Carbohydrates and Health

Preface
Dietary carbohydrates and their role in health were last considered by the Committee
on the Medical Aspects of Food Policy in reports published in the 1980s and 1990s.
Since then, considerable evidence has emerged on the role of carbohydrates in cardiometabolic,
colo-rectal and oral health. The present report details the evidence SACN has
considered and the approach SACN has taken to reviewing the relationships between
dietary carbohydrates and health. The evidence was assessed using the SACN Framework
for the Evaluation of Evidence and graded according to a system developed specifically
for this review. SACN commissioned systematic reviews of the evidence on cardiometabolic,
colo-rectal and oral health to inform this report and this is the first time
the committee has taken that approach. The findings of the systematic reviews have
been used to inform the very detailed main body of the text which thereby provides
a comprehensive and transparent account of the evidence and how SACN drew its
conclusions.
As a result of its deliberations, SACN is now recommending that a new definition of
dietary fibre be adopted in the UK and that a definition of ‘free sugars’ be used in
nutrition advice in place of ‘non-milk extrinsic sugars’. Following careful consideration
of the evidence, SACN is also recommending that the dietary reference value for
carbohydrates be maintained at a population average of approximately 50% of total
dietary energy intake and that the dietary reference value for dietary fibre for adults
should be increased to 30g/day. Furthermore, SACN is recommending that population
average intake of free sugars should not exceed 5% of total dietary energy. This advice,
that people’s intake of ‘free sugars’ should be lower than that currently recommended
for non-milk extrinsic sugars, is based on SACN’s assessment of evidence on the effect of
free sugars on the risk of dental caries and on total energy intake. A higher sugars intake
increases the risk of higher energy intakes - the higher the consumption of sugars, the
more likely people are to exceed their estimated average requirement (EAR) for energy.
Therefore, if intakes of free sugars are lowered, the more likely it is that the EAR for
energy will not be exceeded, and this could go some way to addressing the significant
public health problem of obesity.
I would like to thank those who provided comments on the draft version of this report
during the public consultation. All the comments were carefully considered before the
report was finalised. The process assisted the Committee in refining the text and its
approach to making recommendations.
This has been a challenging and large undertaking for SACN and I would like to thank
the Carbohydrates Working Group, particularly the Chair, Professor Ian Macdonald, and
the Secretariat for their great commitment in producing this report. Particular thanks
also go to those in the Nutritional Epidemiology Group at the University of Leeds who
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