How the keto diet works
The ketogenic, or keto diet, is an extremely low-carb diet in which carbs are reduced to less than 10% of the total daily food intake, replaced mainly by lean meats and fresh fruits and vegetables.2 When the glucose normally found in carbs is eliminated, the body must find another source of fuel, so it will instead begin burning fat. This will show up as ketones in your urine even if you’re not diabetic.
The liver converts this fat into ketones, which become the body’s alternate food source. Because the body requires so much of an increase in fat to serve as this fuel, the keto diet increases fat intake to anywhere from 70% to 90% of total consumption for a 2,000 calorie per day diet.2,3
Asthma and the inflammatory response
Acute inflammation of the respiratory tract in response to an irritant, such as an allergen, is actually an important part of the body’s natural immune system. As part of this response, a special group of cells, called innate lymphoid cells, helps increase mucus production to expel harmful substances or pathogens from the bronchial tubes.
For otherwise healthy subjects, mucus production then decreases, once the threat has been eliminated. In the case of those with asthma, however, the innate lymphoid cells do not turn off mucus production, so the inflammatory process becomes chronic. This can then lead to inflamed bronchial tubes and breathing difficulties normally associated with chronic asthma.
Allergy-induced asthma and slowing inflammation
A recent study in the journal Immunity used mice examined the effect of a Ketogenic diet on inflammation of the respiratory tract, following exposure to an allergen.4
Because the innate lymphoid cells rapidly multiply, the researchers’ goal was to slow down their division, which should also slow the chronic inflammatory process. They found that fatty acids were required to help form the innate lymphoid cells, so fed mice bred to be asthmatic a keto diet and then exposed them to an allergen.
Because the mice were on this diet, fatty acids were diverted away from building innate lymphoid cells to instead be converted into ketones. With fewer innate lymphoid cells available, the inflammatory process in the lungs dramatically slowed down.4
Given concerns over COVID, it is only natural for your patients with chronic asthma to be concerned. They may find that a keto diet can not only help them lose weight, but might also reduce some of the respiratory symptoms associated with chronic asthma attacks.