High-fructose corn syrup and other processed sugars seems like innocent ingredients in packaged foods and condiments. Many of us know, however, that added sugar can take a serious toll on the body. High-fructose corn syrup (HFCS) in particular is linked to weight gain, insulin resistance, and fatty liver disease. Now, more research is showing that HFCS and other sugars consumed in excess may even damage the immune system.
A 2019 study published by The Journal of Translational Immunology suggests that high consumption of high-fructose corn syrup can lead to inflammation in immune system cells. Scientists discovered this by comparing the effects of fructose and glucose on human dendritic cells.
As described by the British Society for Immunology, dendritic cells (DCs) are critical cells that ignite the body’s reaction to foreign substances and regulate the immune system’s response. When DCs were exposed to high-fructose corn syrup, they incited an inflammatory response that was considerably greater than the response created by glucose.
Though researchers were unable to identify the specific mechanisms that caused immune dysfunction, they laid the groundwork for other scientists to build on their findings. This is exactly what happened, as a 2021 study published in Nature Communications confirmed that a diet high in fructose may lead to an over-active immune system. The study also proved that fructose can increase inflammation independent of a person’s pre-existing diseases, such as a diabetes or fatty liver disease.
During the experiment, which was conducted at several research centers in the United Kingdom, scientists compared the reactions of both human immune-system cells and mouse immune-system cells to high levels of fructose. The cells were extracted from blood samples, which were analyzed after being exposed to fructose for two weeks.
Upon analyzing the data, the researchers learned that fructose initiated an inflammatory response by increasing cell production of cytokines. For those who aren’t aware, cytokines are small proteins that help cells communicate and signal where the site of an infection is located in the body.
Why do certain types of sugars cause this response? Investigators from the 2021 study are still learning how and why the immune system reacts to high levels of fructose in this way, but they believe that fructose “reprograms” immune-system cells.
It’s important to note that the amount of sugar you consume may be more important than the type. While the 2019 study suggested that high-fructose corn syrup in particular damages the immune system, some health experts believe that HFCS is no more harmful than other sugars. The Food and Drug Administration (FDA), for example, states that HFCS and other types of sweeteners may be equal in the harm they pose. The administration therefore suggests that you limit your intake of all added sugars.
Still, many studies have established the increased health risks associated with HFCS as opposed to all sugars. Why might corn syrup in particular cause such issues? One reason may be that it gets added to foods that already have unhealthy ingredients. In other words, foods containing corn syrup often have very little nutritional value, which translates into a poor diet and an increased risk for certain diseases.
In contrast, foods that contain naturally-occurring fructose, such as apples and oranges, have great nutritional value. They also contain less sugar than processed sweets.
Does this mean you have to give up your sweet treats for good? Not necessarily! Simply reducing your consumption of high-fructose corn syrup and other added sugars may significantly help your immune system combat inflammation.