Asthma is a respiratory condition that causes serve constriction of the airways (specifical bronchi of the lungs). Individuals who are asthmatic experience hypersensitivity (overly sensitive) to certain allergens. While a normal non-asthmatic individual may only experience small inflammation from interaction with a specific allergen, the immune system of asthmatic patients overreacts, leading to inflammation/increased swelling and mucus build up in the airways, making it difficult to breathe.
A new study published on April 7th in the journal Immunology has taken this one step further and investigated the possible health benefits of keto for asthma and allergy sufferers.
Innate lymphoid cells (ILCs) play a major role in barrier immunity (a section of the innate immune system that is responsible for basic immune defense; barrier immune cells respond to pathogens but do not directly respond to infections). ILCs protect the lungs by releasing inflammatory cytokines and healing damaged mucus membranes (damaged membranes can increase susceptibility to infection and other problems). Inflammation is often seen as a bad thing, but in this case, these inflammatory cytokines are able to stimulate mucus-producing cells, to protect mucus that coats and protects the vulnerable membranes within the lungs. This is a normal process that helps protect against infection; however, individuals who are asthmatic experience a stronger than normal inflammatory response. The exaggerated inflammatory response leads to inflamed bronchi that reduce breathing capacity.
Professor Wilhelm, one of the lead investigators in this study, found that rodents on a ketogenic diet experienced a massive decrease in ILCs. He said “Normally, contact with allergens increases the number of ILCs in the bronchi fourfold. In our experimental animals, however, it remained almost unchanged. Both mucus production and other asthma symptoms decreased accordingly”. This was concluded to be a result of both limited fatty acid availability and glucose deficiency.