If you believe the results a study that is currently in the Obesity journal published, the main culprit in obesity is none other than fructose. But as always with studies on fat and thinness, nothing is black and white.
Fructose is a simple sugar or monosaccharide, also known as fruit sugar. It occurs naturally in honey and in various fruits and vegetables. It is by far not the largest source of calories typically consumed by humans. According to the researcher Richard Johnson from the University of Colorado However, fructose has another side effect: it increases the desire to eat more and eat fattier foods. 
A balanced diet that includes fruits and vegetables that contain fructose will not be a problem. It will be difficult to consume too much fructose from fruit. The situation is different with products that have added sugar.
In their study, Johnson and colleagues examined the effects of many different risk factors for obesity and tried to find a common denominator even in seemingly contradictory circumstances. The scientists found that the metabolism of fructose in the body leads to lower levels of ATP, or adenosine phosphoric acid. This compound is of great importance for the metabolism of organisms and is a source of energy that drives the biochemical processes that occur in organisms. When ATP levels reach a sufficiently low level, the body is signaled that it needs more "fuel". Our "fuel" is food, so when ATP levels are sufficiently low, we feel hungry.
According to Johnson, fructose is the unifying factor in many hypotheses and theories about what contributes to obesity - fructose encourages our metabolism to go into "empty tank" mode, causing us to lose control of our appetite and crave fatty foods. This process is triggered even when the body still has energy reserves in the fat already stored. 
In some cases, this may even be beneficial. For example, if you are a bear preparing for hibernation and feeding, then it is good if fructose intake promotes processes that protect the already stored fat - which the body needs as "fuel" during hibernation. But for a person who consumes sugary foods and drinks, this process will do more harm than good.
"This is an evolutionary mechanism that helps animals store fat before an impending period of fasting. In the short term (e.g. during hibernation) this process helps, but when it becomes chronic, the benefits are replaced by the risk of various harms," the authors write. the study .
Much of the research to date on the role of fructose in the body's metabolism is based on animal studies, so Johnson's team recognizes that there is still a lot of work to do before we fully understand all of the major risk factors for obesity.
Link to study at the National Library of Medicine here .
Link to the original article: https://www.delfi.lv/campus/56036780/zinatne/56054232/jauna-petijuma-apgalvo-ka-atrasts-galvenais-aptaukosanas-grekazis