gradually decline. Meanwhile, your ketone levels, will do pretty much the opposite. They'll gradually rise, especially after approximately the 10th hour of fasting. (1)

Now before you ever hit that 10th-hour mark, if you’re accustomed to eating three meals per day or you regularly eat a high-carb diet you'll probably experience hunger and low energy levels. The hunger you feel isn't only due to being low on calories. In fact it's largely tied to your circadian rythm. Your body has gotten into a pattern and now expects food at the certain times of the day that you normally eat. This is due to the hunger hormone ghrelin, which has the effect of stimulating your appetite when it's released. So if you stop eating studies show that ghrelin will spike automatically around the times of the day that you typically have your meals which usually would be breakfast, lunch, and dinner (1) and that spike will make you feel hungry. (1) If you continue fasting, these hunger pangs will subside after about 2 hours, and your body will naturally adapt to a new meal frequency over time.

After fasting for at least 10 hours your body will also start to increase the levels of a hormone produced by the pituitary gland called Human Growth Hormone otherwise known as (HGH). Fasting can actually increase HGH just as much as exercise, stress, or hypoglycemia. (2) HGH plays an important role in the fasting process because it's associated with enhanced muscle repair, exercise...