Resistance to Leptin and Danger of High Fructose Corn Syrup
The most important impact on leptin by high fructose corn syrup is the development of a condition known as leptin resistance within the body. When resistance to leptin occurs, the body can no longer respond to the regulatory benefits of the protein.
Researchers from the American Physiological Society showed in 2008 that high levels of fructose can slowly cause leptin regulation to cease functioning properly. Over the course of six months, two different groups of rats were fed high fructose and fructose-free diets. During the time period, no identifiable differences existed between the rats save for one: higher triglyceride levels in the high fructose diet specimens.
At the end of the six months, both sets of rats were injected with additional leptin to see the effects on the animals' eating levels. Due to the higher level of leptin, the rats should consume less food. However, the rats that consumed high levels of fructose did not lower their food intake levels, while the low-level rats ate less. This means that high levels of fructose creates a situation where normal leptin interaction becomes suppressed within the body. Essentially, too much high fructose corn syrup caused leptin resistance. The rats with this condition ultimately suffered from high levels of weight gain.
This was the first study to demonstrate that leptin resistance can be brought on by high fructose consumption.