Fruit and other foods high in fructose do not appear to have a detrimental effect on blood glucose levels; however, sugary drinks and some other foods that add "low-nutrient" excess energy to diets can have detrimental effects.
"These findings may help reorient dietary recommendations for fructose in the prevention and treatment of diabetes," said John Sievenpiper, lead author of the study and a specialist in clinical nutrition at St. Michael's Hospital in Toronto, Canada. .
The role of sugars in the development of diabetes and heart disease raises a wide debate and there is increasing evidence suggesting that fructose can be particularly harmful to health.
Fructose is produced naturally in a variety of foods – raw fruits and vegetables, natural fruit juices and honey.
It is also added to foods such as soft drinks, breakfast cereals, processed products, pastries and desserts that we consume as free sugars.
Dietary guidelines recommend reducing free sugars, especially fructose in sweetened beverages, but it is unclear whether for all food sources of these sugars.
The researchers analyzed the results of 155 studies that evaluated the effect of different dietary sources of fructose sugars on blood glucose levels in people with and without diabetes who were monitored for 12 weeks.
And the results show that most foods that contain fructose sugars do not have a detrimental effect on blood glucose levels when these foods do not provide excess calories.
Poor in nutrients
When a specific food analysis was performed, it was observed that fruits and fruit juices when these foods do not provide excess calories can have beneficial effects on glycemia and insulin control, especially in people with diabetes, while foods that add an excess of "nutrient-poor" energy to the diet, especially sugary drinks and fruit juices, appear to have detrimental effects.
The researchers conclude: "Until more information is available, health care professionals should be aware that the harmful effects of fructose sugars on blood glucose appear to be mediated by the source of energy and food."