Draft Carbohydrates and Health report
Scientific consultation: 26 June to 1 September 2014
Professor Ian Macdonald,
Chair of SACN CHO Working Group
The carbohydrate working group’s terms of reference
were:
• To review the evidence on dietary carbohydrate and
colorectal health (colorectal cancer, bowel function, constipation);
cardio-metabolic health (CVD, type 2 diabetes and obesity);
oral health.
• To review the terminology, classification and definitions of types
of carbohydrates in the diet.
• To review current dietary reference values (DRVs).
REVIEW METHODOLOGY
Evidence only from prospective studies & RCTs
3 systematic reviews
update search
WG considered evidence and drew conclusions
using an agreed grading system
Used conclusions to inform DRVs and
definitions of carbohydrates
Evidence base
• Only prospective cohorts and RCTs
• No ecological or cross-sectional studies
• Study duration:
– ≥6 weeks RCT
– ≥ 1 year for RCTs on weight outcomes
– ≥3 years cohort studies
– Colorectal health: no limit on study duration
• In healthy subjects (without overt chronic disease)
• Over 600 publications included in this assessment
Review process for the
carbohydrate report
WG considered evidence & prepared
report
SACN main committee
considered report
Public consultation
Report revised following consultation
Report signed off by SACN
Chair & main committee
Now
SACN’s draft recommendations: carbohydrate
The DRVs for total carbohydrate, free sugars, starch and
sugars contained within the cellular structure of food, and
milk sugars are proposed in the context of an energy intake
which is appropriate to maintain a healthy weight.
• The dietary reference value (DRV) for total carbohydrate
should be maintained at a population average of
approximately 50% dietary energy.
Total Carbohydrate Evidence
• No consistent effect of total CHO on blood
lipids
• No association of total CHO intake and risk of
T2DM
• Higher CHO, lower fat diets more effective
than lower CHO, higher fat at reducing BMI
and weight when energy restricted
• No association of total CHO intake and energy
intake
SACN’s draft recommendations: sugars
• A definition for ‘free sugars’ should be adopted in the
UK.
• This definition comprises all monosaccharides and
disaccharides added to foods by the manufacturer, cook or
consumer, plus sugars naturally present in honey, syrups
and unsweetened fruit juices. This definition excludes
lactose when naturally present in milk and milk products.
SACN’s draft recommendations: sugars
• The DRV for free sugars should be set at a population
average of around 5% dietary energy for age groups
from 2 years upwards.
• This is based on the need to limit free sugars to no more
than 10% of total energy intake at an individual level.
• Consumption of sugars-sweetened beverages, by
children and adults, should be minimised.
• Relevant to energy intake, weight gain (children), dental
caries, T2DM Risk (adults)
Sugars consumption in RCTs vs.
daily energy intake
Sugars and Health risks
• An association between greater sugars-sweetened beverage consumption
and higher incidence of type 2 diabetes mellitus (RR=1.07, 95% CI 1.05,
1.08 for each 100ml/day increase
• Sugars-sweetened beverages and BMI
– Effect
– Limited evidence
– The direction of the effect demonstrates that greater consumption of sugarssweetened beverages is detrimental to health
• Sugars containing foods and drinks – substantial evidence of increased risk
of dental caries
SACN’s draft recommendations: dietary fibre
• The definition of dietary fibre should be broadened
• The DRV for dietary fibre for an adult population should
be 30g/day (using the new definition)
• The average intakes for children aged 2-5, 5-11, 11-16,
16-18 years should be 15g, 20g, 25g, 30g respectively
• Dietary fibre intake should be obtained from a variety of
foods e.g. whole grains, pulses, potatoes, fruit and
vegetables where it is a naturally integrated component.
Risk of CVD with increasing levels of total fibre
intake (similar plots for other disease outcomes)
Next steps
• Draft report out for public consultation on scientific
aspects of the report from 26 June – 1 September
• Following consultation, the carbohydrate working group
and then the SACN main committee will consider how to
respond to scientific comments and may amend the draft
report
• The report will be signed off by the SACN Chair and the
main committee; the aim is to publish around end 2014 /
beginning 2015.
• PHE will consider whether dietary advice about
carbohydrates needs to be amended.
• Implications for Responsibility Deal?
Draft Carbohydrates and Health report
Scientific consultation: 26 June to 1 September 2014