Polish scientists have developed the POLA index that assesses whether a diet includes the right amount of ingredients necessary for the optimal functioning of the immune system.
In a nutshell, it can be assumed that different nutrients interact with the cells of our immune system, as well as the intestinal microbiota, modulating the body’s immune response and affecting, for example, resistance to various types of infections, including COVID-19.
Based on the results of the POLA index, dietitians and doctors will be able to suggest changes in eating behavior to patients in order to improve immunity and reduce the risk of infection.
The inspiration for the scientists was the COVID-19 pandemic. The dynamic increase in the frequency of infections with the SARS-CoV-2 virus has initiated a worldwide search for protective strategies against the new pathogen. Ph.D. Jagielski’s team also dealt with this topic: from July 2020 to January 2021, they conducted a research project aimed at assessing dietary behavior, physical activity, body composition and intestinal microbiota of vegetarians and people eating traditionally.
“Numerous studies have shown that many modifiable and non-modifiable factors affect the functioning of the immune system. Non-modifiable factors cannot be changed or controlled and include genetic characteristics, age and physiological state. At the opposite end of the spectrum are modifiable factors that can be changed to varying degrees, and these include e.g. eating behavior, physical activity, body weight, sleep duration and stress.”, the researchers from Krakow explain.
Dietary components are the key factor supplied with a daily diet:
“When it comes to dietary components that are taken into account by the POLA index, they include: fat-soluble vitamins (A, E and D), water-soluble vitamins (C and B), selected minerals (e.g. zinc, iron, magnesium), precursors of omega-3 and omega-6 polyunsaturated fatty acids (acid linoleic and α-linolenic) and fiber. There is more and more scientific evidence that optimizing the diet for immunomodulating ingredients can help prevent or alleviate some diseases, including viral respiratory infections.”, emphasizes Dr. Jagielski.
In order to practically confirm the effectiveness of the POLA index, scientists from the Jagiellonian University Medical College checked its operation on a group of 95 adults, without comorbidities, using a traditional or vegetarian diet on a daily basis, among whom the risk of developing COVID-19 was then assessed.
It also turned out that people on a diet with a beneficial – according to the POLA index – immunomodulatory effect (BIM) had about 80% lower risk of contracting COVID-19 compared to people on a highly adverse immunomodulatory diet (HUBIM).
Although the POLA index has so far been assessed only in the context of COVID-19, it has – according to researchers from Krakow – a much wider application. And considering that our immune system is constantly exposed to various pathogens, it can be an extremely useful tool. However, further research is needed to implement it in clinical practice.