Cranberries offer promise for diabetics: Study

Sweetened dried cranberries with a reduced sugar and increased fibre content may benefit type-2 diabetics by delivering healthier glycemic and insulin responses, suggests a small study.

Consumption of the low-sugar high-fibre sweetened dried cranberries led to better glucose peaks and lower insulin peaks, with a peak insulin of 15, compared to 22 for both bread and sweetened cranberries, while raw cranberries produced a peak of 10.

Furthermore, blood sugar levels peaked at 158 minutes, compared to 175 minutes for both the bread and sweetened cranberries, and 127 minutes for raw cranberries.

The findings of the study, which involved only 13 diabetics, were reported earlier this year at the Experimental Biology conference by Ted Wilson from Winona State University. The meeting’s abstracts are published in the FASEB Journal.

The study was funded by cranberry giants Ocean Spray using the company’s new low-sugar sweetened cranberries,

Christina Khoo, PhD, Ocean Spray’s research sciences manager told NutraIngredients.com that the researchers are preparing a full paper for submission to a peer-reviewed journal. NutraIngredients.com has not seen the full data.

“The less sugar high fibre SDC was developed with the needs of the type-2 diabetic in mind,” said Khoo. This represents a large and growing market, with an estimated 19 million people affected by diabetes in the EU 25. This figure is projected to increase to 26 million by 2030.

Study details

Wilson and his co-workers recruited 13 type-2 diabetics and randomly assigned them to receive a single serving of white bread (57g, 160 calories, 1 g fibre), raw cranberries (55g, 21 calories, 1 g fibre), sweetened dried cranberries-original (40g, 138 calories, 2.1g fibre), or the low-sugar high-fibre sweetened cranberries (40g; 113 calories, 1.8g fibre plus 10g polydextrose).

The low-sugar sweetened dried cranberries were associated with a healthier glycemic and insulinemic response, than both white bread and the regular sweetened dried cranberries, said the researchers. The responses were second only to less palatable raw cranberries, they added.

“Fibre is component lacking in the diet of many diabetics,” said Khoo. “The added fibre in the SDC may slow absorption of glucose, helping regulate blood sugar. The combination of less sugar and high fibre could be of benefit to the type-2 diabetic, as our research has shown. SDCs are ideal to snack on throughout the day, either on their own or as a fruit inclusion in a variety of products such as bagels and muesli bars as part of a healthy, well balanced diet.”

Known and unknowns

Due to relative ‘newness’ of the low-sugar sweetened cranberries, the company and its researchers “haven’t had a chance to look at everything”, said Khoo, and no direct data was available to support the anti-adhesion or UTI-reducing potential of the ingredient.

She noted, however, that she would expect the same kind of results as that observed for the normal sweetened cranberries. A pilot study by Amy Howell from Rutgers University and co-workers from Harvard reported that the “sweetened dried cranberries may elicit bacterial anti-adhesion activity in human urine”, according to data in the Journal of Alternative and Complementary Medicine (Vol. 11, pp. 875-878).

Khoo said that she was hopeful for additional studies to examine the potential of the new product. “I am hoping we would initiate longer trials,” she said. “And we shouldn’t neglect the UTI component.”

Source: FASEB Journal

Experimental Biology Meeting Abstract, 2009, Volume 23: 900.6

“Glycemic response of type 2 diabetics to sweetened dried cranberries”

Authors: T Wilson, EF Morcomb, TP Schmidt, JL Luebke, EJ Carrell, MC Leveranz, L Kobs, AP Singh, N Vorsa, PJ Limburg