Salt Intake Is Related to Soft Drink Consumption
in Children and Adolescents
A Link to Obesity?
Feng J. He, Naomi M. Marrero, Graham A. MacGregor
Abstract—Dietary salt is a major determinant of fluid intake in adults; however, little is known about this relationship in
children. Sugar-sweetened soft drink consumption is related to childhood obesity, but it is unclear whether there is a link
between salt and sugar-sweetened soft drink consumption. We analyzed the data of a cross-sectional study, the National
Diet and Nutrition Survey for young people in Great Britain. Salt intake and fluid intake were assessed in 1688
participants aged 4 to 18 years, using a 7-day dietary record. There was a significant association between salt intake and
total fluid, as well as sugar-sweetened soft drink consumption (P?0.001), after adjusting for potential confounding
factors. A difference of 1 g/d in salt intake was associated with a difference of 100 and 27 g/d in total fluid and
sugar-sweetened soft drink consumption, respectively. These results, in conjunction with other evidence, particularly
that from experimental studies where only salt intake was changed, demonstrate that salt is a major determinant of fluid
and sugar-sweetened soft drink consumption during childhood. If salt intake in children in the United Kingdom was
reduced by half (mean decrease: 3 g/d), there would be an average reduction of ?2.3 sugar-sweetened soft drinks per
week per child. A reduction in salt intake could, therefore, play a role in helping to reduce childhood obesity through
its effect on sugar-sweetened soft drink consumption. This would have a beneficial effect on preventing cardiovascular
disease independent of and additive to the effect of salt reduction on blood pressure. (Hypertension. 2008;51:629-634.)
Key Words: salt intake ? soft drink consumption ? obesity ? children and adolescents
vational epidemiological studies and controlled trials where
salt intake was altered.1,2It has been estimated that reducing
salt intake by half, eg, from the current intake of ?10 g/d to
the World Health Organization recommended level of 5 g/d,
would reduce fluid intake by ?350 mL/d per person.1
However, there are no studies in children that have looked at
the relationship between salt intake and fluid consumption.
In nearly all of the developed and many developing countries,
childhood obesity and subsequent diabetes are major public
health problems.3Intervention strategies, eg, changing diet and
increasing physical activity levels, could reduce obesity. How-
ever, few have been proven to be effective,4,5and, indeed, in
most countries the prevalence of obesity is rapidly increasing.3
Some studies have also highlighted the difficulty of changing
diet and lifestyles in young individuals.6
Sugar-sweetened soft drink consumption is an important
source of calorie intake in children and is also claimed not to
give rise to any feeling of satiety and is, therefore, linked to
obesity.7In adults, it has been shown that a reduction in salt
intake reduces fluid intake1and would lead to a concomitant
reduction in soft drink consumption. In children, sugar-
n adults, the quantitative relationship between salt intake
and fluid consumption is well documented by both obser-
sweetened soft drinks are an important component of total fluid
intake. A reduction in salt intake might, therefore, be important
in reducing sugar-sweetened soft drink consumption and, thus
reducing childhood obesity. Compared with other diet and
lifestyle changes, a modest reduction in salt intake is easier to
make as, in most developed countries, ?80% of salt intake now
comes from salt hidden in food8and can be done by slow but
progressive reductions in the amount of salt added to food by the
food industry without necessarily informing the consumers.
Such a policy has been adopted in the United Kingdom, and a
recent study has shown that salt intake has already been reduced
as a result of this strategy and, importantly, without consumers
having to change what they eat.9
To study the relationship between salt intake and total fluid
consumption, as well as the consumption of sugar-sweetened
soft drinks, we analyzed the data from a large cross-sectional
study, the National Diet and Nutrition Survey for young
people in Great Britain, which was carried out in 1997 in a
nationally representative sample of individuals aged between
4 and 18 years.10
We obtained the data of the National Diet and Nutrition Survey for
young people from the United Kingdom Data Archive.11The
Received September 5, 2007; first decision September 26, 2007; revision accepted December 4, 2007.
From the Blood Pressure Unit, Cardiac and Vascular Sciences, St George’s, University of London, London, United Kingdom.
Correspondence to Feng J. He, Blood Pressure Unit, Cardiac and Vascular Sciences, St George’s, University of London, Cranmer Terrace, London,
SW17 0RE, United Kingdom. E-mail firstname.lastname@example.org
© 2008 American Heart Association, Inc.
Hypertension is available at http://hyper.ahajournals.orgDOI: 10.1161/HYPERTENSIONAHA.107.100990
Salt Intake, Hypertension, and Obesity in Children
their food products for purely commercial reasons, one of
which is to protect soft drink sales, because some soft drink
companies own large snack companies that specialize in
highly salted snacks. However, they should not be allowed to
stand in the way of a reduction in salt intake, because this
reduction would have major benefits to the health of the
whole population and, particularly, to children in potentially
preventing the development of high blood pressure and
obesity, thereby reducing the appalling burden of cardiovas-
cular disease later in life.
Our analysis of the data from the National Diet and Nutrition
Survey for young people shows that, in a free-living popula-
tion of British children and adolescents, differences in salt
intake are associated with differences in total fluid, as well as
sugar-sweetened soft drink consumption. Our results, in
conjunction with other evidence, particularly that from ex-
perimental studies where only salt intake was changed,1
demonstrate that salt intake is an important determinant of
fluid and sugar-sweetened soft drink consumption during
childhood. Currently, in most countries, salt intake in young
people is unnecessarily high due to hidden salt added to food
by the food industry.8A modest reduction in salt intake has
been shown to cause a fall in blood pressure in children.22
According to our present analysis, it would also reduce
sugar-sweetened soft drink consumption and, therefore, play
an important role in helping to reduce childhood obesity and
diabetes. This would have a beneficial effect on preventing
cardiovascular disease independent of and additive to the
effect of salt reduction on blood pressure.
We thank the original data creators, depositors, copyright holders,
the funders of the Data Collections, and the United Kingdom Data
Archive (University of Essex, Colchester, United Kingdom) for the
use of data from the National Diet and Nutrition Survey on young
people aged 4 to 18 years. They bear no responsibility for the current
analysis or interpretation of the results.
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