The epidemics of weight and obesity problems are caused by various factors that lower the metabolism. Perhaps the most evident of these factors is the excessive use of sugars and refined carbohydrates (bread, pasta, flour, rice, sweets, chocolates, candies, etc.) Nothing has contributed more to the rampant obesity epidemic than the excessive consumptions of refined carbohydrates.
I should clarify that carbohydrates are necessary foods. However, there are different qualities of carbohydrates: Natural carbohydrates and refined carbohydrates. Natural carbohydrates are those that are in their natural state without having been industrially manipulated by humans. Examples are vegetables and fruits. Refined carbohydrates are modern products created by the food industry that have gone through a variety of polishing, bleaching, grinding and refining.
Within the natural carbohydrates there are some carbohydrates that have a very sweet flavor. The sweet carbohydrates can come from "natural" sources but the fact that they are sweet indicates they are very high in sugars like fruits that can turn into fat. Examples of very sweet carbohydrates can be fruits like bananas, mangoes, and raisins. There are fruits that aren't excessively sweet like strawberries, apples, and pears, which are acceptable as "natural" carbohydrates.
When carbohydrates are industrially processed they lose a good part of their nutritional value (vitamins and minerals) and they turn into foods that can easily make us fat. The industry processes to refine carbohydrates are rather harsh. These foods are so refined that the human body can quickly turn them into glucose without much effort. Bear in mind that anything that causes and increase of the bodies glucose will create excess body fat.
When we eat a doughnut (wheat flour with sugar) the body quickly turns that into a large amount of glucose in our blood which sets the scene to gain weight. Those are the mechanics involved in the process of becoming overweight: lots of refined carbohydrates that turn into excess glucose that later become accumulated body fat with the help of the insulin hormone.
carbohydrates are addictive
Perhaps the most harmful aspect of refined carbohydrates is their strong addictive power. Yes, refined carbohydrates are addictive. When your body has a craving for something, what does it crave? Does it crave meat or cheese? Or does it crave chocolate, candy, ice cream, bread or cookies? Notice that the body only craves refined carbohydrates. Refined carbohydrates are like a drug for an addict. People that are addicted to carbohydrates can't control themselves.
The consumption of their refined carbohydrates in excess doesn't only cause an addiction; it also causes a state of acidity in the body that decreases the metabolism. the excess of refined carbohydrates converts into excess glucose in the blood once it has been digested. Part of the excess glucose ferments within the body and turns into lactic acid, which created an acidic state that reduces oxygen and decreases metabolism.
A recent scientific discovery showed that the excess of refined carbohydrates turns into excess glucose (sugar in the bloodstream) which then forces the body to produce an excess of the hormone insulin and this hormone at the same time interferes with the hormones of the thyroid glands and brings with it all of the signs of hypothyroidism, including depression. People that are addicted to refined carbohydrates then start to have problems with their thyroid because their bodies produce an excess of insulin that interferes with the hormones produced by the thyroid.