Bread: As a source of nutrients

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Bread
as a source of nutrients
© FAB and AHDB 2013
Learning Objectives
• To learn about the nutrients provided by
bread, including their function in the
body.
• To review the differences in the nutrient
content of types of bread.
• To understand why nutrients are added to
white and brown flour.
• To examine the contribution of bread to
nutrient intakes in the UK.
© FAB and AHDB 2013
Nutrients in bread
Bread provides several important
nutrients and makes an important
contribution to the UK diet.
The main macronutrient provided by
bread is carbohydrate, but it also provides
some protein and a little fat.
Bread also provides fibre.
© FAB and AHDB 2013
Nutrients in bread
Bread provides vitamins and minerals, and
other substances with a beneficial effect on
health (called ‘phytochemicals’).
The nutrient content of bread will mainly
depend on the type of grain and flour used.
© FAB and AHDB 2013
What do you think? Is
bread a…




low
medium
high
very high
…energy food?
ANSWER: One gram of bread provides around
9.2kJ (2.2 kcal), which makes bread a ‘medium
energy’ food.
© FAB and AHDB 2013
Energy content of bread
Energy density is the amount of energy
(kJ/kcal) provided per gram of food.
1g bread
=
9.2kJ
(2.2 kcal)
© FAB and AHDB 2013
Energy density
Kcal/g
kJ/g
Very low
0 – 0.6
0 – 2.5
Low
0.6 – 1.5
2.5 – 6.3
Medium
1.5 – 4.0
6.3 – 16.7
High
4.0 – 9.0
16.7 – 37.7
Energy content of bread
One medium slice of bread (40g)
provides around 353-402 kJ (8794 kcal).
This is around 3-3.5% of daily
energy requirements for 15 year
old boys, and 3.5-4% for 15 year
old girls.
Adding spreads that are high in fat
will significantly increase the
energy content – it is better to add
toppings with a low energy and fat
content.
Estimated Average
Requirements for energy*
Age
Male
Female
13 years
10.1 MJ
(2400 kcal)
9.3 MJ
(2200 kcal)
15 years
11.8 MJ
(2800 kcal)
10.0 MJ
(2400 kcal)
17 years
12.9 MJ
(3100 kcal)
10.3 MJ
(2450 kcal)
Adults (>18
years)
10.9 MJ
(2600 kcal)
8.7 MJ
(2050 kcal)
*For people who are moderately active; people
who are very active are likely to need more, people
who are inactive are likely to need less
© FAB and AHDB 2013
Source: SACN, 2011
Macronutrients and fibre
Carbohydrate
Carbohydrate is the main
macronutrient in bread and is
present mainly in the form of
starch.
 Bread contains around 4247g of carbohydrate per
100g.
 Carbohydrates contribute
around 77-84% of the total
energy content of bread.
100
90
80
70
60
50
40
30
20
10
0
77-84%
42-47g
Grams
Contribution to
carbohydrate per energy content of
100g bread
bread
© FAB and AHDB 2013
Macronutrients and fibre
Carbohydrate
The main function of carbohydrate is to
provide energy. At least 50% of our energy
intake should come from carbohydrate.
© FAB and AHDB 2013
Macronutrients and fibre
Protein
Bread also provides some protein.
 Bread contains around 8-10g
of protein per 100g.
 Protein contributes around
15-16 % of the total energy
content of bread.
Protein is needed for growth and
repair of body tissues.
20
18
16
14
12
10
8
6
4
2
0
15-16%
8-10 g
Grams protein Contribution of
per 100g bread protein to energy
content of bread
© FAB and AHDB 2013
Macronutrients and fibre
Fibre
Fibre is important for gut health. Not
eating enough fibre can lead to digestive
problems, such as constipation.
Fibre also bulks up meals without
providing much energy and can make us
feel more satiated. This means that fibre
can help with appetite control, weight
maintenance and weight loss.
© FAB and AHDB 2013
Macronutrients and fibre
Fibre
Most of the fibre in bread is
provided by the bran, the outer
layer of the grain.
Wholemeal, wheat germ, brown
and granary bread provide more
fibre than white bread, but all
types of bread contain some
fibre.
© FAB and AHDB 2013
Fibre content in g per slice
(40g)
3
2.0g
2
1
0
1.4g
0.8g
1.3g
What proportion of the
recommended daily fibre intake
do 2 slices of wholemeal bread
provide?




