Diabetes Alert Dogs: How Do They Do It?
By Jacqueline Marshall, Mar 20, 2014
Diabetes alert dogs are trained to warn diabetics when their blood sugar levels are changing, giving them time to make adjustments before it’s too late.
Alert dogs learn to detect shifts in our glucose using their sense of smell. Having up to 300 million scent glands, they can distinguish subtle alterations in human body odors that scientists call volatile organic compounds, or VOCs.
What Alert Dogs Smell
VOCs are partly a signature blend of chemicals emitted by the bacteria living within us and on our skin. Our personal VOC scent also includes compounds thrown off when molecules in our body break down to create energy. We leak these odors into the air through our breath and skin.
Changes in a person’s blood sugar level alters his or her VOCs. It is these VOC changes that dogs can be trained to detect – and the training is rigorous. Although dogs have noses that know VOCs, they must learn to distinguish the smell of past and present VOC variations, and to notice the glucose changes in a variety of environments.
Alert Dog Training
A dog in diabetes alert training first undergoes scent discrimination lessons. They learn what hypoglycemia (low blood sugar) smells like and must discern it from other competing, and sometimes enticing, odors in the air.
Once they have basic scent detection down, dogs master more advanced skills:
- People with diabetes carry the smell of earlier hypoglycemic episodes on their clothing, carpeting, and furnishings. Alert dogs need to distinguish the “dead” scent of previous episodes from the smell of an occurring episode.
- Because assistance dogs can accompany their human anywhere, the dogs must also be able to pickup the hypoglycemic scent in a variety of environments – each a riot of interesting odors. For instance, they must recognize the hypoglycemic VOCs in places of employment, schools, public areas, cars, or other modes of transportation.
Diabetes alert dogs are usually paired with individuals diagnosed with type 1 diabetes, or severe type 2 diabetes. These canines have saved their diabetic humans many trips to the hospital, and this service grants people increased independence and confidence.
The Future: Artificial VOC Intelligence
Some VOC researchers have a goal of creating electronic VOC detectors that can diagnose and monitor diseases. People with diabetes may someday carry a “portable electronic nose” that detects the scent of their blood glucose and alerts them to changes requiring attention.
While an electronic glucose sniffer will be convenient, it can never replace all the intangibles that an alert dog provides its human – a dog’s unconditional affection is priceless. However, for those who do not want, or cannot manage, the expense and responsibility of dog-care, portable VOC detectors will no doubt be welcome.
Photo credit: John Nyboer