Previous studies on mice have suggested that the difficult diet can add 10 years to a human lifespan, even warding off Alzheimer's and cancer.
Other work has shown that infusing ketones directly into the bloodstream can reduce blood sugar levels.
This could be a key to diabetes patients whose bodies do not produce enough insulin to properly break down glucose, leading to spikes in their blood sugar levels, which, in turn, can cause heart attack, stroke and kidney failure.
Doctors advise people with diabetes to avoid carbs which break down into glucose – a sugar molecule – that they cannot convert into energy without insulin.
Keto diets consist of almost no carbs, focusing instead on protein and foods high in healthy fats, making them a good fit for people with diabetes.
Paradoxically, though diabetes is often associated with obesity, high fat intakes may be good for people suffering from the condition.
Keto diets are so-called because the foods allowed by them are high in fatty acids that get converted into ketones by the liver and act as an alternative energy source to glucose.
For the new study, the researchers wanted to see if a keto supplement, rather than the notoriously strict diet, could have the effects on people.
The researchers hoped that these raw, unadulterated forms of the compound, called ketone monoesters, which can be processed more immediately by the body, might raise blood ketone levels more dramatically.
They tested their supplement-infused drinks on healthy subjects, but "if the same responses were seen in people with, or at risk for, type 2 diabetes then it is possible that a ketone monoester supplement could be used to lower glucose levels and improve metabolic health," study co-author Dr Jonathan Little of the University of British Columbia said.
"We are working on these studies at the moment," he added.
Dr Little, along with colleagues at the University of Oxford, demonstrated a single drink enabled better control by reducing glucose spikes.
In the study, 20 volunteers twice consumed the supplement or a placebo after a 10-hour fast.
Then, half an hour later, they had a drink containing 75 grams of sugar, a standard glucose tolerance test.
Blood samples were collected every 15 to 30 minutes throughout the entire two and a half hour protocol for analyses of glucose, blood fats and hormones.
Compared to the placebo, the blood sugar spike was reduced on the day that the individuals had consumed the ketone drink.
The researchers pointed out the study was carried out with healthy young individuals to reduce the confounding factors of insulin resistance, dysfunction of beta cells in the pancreas that produce the glucose controlling hormone and medications.
But Dr Little said it offers hope of a better treatment for type 2 diabetes, the form linked to obesity which affects more than 3.5 million people in the UK alone.
He added: "The ketone supplements do not taste very good and, in order to blind the participants, we had to make a control drink that also tasted distinctly bad.
"It made for interesting mornings seeing how the participants would respond to the taste of their drinks!"
Adverse effects of the diet include impaired growth, which can be caused by a nutrient deficiency, as well as an increased risk of getting kidney stones.
