ACS: In an era when the label “natural” hits a sweet spot with consumers,
some uncommon sugars emerging on the market could live up to the
connotation. Preliminary animal studies have suggested that allulose and
other low-calorie, natural rare sugars could help regulate glucose
levels. Now, researchers are investigating how they might exert such
effects. They report their findings in ACS’ Journal of Agricultural and Food Chemistry.
Sucrose is the natural sweetener most labels refer to when sugar is
on the ingredient list. It’s abundant, and manufacturers figured out
long ago how to extract it on a large scale from sugar cane and other
sources. Allulose, which is 70 percent as sweet as sucrose, and other
rare sugars also can be found in fruits and vegetables but in very small
amounts. Recently, however, researchers discovered an industrial way to
produce allulose in large quantities from high-fructose corn syrup,
which contains about equal parts glucose and fructose. Some studies have
suggested that allulose can help control weight gain and glucose
levels, but no one knew why. Tomoya Shintani and colleagues wanted to
confirm that allulose — and potentially other rare sugars — yield these
results and to take a step toward understanding why.
To investigate, the team of scientists gave three groups of rats
plain water, water with high-fructose corn syrup and water with
rare-sugar syrup (RSS) containing glucose, fructose, allulose and other
rare sugars for 10 weeks. The rats drinking RSS-infused water gained
less weight, had less abdominal fat, and had lower blood glucose and
insulin levels compared to the high-fructose corn syrup group. The study
also showed that the liver cells’ nuclei in the RSS rats exported to
the cytoplasm higher amounts of glucokinase, an enzyme that reduces
blood-sugar levels by helping convert glucose to its stored form,
glycogen. Although further testing is needed, the researchers say, the
findings suggest that rare sugars could be a good alternative sweetener.
The authors acknowledge funding from the Matsutani Chemical Industry Co. and Meijo University.