Dogs are known as man's best friend and their strong sense of smell means they also have the potential to save lives - detecting changes in blood glucose amounts in type 1 diabetes patients and urine samples from those with prostate cancer.
Magic leaps up, billeting his paws on his owner's knees, his brown eyes staring into hers.
It is a routine he has done thousands of times.
Magic is a medical alert help dog and has been trained to detect a minute shift in the blood sugar levels of his owner, Claire Pesterfield.
Using his better sense of smell, he is capable of detecting tiny odor concentrations, around one part per trillion, that enable him to alert Claire to when she needs to inject herself with insulin.
Without Magic's assistance, changes in her blood, levels could put her at risk of an attack, or - in extreme cases - the onset of a coma.
Claire has type 1 diabetes, but - unlike most people with the situation - her body does not display the warning signs that a dangerous episode might be about to occur.
In the three and a half years, the dog has alerted and potentially saved my life 3,500 times. And he does it all for a dog biscuit.
Claire works as a children's diabetes nurse, supporting and educating children with type 1 diabetes and their families.
Claire says she would not be able to do the job were it not for Magic, as she would be at risk of collapsing mid-meeting.
"Without him I would be testing my blood glucose level every 20 or 30 minutes, to try and prevent what was going to happen," she explains.
Having Magic also sends the message to the children she works with, she adds, that, "You can still live life to the full when you've got diabetes."
When he detects an alternation in her blood glucose level, he prods her with his paw to wake her up.
NHS trials are currently estimating if dogs could also be used to detect prostate cancer.
The research being organized offers an opportunity for the disease to be detected at an early stage - vital for improving survival rates.
The dogs - usually from the gundog species, such as labradors and springer spaniels - are taught to detect a sample of urine from a patient with prostate cancer.
It is thought that the dogs can pick up the odor of cancer "volatiles", which travel from the infected cells into the urine as the body tries to dispose of the chemicals.
When they correctly detect a sample containing this volatiles, they are given a treat as positive reinforcement.
The dog's performances are write downed, and those that make the grade have more than a 90% success rate at detecting a sample from a patient with prostate cancer.
The dogs are people's best friends, we saw this once again.