There is increasing scientific evidence that
low-calorie artificial sweeteners promote metabolic
dysfunction, and large consumption of these sugar
substitutes could promote fat accumulation,
especially in people who are already obese,
preliminary research suggests.
“Many health-conscious individuals like to consume
low-calorie sweeteners as an alternative to sugar.
However, there is increasing scientific evidence
that these sweeteners promote metabolic
dysfunction,” said Sabyasachi Sen, M.D., an
Associate Professor of Medicine and Endocrinology at
George Washington University in Washington, D.C.,
and the study’s principal investigator.
Sen and his colleagues tested sucralose, a popular
low-calorie sweetener, on stem cells—cells that
could change into mature fat, muscle, cartilage or
bone cells—taken from human fat tissue.
They placed these cells in Petri dishes for 12 days
in media that promotes fat production.
At a 0.2-millimolar sucralose dose similar to the
concentration found in the blood of people with high
consumption of low-calorie sweeteners—equal to four
cans of diet soda per day—the researchers said they
observed increased expression of genes that are
markers of fat production and inflammation.
There also was increased accumulation of fat
droplets in cells, particularly at a larger dose (1
millimolar), Sen reported.
With this evidence, the investigators then conducted
a separate experiment.
They analyzed biopsy samples of abdominal fat
obtained from eight subjects who said they consumed
low-calorie sweeteners (mainly sucralose and a trace
of aspartame, and/or acesulfame potassium).
Four of the subjects were healthy weight, and four
According to Sen, they saw evidence of increased
glucose (sugar) transport into cells and
overexpression of known fat-producing genes,
compared with fat biopsy samples from subjects who
did not consume low-calorie sweeteners.
Additionally, he noted that subjects who consumed
low-calorie sweeteners, which are several-fold
sweeter than sugar, showed an overexpression of
sweet taste receptors in their fat tissue; this
overexpression was up to 2.5-fold higher than in
subjects without history of consumption of these
Overexpression of sweet taste receptors in the
abdominal fat, he said, may play a role in allowing
glucose to enter cells, from which the body absorbs
it into the bloodstream.
All these findings are signs of metabolic
dysregulation in which the cellular mechanisms are
changing to make more fat, he explained.
Of concern, Sen said, these effects were most
apparent in the obese individuals who consumed
low-calorie sweeteners, rather than individuals of
He added that the observed increased uptake of
glucose into the cells is also concerning for
consumers who have diabetes and prediabetes, “who
already have more sugar in their blood,” compared to
their counterparts who do not have diabetes.
More studies are necessary in larger numbers of
people with diabetes and obesity to confirm these
findings, he stressed.
“However, from our study,” Sen stated, “we believe
that low-calorie sweeteners promote additional fat
formation by allowing more glucose to enter the
cells, and promotes inflammation, which may be more
detrimental in obese individuals.”
For more information
The Endocrine Society