In a promising development for cat lovers struggling with allergies, farm-fresh eggs, particularly those from farms where chickens coexist with cats, could hold the antidote to feline-induced sneezing and wheezing. Research indicates that chickens raised in proximity to cats develop antibodies to Fel d 1, the protein in cat saliva responsible for up to 90% of allergic reactions in susceptible individuals.
Fel d 1, a sticky protein found on cat fur after grooming, has the ability to adhere to furniture and clothing. Furthermore, it is light and can easily travel through the air, leading to its presence in homes without cats, various buildings, and public transportation. H. James Wedner, MD, FACP, an allergy and immunology specialist at Washington University in St. Louis, emphasizes the ubiquity of this allergen, stating, “If you think about where you might find cat allergen, it’s all over the place.”
The breakthrough lies in chickens that develop an antibody to Fel d 1, known as IgY. These antibodies are then concentrated in the egg yolk. When these yolks are incorporated into a cat’s diet, it has the potential to reduce the cat’s allergenicity. A 2019 study funded by Nestlé Purina Research involving 105 cats on an IgY antibody diet demonstrated a decrease in the active Fel d 1 allergen in their hair after 12 weeks.
Building on this research, a proof-of-concept study in 2021, also sponsored by Purina and led by Wedner, involved 11 participants with a strong history of cat allergies. Placed in greenhouse chambers with blankets from cats fed eggs with IgY antibodies or a control diet, participants in chambers with cats on the egg product exhibited significantly fewer symptoms.
It is important to note that while eggs with IgY antibodies may reduce the Fel d 1 levels in cats, the study involved feeding the eggs to the cats, not humans. Humans do not produce the Fel d 1 protein, clarifies Kara Wada, MD, an allergist/immunologist at The Ohio State University Wexner Medical Center.
Looking ahead, scientists are exploring the use of CRISPR gene editing technology to create hypoallergenic cats by removing Fel d 1. Following the 2019 research, Purina introduced an anti-allergen cat food named LiveClear. However, it’s essential to acknowledge Purina’s vested interest in the product’s success, according to Wada.
For individuals seeking alternatives to mitigate cat allergies, Wada suggests keeping cats out of the bedroom, utilizing air purifiers, taking allergy medications, or opting for allergy vaccines. She emphasizes a multi-pronged approach for dealing with allergy-related inflammation, often yielding more success in treatment.