A team of Montreal doctors managed to fully reverse prediabetes in 40 per cent of patients, thanks to a diet free of ultra-processed foods and regular exercise.
According to a study published in January, physicians at the Montreal Heart Institute also managed to restore normal glucose levels in 20 per cent of people newly diagnosed with type II diabetes in six months.
“For a patient, living with pre-diabetes, reversing pre-diabetes to normal glycemia compared to patients that evolve to type II diabetes, when followed 20 years later, the number of cardiovascular events are reduced by 50 per cent,” said Josep Iglesies-Grau, preventive cardiologist at the Montreal Heart Institute and professor at Université de Montréal.
Dr. Iglesies-Grau said he and his team developed the program five years ago. Patients receive a customized plan of diet, nutrition and workouts as well as regular follow-ups for 12 months.
“What we normally propose to patients is to learn the Mediterranean diet,” Iglesies-Grau said.
“At the same time, we’re adding nowadays also a focus on ultra-processed foods, helping patients identify these foods, try to find replacements to these foods,” he added.
Dr. Iglesies-Grau said patients are also taught to build a habit of cooking at home and eating fresh and minimally processed foods.
Moderate intensity exercise of at least 30 minutes a day, five times a week, also plays an important role.
“We propose cardio,” Dr. Iglesies-Grau explained. “It can be walking, brisk walking, running, swimming, dancing, yoga.”
Claude Brillon completed the year-long program in March 2025. He enrolled after getting a prediabetic diagnosis while he was hospitalized following a stroke.
Brillon had considered himself as someone who ate well and worked out, but he learned to adapt his diet and exercise routine.
“I wasn’t eating enough vegetables (…) I was eating a bit too much fruit,” Brillon said, as he went on to describe how surprised he was to find out that excess fructose — a natural form of sugar — contained in fruits can at times lead to high blood sugar if taken in excess.
“I was not doing any strength exercise,” Brillon also mentioned.
“It was a fine tuning to my existing program and that fine tuning made the whole difference,” he said about how he began to undertake a new strength training regiment he hadn’t thought to do before.
Strength training is one of the exercise recommendations given to patients by the team, which they recommend at least twice a week.
“Increasing muscle mass and muscle function, those are two things that work best to reverse [prediabetes and type II diabetes],” said Dr. Iglesies-Grau.
Brillon is one of the many success stories of the 500 patients, including 200 seen so far this year, that have completed the program.
But, Iglesies-Grau says the priority should also be focused on prevention and not just treatment as rates of prediabetes and type II diabetes continue to rise in Canada. Diabetes is linked to higher risks of heart disease, high cholesterol and high blood pressure.
“Prevention is extremely important, particularly, nowadays that we’re seeing that our healthcare system is more a system to care for sick people,” Dr. Iglesies-Grau said. “We do not put enough resources, in my opinion, in prevention.”
According to Dr. Iglesies-Grau, there are a number of preventive measures that the government could implement to help reduce diseases before patients become officially diagnosed, which he said should begin with family physicians.
“Equipping family doctors with a team of dieticians and kinesiologists and all other services that can help patients,” he began to say.
Investing in schools and education where students are taught how to cook healthy meals from a young age, and encouraging active transport such as cycling, are among other measures he listed.
Not one to wait around for governmental support, the cardiologist says he and his team at the institute will continue their work with the aim to help as many patients as possible.
“We’re looking also for resources to improve and to find more dieticians that can be involved and more kinesiologists to offer these to more and more patients, and also being able to continue our research program to find newer and better and more personalized ways to help people reverse type II diabetes and prediabetes,” he said.
Those personalized ways include inviting family members to join appointments so that everyone in the household can be involved when it comes to preparing and eating healthy meals, and extending access to training programs.
“At the beginning training was just at the EPIC Centre,” Dr. Iglesies-Grau said. “Nowadays we’re open and we do tele-training or we propose programs for patients that they can do at their home or in the gym next to their home.”
