How do fructose induce inflammation

FRUCTOSE-INDUCED INFLAMMATION AND INCREASED CORTISOL: A NEW MECHANISM FOR HOW SUGAR INDUCES VISCERAL ADIPOSITY

This article is written to explain the hypothesis of fructose linked to visceral fat and that lead to what we called it TOFI term: “thin on the outside, fat on the inside,” and thus individuals who are more metabolically unhealthy than their weight or BMI would indicate.

We all know that obesity is defined by energy imbalance when you eat more than you burn. Another hypothesis for visceral adiposity is insulin resistance due to consumption of refined carbs and sugar that lead to fat storage. But a new hypothesis has been developed considering visceral adiposity which is due to overconsumption of fructose that lead to inflammation.

Fructose can be absorbed by many tissues like adipocytes, the kidneys, muscles, and brain. Fructose consumption cause direct inflammation through different mechanism. Fructose can affect leptin, reactive oxygen species, and increased cellular cortisol levels. The result will be insulin resistance at the level of adipose tissues and there will be increased reflux of fatty acids out of subcutaneous tissues.

These fatty acids are deposited in the liver, which also has upregulated fatty acid production due to the intake of sucrose. Normally, these absorbed and produced fatty acids are secreted as very low-density lipoprotein (VLDL) and released into the blood. However, when the flux of fatty acids into the liver exceeds what VLDL production can remove, fat begins to deposit in the liver itself. This leads to hepatic insulin resistance and further increases VLDL production and, eventually, liver inflammation.

Finally, fructose consumption is directly triggers pathways leading to insulin resistance (especially in the liver and fat tissue), inflammation, and increased cortisol levels, which collectively make fructose specifically harmful in ways other carbohydrates are not.

Sources:

https://www.crossfit.com/essentials/fructose-induced-inflammation-and-increased-cortisol

https://www.acs.org/content/acs/en/molecule-of-the-week/archive/f/fructose.html