THE FACTS Cats, love them or hate them, are among the most common causes of allergies, affecting twice as many Americans as dogs do.

The sources of these allergies are proteins found in feline dander, urine and saliva, making all cats capable of provoking reactions. But some scientists suspect that the darker a cat’s coat, the greater the likelihood of it inducing allergic reactions.

Scientists showed this in a small study in 2000, involving 300 patients with allergies. They found that people with dark-colored cats were two to four times as likely to have moderate to severe symptoms as those who either owned cats with lighter coats or did not own a cat. Additional studies found that female cats produce less animal allergen than male cats.

Image Credit... Christoph Niemann

But the color association is not conclusive, said Dr. Clifford W. Bassett of Allergy and Asthma Care of New York, an author of the study. A later study in The Journal of Allergy and Clinical Immunology found that the color of a cat’s coat had no effect on how much allergen it produced. And Dr. Bassett said he and a colleague were planning a larger study to see if the earlier findings bear out.