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How much sugar is bad for us? Does the form of sugar (for example, added sugar in some fruit juices, glucose found in fruit, or fructose found in some vegetables) matter? The health impact of sugars—which also include sucrose, maltose, and lactose—is something consumers and healthcare professionals have been talking about for a long time. For Diabetes Canada, this is an important issue, given evidence about the negative effects added sugars have on people at risk of or living with type 2 diabetes.

For Dr. John Sievenpiper, a 50-year-old physician and scientist based in Toronto, it is a question he is determined to answer—and one he has dedicated much of his research to finding out. “My undergraduate degree is in nutrition but I really fell in love with research during my graduate training, where I focused mostly on diabetes and blood sugar control,” he says. “Now I study different types of sugars and counsel patients on diet-linked health problems such as obesity, diabetes, and heart disease.”

With a passion for all things food- and diabetes-related, Sievenpiper played a key part in helping update the nutrition chapter of the Diabetes Canada 2018 Clinical Practice Guidelines for the Prevention and Management of Diabetes in Canada (Guidelines)—a series of recommendations, based on the latest research, that help physicians and other healthcare providers provide the best care to their patients. He is co-leading the committee that will revise that information for the next version of the Guidelines.

“Early on, I had an interest in developing guidelines to see how the work we’re doing as researchers is having an impact on patients at the bedside,” says Sievenpiper. “With the Guidelines, it used to be about quantity— ‘low fat,’ ‘high carb,’ ‘high protein,’ etc. Now we’re focusing more on food and dietary pattern-based approaches, such as vegetarian or Mediterranean diets.”

In his latest study, funded by Diabetes Canada, Sievenpiper is looking at how major sources of sugars found in food, in particular those containing fructose (a commonly used sugar), affect an individual’s risk factors for developing heart disease or diabetes, such as weight, blood glucose (sugar), blood pressure, and blood lipids (fats). While concerns about sugar-sweetened beverages in people with diabetes seem to be warranted, early study results show that the effect of other major food sources of sugars (such as cereals, yogurt, and fruit) is less clear.

You can’t define healthy foods by a single nutrient like sugar. It’s also about the overall diet we consume and the lifestyle we live.

Sievenpiper is trying to determine whether the form of sugar matters and whether any adverse effects relate more to excess calories than to the sugars themselves.

“There is a misconception out there that all sources of dietary sugars are the cause of diabetes,” he says. “While we certainly shouldn’t over-consume sugars, we have to start talking about healthy foods as opposed to specific nutrients.”

With the support of Diabetes Canada and the Canadian Institute of Health Research, his team is also looking at dietary pulses—foods like chickpeas, dried peas, and lentils—in terms of their positive health impact on people with diabetes. “We expect our research will further shape clinical guidelines and health policy development in the future,” says Sievenpiper. “In terms of chronic diseases, diabetes is one of the most preventable and treatable, so we have a huge role to play in helping to improve outcomes.”

“Dr. Sievenpiper is making contributions to the field of nutrition that are real game changers,” says Dr. Jan Hux, past president and CEO of Diabetes Canada. “He is studying fundamental questions, such as how the source and form of sugars in our diets relate to their health impacts.” She says that he also brings a “refreshingly practical focus” to the fact that people eat “food” rather than “nutrients,” and that high-lighting positive dietary patterns, such as a Mediterranean or vegetarian diet, may be more helpful than demonizing an individual food component, such as fructose.

Sievenpiper adds, “We can certainly learn from other countries and what other people are eating to find ways to translate our own eating guidelines toward healthier options.”

Dr. Sievenpiper at a glance

• Awarded Canadian Nutrition Society (CNS) Young Investigator Award for Outstanding Research (2019)

• Awarded Banting & Best Diabetes Centre Sun Life Financial New Investigator Award for Diabetes Research (2016-2018)

• Received CDA’s Clinician Scientist of the Year award (2015-2020)

• Appointed associate professor, Faculty of Medicine, University of Toronto (2015)

• Appointed staff physician, Department of Medicine, St. Michael’s Hospital (2014)

• Completed residency training in Medical Biochemistry, McMaster University, Hamilton, Ont. (2014)

• Formed the Toronto 3D Knowledge Synthesis and Clinical Trials Unit at St. Michael’s Hospital (2009)

•  Earned MD, St. Matthew’s University School of Medicine, British West Indies (2008)

• Earned PhD in Nutritional Sciences, University of Toronto (2004)

The last word

“There is no one best diet for diabetes, because it’s about individualizing nutrition. There are a number of good diets out there depending on one’s values and preferences.” –John Sievenpiper, physician and researcher

Did you know?

Diabetes Canada recommends that Canadians limit their intake of “free sugars” to less than 10 per cent of total daily calories. (Free sugar is any sugar that is added to foods, as well as sugars naturally present in honey, syrups, and fruit juices. It does not include sugar naturally present in milk or whole fruit and vegetables.) Based on a consumption of 2,000 calories per day, that would translate to about 12 teaspoons of free sugars. Twelve teaspoons may sound like a lot—but consider that one can (355 mL) of fruit juice or soda can have 10 teaspoons of sugar. To learn more, visit A New Way to Look at Your Plate.

Visit Research to read about the research projects and awards funded by Diabetes Canada.

How can you help us fund research that changes lives? Donate now!

(This article appeared in Diabetes Dialogue, Spring 2016)

Author: Rosalind Stefanac

Category Tags: Research;

Region: National

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