We all eat. When we do almost all the carbohydrates consumed turns to glucose (sugar). It is an important energy source used by the cells and organs of our bodies. Some examples are our muscle cells and our brain. Carbohydrates such as bread, rice, pasta and fruit converts into glucose. It is then absorbed into our bloodstream.
An organ called the pancreas then produces a hormone called insulin. This hormone is the key which allows glucose to enter our cells. The extra glucose is stored as glycogen in our liver and muscle. Any remaining glucose converts to free fatty acids and stored in our fat cells. Once glucose is out of our bloodstream insulin closes the doors to our cells and leaves our body.
We have energy from foods for our body to use for 2 to 3 hours. After, we need another source of energy because our blood sugar levels get low and we feel weak. When our body has used up all our glucose it turns to stored fat for energy. Our fat cells release the free fatty acids back into our bloodstream to feed our cells. No insulin is needed to open the cell doors. Hence the term "free" fatty acids.
This is the simple process of storing fat. You store fat when you have too much glucose and burn fat when you don't have enough glucose. This is how your body should work. You eat healthy and follow a cycle where it ultimately burns fat.
Instead, we store a lot more fat than our body burns. We eat refined process foods like sugary cereals, candy, white bread and soda. This enters our body and quickly turns into glucose. Our blood sugar rises quickly. Insulin is then released by our body to handle the high amounts of glucose in our blood stream. The hormone insulin, does its job. It opens our cells so it can use the glucose and stores the excess in our fat cells.
However, it takes a while for insulin to leave our body. Our blood sugar goes down but the level of insulin in our body remains high. This is a problem. As long as there is insulin in our body our cells can't access the free fatty acids in our body. Free fatty acids don't need insulin to allow them into our cells. They do need insulin to be gone before they can enter them.
This will mean that your cells will not fed on the free fatty acids. You will now begin to feel hungry and continue eating bad foods. Now there's a problem. More glucose enters your blood stream causing insulin to be released again. It opens the doors to your cells and feeds it glucose. Unfortunately, the excess glucose is then stored in your fat cells again. Remember, the excess fat from before was not used by your body. When our insulin levels remain high we continue adding to the fat storage but never using any.
This cycle repeats itself over and over. The refined and processed foods we eat causes high levels of insulin and high levels of fat storage. To make matters worse since fat is a concentrated source of energy your body does not need a lot. It provides twice as much energy as carbohydrates and protein.
https://www.youtube.com/watch?v=8ij3k50-C28 (video to embed
How the average person's body uses glycogen when they exercise then fat. http://www.livestrong.com/article/307905-glycogen-and-weight-loss/
Glycogen is carbohydrates broken down by your body and stored in your liver and muscle. An adult can store about 400 grams in the liver and 100 grams in their muscle. Every gram of glycogen has about three grams of water.
During a person's first few weeks of weight loss they usually lose a lot of water. Ever heard of water weight? This occurs because as the body burns glycogen for energy it releases the water attached to it. There is no fat loss only glycogen and water depletion.
The time it takes someone to use up their glycogen stores when they workout depends on their level of fitness. When glycogen is used up the body then uses fat for energy. The process for using fat for energy is less efficient so your performance declines.
Fat simply explained,
How you get it and how it is stored (video)
Why you need it, how it is used, why people have to much of it
How to get rid of it (nutrition, exercise and mindset)
So what hope is there for weight maintenance? http://www.nytimes.com/2016/05/05/health/short-answers-to-hard-questions-about-weight-loss.html
Anecdotal reports by people who have succeeded in keeping weight off tend to have a common theme: constant vigilance, keeping close track of weight, controlling what food is eaten and how much (often by weighing and measuring food), exercising often, putting up with hunger and resisting cravings to the best of their ability. Those who maintain a modest weight loss often report less of a struggle than those trying to keep off large amounts of weight.