While researchers already knew that
drinks with added sugar could increase
a person's risk of type 2 diabetes, a new
study suggests that the same may be
true for naturally sweet drinks, such as
100% fruit juices, as well as artificially
sweetened beverages, such as "diet" soft

A new study suggests that even 100% natural fruit
juices may increase the risk of diabetes.

Research has shown that drinking soft drinks with
added sugar can increase a person's risk of
developing type 2 diabetes by affecting subtle
metabolic mechanisms .

But are "diet" soda and 100% fruit juices that
contain a natural level of fructose but no added
sugar any healthier?

The evidence surrounding diet soda and its effect
on diabetes risk has been conflicting. Some studies
suggest that it might have an impact, while others
report that there is no association between the two.

Most people believe that naturally sweet drinks are
healthful. However, recent research has shown that
they are not nearly as good for us as we think. One
study that we covered on Medical News Today in
July this year, for instance, indicated that they could
increase a person's risk of cancer.

Now, research from an international team of
investigators from Harvard T. H. Chan School of
Public Health in Boston, MA and Fudan University
in Shanghai, China, suggests that all sugary drinks,
including natural fruit juices and artificially
sweetened beverages, could increase diabetes risk.

However, the study, which appears in the journal
Diabetes Care, also offers some hope. It notes that
people can decrease this risk by replacing sugary
drinks of any kind with non-sweetened beverages,
such as water, tea, and coffee .

Sugary drinks linked to 16%
increase in risk
Drouin-Chartier and colleagues analyzed data
collected over 22–26 years from 76,531 women
enrolled in the Nurses' Health Study between 1986–
2012, 81,597 women enrolled in the Nurses' Health
Study II between 1991–2013, and 34,224 men from
the Health Professionals' Follow-up Study , enrolled
between 1986–2012.

The researchers gave the participants questionnaires
that asked them how often they consumed certain
foods and beverages. By analyzing the results, the
study authors found out how often participants
drank certain sugary drinks and were able to
calculate any changes in their drink consumption

The researchers found that people who increased
their total intake of soft drinks with added sugars
and naturally sweet fruit drinks by over 4 ounces
(oz) per day over 4 years saw an associated
diabetes risk increase of 16% over the following 4

However, those who increased their total intake of
artificially sweetened beverages — such as diet
soda — by the same quantity over the same period
saw an associated 18% increase in the risk of
developing type 2 diabetes.

These associations remained in place even after the
researchers adjusted for confounding variables,
including body mass index ( BMI ), different dietary
changes, and relevant lifestyle habits.

The investigators caution, however, that the finding
regarding artificially sweetened beverages may be
unreliable because it remains unclear which way the
association runs. They explain that people who
know that they are already at high risk of
developing diabetes may switch from sugary drinks
to diet sodas to try and mitigate that risk.

Moreover, the study authors also point out the risk
of surveillance bias in their research. This refers to
the fact that people who are at high risk of
developing diabetes are more likely to undergo
screenings for diabetes, therefore receiving a
diagnosis sooner than other individuals.

Overall, the research suggests that people might
want to consider caution about their intake of sweet
drinks of all kinds. It also found that switching to
unsweetened drinks could help reduce diabetes

More specifically, replacing one daily serving of a
sweet drink with water or unsweetened coffee or
tea was associated with a 2–10% lower risk of
type 2 diabetes.

"The study results are in line with current
recommendations to replace sugary beverages with
noncaloric beverages free of artificial sweeteners,"
notes senior author Prof. Frank Hu, from Harvard
T.H. Chan School of Public Health.

Nor should people overestimate the benefits of
natural juices. "Although fruit juices contain some
nutrients, their consumption should be moderated,"
he stresses.