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High fructose diets could cause immune system damage

University of Bristol

sugar sweets

This new study shows that fructose causes the immune system to become inflamed and that process produces more reactive molecules which are associated with inflammation - this could lead to disease.


Foods and diets high in fructose have long been linked with metabolic problems including non-alcoholic fatty liver disease, Type 2 diabetes and obesity. 

This study shows for the first time that fructose can also cause immune system changes that promote inflammation - which is associated with these and other 'non-communicable diseases'.

Inflammation also affects brain development and function, and excessive or chronic inflammation is linked with many developmental and mental health conditions, including ADHD and autism, depression, and dementia.

Fructose makes up half of ordinary table sugar, and a slightly higher proportion of high fructose corn syrup. 

Fructose is also found in fruits and sweet vegetables, but when consumed in these natural, whole foods - in moderation - it is not considered to be problematic for most people, as
(1) the dietary fibre in these foods slows its release, and also prevents over-consumption by regulating appetite, and
(2) the many important nutrients found in vegetables and fruits also help to protect against negative effects

By contrast, abundant evidence indicates that the high fructose content of ultra-processed foods and many soft drinks (as found in typical modern western-type diets) - IS a major contributor to physical and mental ill-health.

This study provides yet another potential mechanism by which high fructose intakes from these sources can damage health.

For the related research article please see:

And for another recent and important insight into the negative effects of fructose, as consumed in ultra-processed sugary foods and drinks, see also:

For further information on this topic, please see the following lists, which are regularly updated:

22/02/21 - Medical Xpress

New research by Swansea scientists in collaboration with researchers at the University of Bristol and the Francis Crick Institute in London has indicated that consuming a diet high in the sugar fructose might prevent the proper functioning of peoples' immune systems in ways that has, until now, largely been unknown.

Fructose is commonly found in sugary drinks, sweets and processed foods and is used widely in food production. It is associated with obesity, type 2 diabetes and non-alcoholic fatty liver disease and its intake has increased substantially throughout the developed world in recent years. However, understanding the impact of fructose on the immune system of people who consume it in high levels, has been limited until now.

The new study published in the journal Nature Communications shows that fructose causes the immune system to become inflamed and that process produces more reactive molecules which are associated with inflammation. Inflammation of this kind can go on to damage cells and tissues and contribute to organs and body systems not working as they should and could lead to disease.

The research also brings a deeper understanding about how fructose could be linked to diabetes and obesity—as low- level inflammation is often associated with obesity. It also builds on the growing body of evidence available to public health policy makers about the damaging effects of consuming high levels of fructose.

Dr. Nick Jones of Swansea University's Medical School said: "Research into different components of our diet can help us understand what might contribute to inflammation and disease and what could be best harnessed to improve health and wellbeing."

Dr. Emma Vincent in the Bristol Medical School: Populational Health Sciences (PHS) added: "Our study is exciting because it takes us a step further towards understanding why some diets can lead to ill health."