Dietary Fiber Fights Flu Damage

Dietary fiber has a protective effect against chronic inflammatory diseases, reducing immune responses involving short-chain fatty acids. In this regard, it is suspected that in the case of a viral infection, these anti-inflammatory properties may impair the development of protective immunity. In contrast, laboratory models have found that high-fiber foods in influenza infection improve recovery and survival in influenza in two ways.

On the one hand, this type of diet affects the activity of the bone marrow, in such a way that it reduces the mobilization of neutrophils to the airways, which limits the tissue damage that occurs there in the fight against the virus.

On the other hand, short-chain fatty acids extracted from food enhance the activity of CD8 lymphocytes, improving their metabolism.

 
In this way, dietary fermentable fiber and short-chain fatty acids tip the scales of the immune balance of both the primary and adaptive immune response in such a way that both accelerate the healing of influenza infection and limit damage to the immune system. answer.

Fiber and chronic inflammatory diseases

The beneficial effects of dietary fiber and its fermentation products, especially short-chain fatty acids, on a wide range of chronic inflammatory diseases have already been well documented. The effect of dietary fiber on the immune system has been shown to extend far beyond the gastrointestinal tract and can affect peripheral immune responses in tissues such as the lung and brain. Fiber fermentation products such as acetate, propionate, and butyrate suppress immune responses, having an effect on several levels - on dendritic cells, macrophages, neutrophils and regulatory T-lymphocytes. Laboratory models suggest that eating foods rich in fermentable fiber may have a protective effect against inflammation from respiratory allergens. The fermentation products of these fibers affect the immune system in such a way that they increase the accumulation of dendritic cells in the airways, which are less representative of the T-cell allergen. Subsequently, this is a change in the course of the immune response and better respiratory function. Unfortunately, whether the suppression of this pathological immune response, in this case, could have an effect on a general weakening of immunity in the area and possible increased susceptibility to infections is not yet known.

Fiber and flu

Influenza A infection is one of the most common viral diseases worldwide, infecting between 5 and 20% of the population each year, according to WHO data, thus linked to significant morbidity and mortality. Experiments have concluded that dietary fiber and short-chain fatty acids improve the outcome of influenza infection in the two ways described above.

Inulin alters the intestinal microbiome.

The content of dietary fiber can modulate the ratio of different types of bacteria in the intestinal microbiome. The dominance of inulin - a type of dietary fiber - has been shown to lead to the dominance of two types of bacteria - bifidubacteria and bacteroides. These conditions lead to the production of more fermentation products, especially butyrate, the amount of which increases not only in the intestine but also in other tissues. Retrospective laboratory models demonstrate that in such cases, fewer inflammatory infiltrates, less tissue damage, and post-infection hemorrhage are found in the airways.

Which fibers to look for?

Fiber is a diverse group of carbohydrates that the human body is unable to break down. For the most part, they pass through the gastrointestinal tract unchanged. Fermentative fibers are those that can be broken down by bacteria in the intestinal tract, and the result of this breakdown is short-chain fatty acids. The main fibers in this group are pectins, beta-glucans, inulin, and oligofructose.

The best dietary sources of these fibers are legumes and vegetables, and for pectin - apples. Usually, a dose of one cup of these foods provides half of the daily recommended needs.

It should not be forgotten that fermentation is a chemical process in which gases are released and the consumption of large amounts of such foods can cause flatulence - gas formation - and stomach discomfort, especially for people who are not accustomed to eating rich in fiber foods, as well as those with intestinal diseases.