All That Holiday Sugar May Weaken the Immune System

It’s that time of year again: gathering with family and friends, more social commitments, and sugar everywhere you turn. You’re probably heard that all this sugar isn’t good for your waistline, but have you heard that sugar may also have a direct, negative effect on your immune system?

In a large 2020 review published in the journal Nutrients, researchers looked at the link between diet quality and immune imbalance in children and adolescents, and found that a healthier diet (such as the Mediterranean diet, fruit and vegetables, or macro/micro nutrients such as fiber or vitamin C and E) was linked to lower levels of unhealthy immune activation, while an unhealthy diet rich in added sugars was linked to elevation in inflammatory markers. 

In adults, higher consumption of sugary drinks has been similarly linked to elevated markers of inflammation. 

A new study published in 2022 examined how sugar may influence the immune system via the microbiome. Researchers found that sugar changed the microbiome in a way that threw the gut immune system out of balance and could lead to a higher risk of health issues, including obesity and metabolic disease. The researchers found that eliminating sugar from high-fat diets protected mice from obesity and metabolic syndrome.

There’s still more to be learned about the connection between sugar and immunity, but most experts recommend limiting added sugar for health. As the holidays approach, read your labels, try to choose more whole foods instead of highly processed foods, and eat a good quality diet, high fruit and vegetables, whole grains, fiber, and healthy fats.