Obesity and too many calories can worsen diseases such as multiple sclerosis. But diet can become a supportive therapy.
The brain can also become “inflamed”. And when it happens it’s not a good thing, because neuroinflammation is co-responsible for many scary diseases, from multiple sclerosis to Alzheimer’s. The Spoke 7 researchers, coordinated by Gabriela Constantin who directs the Laboratory of Neuroimmunology and Neuroinflammation at the University of Verona, study the dialogue between neurons and immune cells.
Normally, the latter circulate in the blood and interact little with the brain. In the presence of a disease, however, they can enter the brain tissue, and then the dialogue becomes a conflict. Immune cells release molecules that damage neurons and they die, promoting neuroinflammation and neurodegeneration: this happens in Alzheimer’s and multiple sclerosis.
It is precisely in these pathologies that Mnesys researchers have discovered that even what we eat can interfere, for better or for worse, in the “communications” between the brain and the immune system.
“We have known for some time that the metabolic and nutritional state has an effect on immunity”, explains Giuseppe Matarese, coordinator of research on the metabolic regulation of the immune response in multiple sclerosis and professor of general pathology and immunology at the Federico II University of Naples. «When we eat, adipose tissue produces a hormone, leptin, which inhibits the brain’s hunger center, signaling that we have enough energy stored in the form of fat and therefore reducing further food intake. However, leptin has pro-inflammatory effects: the more there is, the more the immune response “turns on” and vice versa. In the case of malnutrition, for example, leptin is scarce, signaling that the body has little energy, the immune system functions less and one becomes ill more easily from infections.”
The exact opposite happens when we eat too much: leptin is abundant, the cells of the immune system are hyper-active and thus both general inflammation and inflammation in the central nervous system increase, as well as the risk that some immune cells “go crazy” and end up attacking the body, triggering an autoimmune disease. “It is no coincidence that many neurological diseases such as Alzheimer’s, Parkinson’s and multiple sclerosis are more likely in people with obesity,” Matarese points out.
help with medications
A study by the Matarese group clearly showed how crucial nutrition is in multiple sclerosis. Food overload has in fact altered the animals’ immune responses, promoting inflammation and boycotting the mechanisms that prevent autoimmunity.
On the contrary, by reducing calorie intake, the disease improved.
In light of these results, we tried to replicate the approach in patients, testing a slight caloric restriction associated with the therapy in a clinical trial. «We are still analyzing the data, but preliminary evaluations indicate that decreasing daily calories by 15-20% improves the response to drugs and can therefore be a valid supportive therapy. We know that overweight people, in addition to having a greater risk of multiple sclerosis, also have a more severe disease, with more relapses and more disabilities. Reducing the metabolic load by decreasing calories can help control immunity and improve the effectiveness of drugs such as dimethyl fumarate, but it is important to underline that diet can never replace them.”
Researchers have also tried to understand whether specific nutrients should be preferred or avoided over others: for example, diets enriched in carbohydrates, fats or proteins were tested in mice to evaluate their effect on inflammation.
As Matarese says, «the quality of nutrients also matters: carbohydrates are more “inflammatory” than fats, which are more “inflammatory” than proteins. This is also why the ketogenic diet, which eliminates carbohydrates, has a powerful anti-inflammatory effect: it involves the formation of ketone bodies which eliminate hunger and have a strong anti-inflammatory action. However, the strict ketogenic diet cannot be followed for more than three to four weeks maximum. And even a strong caloric restriction is not feasible, especially in patients already suffering from a difficult disease such as multiple sclerosis. The most realistic way to enhance the effect of the drugs and control inflammation could be that of a mild caloric restriction that mainly reduces carbohydrates.”
