Breanne Harris, 25, first encountered a diabetes alert dog when she was a counselor at a camp for children with diabetes. Two people from Dogs4Diabetics, Inc., (D4D) — a nonprofit organization that trains assistance dogs to detect hypoglycemia in people with diabetes — brought an alert-dog-in-training to camp. Every night, the counselors would make midnight rounds to check campers’ blood glucose levels. In the dormitory, the dog tore free from the trainer, ran to one teenager, jumped on the bed, and tried to awaken the girl. “We checked her blood sugar immediately, and her sugar was 32 mg/dl, which is severely low,” says Harris, who has lived with Type 1 diabetes since she was 4. “I was sold at that point and applied for a dog.”
Kristen Beard, 24, who also has Type 1 diabetes, got a golden retriever puppy named Montana when she was about 19. One night Montana would not leave her alone as she slept. “He was crying and pawing at me. I was mad because he woke me up, but once I became aware, I thought maybe I should test my blood sugar. I tested it, and it was low,” Beard says. “I thought it was a fluke, but he started doing it regularly.” Now he wakes her at least twice a month to warn about her falling blood glucose. “He just started doing it on his own, and I reinforce the behavior with treats,” she says.
Veterinarian Nicholas Dodman recalls a client who had a German shepherd that was afraid of men, including the woman’s husband. The dog would avoid him even if they were in the same room. But one night, the dog woke him. The man realized that his wife, who had diabetes, was becoming hypoglycemic. After that, if the woman’s blood glucose dropped dangerously low, the dog would overcome his fear and wake up the man to help her.
“It was the only time he would go near the man,” says Dr. Dodman, professor and program director of the animal behavior department at Tufts University Cummings School of Veterinary Medicine in Massachusetts. “He saved her life several times over.”
Diabetes alert dogs, which warn people with diabetes when their blood glucose reaches dangerously low levels, are relative newcomers to the assistance dog scene, but they are making a real difference. In Beard’s case, a dog enabled her to live independently for the first time in her life. “Diabetes was a huge strain on my friends and my family before I got the dog,” says Beard, who has been living with diabetes since she was 7.
How do they do it?
The obvious question that everyone asks is how a dog can tell when a person is hypoglycemic, or has low blood glucose. The answer: They probably smell it.
“With its superior sense of smell and good ability to read body language, a dog can be taught to react to different situations,” says Dr. Dodman, the author of several books on animal behavior, including If Only They Could Speak (W.W. Norton & Co., 2002). “A diabetes alert dog picks up on an odor, and he is trained when this particular smell is around to alert his owners, because he will get a food treat.”
When a person has hypoglycemia, there is not enough glucose to make his brain function properly, so the body releases chemicals to raise blood glucose levels. If the body cannot raise the blood glucose level on its own, the person may become confused, pass out, have a seizure, or even die. Doctors usually recommend treating for hypoglycemia when a person’s blood glucose level falls below 70 mg/dl.
Among the chemicals the body releases in response to hypoglycemia are ketones. And just as narcotics dogs can smell drugs and search and rescue dogs can smell bodies, diabetes alert dogs appear to be able to recognize the unique odor of ketones, as well as of other chemicals released by the body.
“As your blood sugar starts to change, your biochemistry starts to change as well, and that biochemistry change releases a scent that they can pick up,” says Harris, who now works for D4D in California, where she got her alert dog, Destiny.