Nutrition

Junk food, immune system into a tailspin

Junk food, immune system into a tailspin

Junk food sends the immune system into a tailspin. How and why is explained in a recent study from the University of Bonn. (1) Acute inflammation, DNA alteration, hyper-driving diseases such as arteriosclerosis and diabetes

Junk food, immune system into a tailspin

The immune system reacts to an unhealthy diet – for excessive intakes of free sugars, fats and calories – as if it were a bacterial infection.

Thus a strong inflammatory reaction is activated, that continues even after restoring a healthy diet. 

Inflammation, over the long term, might lead to the development of arteriosclerosis and diabetes, illnesses whose occurrence has been increasing steadily in the past decades.

The recent study ‘Global Burden of Disease had already allocated to unhealthy diets the responsibility for 20% of premature deaths, following analysis carried out in 195 countries from 1990 to 2015. The research at University of Bonn can help to explain the reasons. 

Junk food, the study from the University of Bonn

The study from the University of Bonn – that will soon be published in the magazine ‘Cell’ – has implicated groups of research in the Netherlands, United States, Norway and Germany.

Scientists have submitted rats, for a month long, to a ‘western diet’ of our time, rich in sugar and fat, as well as poor in fibers

The unhealthy diet has led to an unexpected increase of certain immune cells in the blood of the rats, especially granulocytes and monocytes’, explains researcher Anette Christ.

The following ‘genomic studies have demonstrated that a western diet had activated a great number of genes in the progenitor cells. The genes involved included those in charge of proliferation and maturation’, adds Prof. Dr. Joachim Schulze from the Life & Medical Sciences Institute (LIMES, Università di Bonn) and the German Center of Neurodegenerative Diseases (DZNE).  

 Junk food therefore induces the immune system to activate an aggressive reaction, resulting in an acute inflammation. And despite the subsequent recovery of a balanced diet, the immune cells and their precursors remain active. Given that the junk food has genetically reprogrammed most of the cells involved.

The ‘junk food sensor’ in immune cells

It has been discovered just recently that the immune system has an innate form of memory’, explains prof. EickeLatz, director of the Institute for the innate immunity at the University of Bonn and scientist at DZNE. ‘After an infection, the body’s defenses remain in a sort of alarm state, so that it can respond more promptly to a new attack’.

In the research, this process hasn’t been activated by a bacteria, but by an unhealthy diet. And scientists have also been able to identify the ‘junk food sensor’ responsible for the activation of our immune system.

A complex intracellular signaling (c.d. inflammasome, NLRP3) recognizes infectious agents and other hazardous substances – in this case, junk food – and releases highly inflammatory mediators. 

Thus activates a change of the genetic information. The inflammasome triggers such epigenetic changes’, carries on prof. Latz. ‘The immune system reacts consequently also to small stimulus with stronger inflammatory responses’. 

Junk food, health hazards

 These inflammatory responses can, in their turn, accelerate the development of vascular diseases or type-2 diabetes. In arteriosclerosis for example, the inflammatory reaction is a direct contributor to the growth of plaque, since the immune cells migrate constantly towards the vascular walls as soon as they are activated. And when the plaques become too big they can burst, causing blood coagulation and the obstruction of blood vessels that can induce strokes and heart attacks.

These findings are of important social relevance’, continues to explain prof. Latz. ‘The foundations of a healthy diet must behold an important part in education more than what they have today. Only this way we can immunize children at an initial phase against the temptations of the food industry. Children have a choice of what they eat every day. We should let them decide consciously regarding their eating habits’.

The Big Food lobbies, in the meantime, have been able to halt the introduction of nutritional profiles, that the European Commission should  have introduced 9 years ago(!), in order to ban the use of nutritional and health claims on junk food. 

Sadly, also with the complicity of Italian trade associations and politicians driven by their lobbyists.

Dario Dongo

Notes 

(1) Anette Christ, Patrick Günther, Mario A.R. Lauterbach , Peter Duewell, Debjani Biswas, Karin Pelka, Claus J. Scholz, Marije Oosting, Kristian Haendler, Kevin Baßler, Kathrin Klee, Jonas Schulte-Schrepping, Thomas Ulas, Simone J.C.F.M. Moorlag, Vinod Kumar, Min Hi Park, Leo A.B. Joosten, Laszlo A. Groh, Niels P. Riksen, Terje Espevik, Andreas Schlitzer, Yang Li, Michael L. Fitzgerald, Mihai G. Netea, Joachim L. Schultze und Eicke Latz: ‘Western diet triggers NLRP3-dependent innate immune reprograming’, on Cell, 1.11.2018, DOI: 10.1016/j.cell.2017.12.013

(2) Latz and Schultze are members of the group of excellency ‘ImmunoSensation’, that researches the innate immune system. Latz is considered a leader in the innate immune field and has been awarded the Gottfried Wilhelm Leibnix Prize – one of the highest scientific awards in Germany – in December 2017

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