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the recent introduction of free academic supports on campus for math, science,
and business (Math & Science Centre), as well as support for improving study
skills, time management, etc. (Academic Success Coaching).
•excellent academic supports available to students:
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Addition to lecture 2A-use a lactose-free dairy product (lactose
removed when lactose-free dairy product is
made) e.g. some lactose-free milk products
are currently available.
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chicory seed-food additive
-resistant carbohydrate
causing decreased pHdue to short chain fatty
acid production
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Questions about diet/exercise records
Project (or essay option)?
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Lecture 4a- 28 September 2015
CARBOHYDRATES IV
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Overview of lecture 4A
Carbohydrates
- sugars in health and disease
- complex carbohydrates in health
and disease
- where are carbohydrates found
- dietary recommendations
- what’s new and exciting
- next lecture-FIBRE
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Carbohydrates in health-sugars
Nutrient deficiencies- empty kcal
Dental caries – sugar will cause caries
and therefore good oral hygiene
important
Obesity – when consumed in excess
sugars cause obesity due to conversion
of sugar to fat- see next slide first point
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Carbohydrates in health-sugars
continued
Heart disease –lots of refined sugar leads
to alterations in blood lipids in
carbohydrate sensitive individuals-due to
increased insulin response that builds fat
Misbehaviour in children and
criminal behaviour in adults – mythnothing to support scientifically these
suggestions
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Carbohydrates in health continued
But sugars in foods are not all bad-many
functional properties of carbohydrates
in foods- e.g. taste, physical and chemical
properties and antimicrobial purposes
Weight control-foods rich in complex
carbohydrate are usually low in fat and added
sugars and provide
-less kcal per bite
-also satiety and delayed hunger due to
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glycemic index issue
Carbohydrates in health continued
Complex carbohydrate foods also help with
Heart disease
-high complex carbohydrate and low
cholesterol diets reduce risk of heart
disease
-such high complex carbohydrate and low
cholesterol diets are low in animal fat and
cholesterol and high in soluble fibres and
vegetable proteins
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Carbohydrates in health-starches
continued
Cancer
-lower risk with high complex carbohydrate
diet that has loads of green and yellow
vegetables and citrus fruit
-nature of preventative effect is not clear
Type 2 diabetes-lower risk with high
complex carbohydrate diets-most likely due
to such diets being low in fat- also likely
due to lower glycemic index issue
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Carbohydrates in foods
Glucose- e.g. fruits, veggies, honey
Fructose- e.g. fruit and honey
Galactose-rarely in food -mostly in form of lactose
Sucrose-minimal amounts in some fruits and veggies- e.g.
beets
Maltose -none naturally in food
Lactose - milk and other dairy products
Oligosaccharides – e.g. inulin – chicory, Jerusalem
artichoke
Starch- e.g. potatoes
Glycogen- e.g.- meats little rapid conversion to lactic13acid
at slaughter
DIETARY Recommendations-DRI
Carbohydrates be 45-65 % of energy
or 900-1300 kcal of carbohydrate or 225-325 grams
of carbohydrate per total energy intake of 2000
kcal/day
-carbohydrates from a variety of sources with
increases in complex carbohydrates are
recommended
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DIETARY Recommendations
DRI- Added sugars (simple sugars)-no more than 25
% of calories- but that is 500 kcal or 125 grams (31
teaspoons) of sugars- this is too much
WHO and FAO – recommend less than 10 % of
calories as added sugars-200 kcal or 50 grams-this is
better idea than the DRI recommendation-in March
2014, WHO proposed that a reduction to below 5%
of total energy intake per day would have additional
benefits. Five per cent of total energy intake is
equivalent to around 25 grams (around 6 teaspoons)
of sugar per day for an adult of normal Body Mass
Index (BMI).
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Reducing added sugar
https://www.uoguelph.ca/hpc/sites/uoguelph.ca
.hpc/files/files/RP_Cranberry%20Orange%20S
pritzer.pdf
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What is new in carbohydrates?
Glycaemic index review by Health Canada
Aziz, A, Dumais, L., Barber J. Health Canada's
evaluation of the use of glycemic index claims on food
labels. American J. Clin Nutr. 2013 Aug;98(2):269-74.
doi: 10.3945/ajcn.113.061770. Epub 2013 Jun 12.
•Nutrition Research Division and the Nutrition
Regulations and Standards Division, Bureau of Nutritional
Sciences, Food Directorate, Health Products and Food
Branch, Health Canada, Ottawa, Canada. [email protected]
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What is new in carbohydrates?
Aziz et al. American Journal of Clinical Nutrition 98:26974(2013).
“Health Canada's assessment identified 3 areas of concern with respect to
GI labelling:
1)the GI measure has poor accuracy and precision for labelling purposes;
2) as a ratio, the GI does not vary in response to the amount of food
consumed and the partial replacement of available carbohydrates with
unavailable carbohydrates, whereas the glycemic response does;
3) an unintended focus on the GI for food selection could lead to food
choices that are inconsistent with national dietary guidelines. Hence,
Health Canada's current opinion is that the inclusion of the GI value on
the label of eligible food products would be misleading and would not
add value to nutrition labeling and dietary guidelines in assisting
consumers to make healthier food choices. “
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What is new in carbohydrates?
Artificial sweeteners – linked to weight gain and to increased risk of
type 2 diabetes- a number of papers
Saccharin changes gut microbiota in mice which in turn contributes to
glucose intolerance and hence the risk of type 2 diabetes
Nature 514, 181–186 (09 October 2014)
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