5%
10%
15%
20%
ANSWER: Two slices of bread provide 20% of the
recommended daily intake.
© FAB and AHDB 2013
Macronutrients and fibre
Fibre
The recommended intake for fibre for adults is 18g
a day. Two slices of wholemeal bread provide
around 20% of the recommended fibre intake
(3.6g).
Most people in the UK do not consume enough
fibre, and so eating bread, particularly wholemeal
bread, can make a valuable contribution to the diet.
© FAB and AHDB 2013
What proportion of the
recommended intake of dietary
fibre do the following provide?
Breakfast: 2 slices of
wholemeal toast
=
g fibre
Lunch: 2 slices
malted grain bread
from a sandwich
=
g fibre
Dinner: 1 small
white bread roll
with dinner (40g)
=
g fibre
© FAB and AHDB 2013
Fibre content in g per
slice (40g)
Total fibre
from bread:
g
3
2.0g
2
1.4g
=
% of
recommended
18g/day
1
0
0.8g
1.3g
What proportion of the recommended
intake of dietary fibre do the following
provide?
Breakfast: 2 slices of
wholemeal toast
=
4.0 g fibre
Lunch: 2 slices
malted grain bread
from a sandwich
=
2.6 g fibre
Dinner: 1 small
white bread roll
with dinner (40g)
=
0.8 g fibre
© FAB and AHDB 2013
Total fibre
from bread:
7.4 g
=
41 % of
recommended
18g/day
Fibre content in g per
slice (40g)
3
2.0g
2
1.4g
1
0
0.8g
1.3g
Micronutrients - Vitamins
Folate:
 Folate is needed for the formation of
healthy red blood cells.
 It is also needed for the development of
the nervous system, specifically to reduce
the risk of neural tube defects in unborn
babies.
Thiamin (vitamin B1) and Niacin
(vitamin B3):
 Are needed for the release of energy from
food and for the normal function of the
nervous system, muscles and skin.
© FAB and AHDB 2013
Micronutrients - Minerals
Calcium:
 Calcium is needed for the formation and
maintenance of strong bones and teeth,
and the normal functioning of nerves and
muscles.
 In the UK more than 18% of girls and 7% of
boys aged 11-18 years have low calcium
intakes.
Iron:
 Iron is needed for transport of oxygen in
red blood cells and for the functioning of
enzyme systems.
 Low iron intakes are particularly common
in young women.
© FAB and AHDB 2013
Micronutrients - Minerals
Magnesium:
 Magnesium helps release and utilise
energy from foods, and is involved in
bone metabolism.
Zinc:
 Zinc is required for various enzymes.
 Low zinc intakes have been observed in
adolescents.
© FAB and AHDB 2013
Micronutrients - Minerals
Selenium:
 Protects against oxidative damage,
and is important for immune system
and reproductive function.
 In the UK a substantial proportion of
11-18 year-olds have low selenium
intakes.
© FAB and AHDB 2013
Micronutrients - Minerals
Sodium (Salt)
Bread also contains sodium (salt), at
varying levels. This is because salt is
added during the bread making process
as it plays an important functional role.
Over the last decade, much work has
been done to lower the salt content of
bread. The content has been reduced by
23% since 2004, and is likely to have
fallen by 40% since reformulation first
began in the 1980s/1990s.
Changes in salt levels
of bread since
2004
1980s/
90s
-23%
-40%
© FAB and AHDB 2013
O’Connor, 2012.
Phytochemicals –
for extra benefits
Bread, as well as other plant foods,
provides phytochemicals.
These are plant components that are not
nutrients, but are still beneficial for
health.
Exactly how these plant components
affect our health, and to what extent, is
currently being researched.
© FAB and AHDB 2013
Phytochemicals –
for extra benefits
The highest amounts of phytochemicals
are found in the outer layers of the
grain.
This means that wholemeal bread will
contain more phytochemicals than white
bread.
© FAB and AHDB 2013
Nutrients added to white
and brown flour
Some of the micronutrients in bread are
located in the bran (the outer layer). This
means that when removing the bran during
milling, for example when producing white
and brown flour, some of the micronutrients
are lost.
During and after World War II, to counteract
nutrient deficiencies within the population
caused by food shortages, it became
mandatory in the UK to add some of these
nutrients back to flour.
© FAB and AHDB 2013
Nutrients added to white
and brown flour
Bread was eaten by most people and was
therefore an effective vehicle for nutrient
fortification.
Iron, thiamin and niacin were added to
restore levels that are naturally present in
the whole grain. Calcium was added for
fortification purposes as dairy products
were limited due to rationing during that
time.
© FAB and AHDB 2013
Nutrients added to white
and brown flour
Today, in the UK, some people have
suboptimal intakes of these nutrients, and
therefore the addition of these nutrients to
flour remains mandatory.
A group of experts recently concluded that
if the nutrients were no longer added, this
would have a negative impact on UK
vitamin and mineral intake levels, in
particular amongst those in the most
vulnerable population groups (e.g. the
elderly).
SACN, 2012
© FAB and AHDB 2013
Nutrient content of
different bread types
The next slide shows a table of the
nutrient contents of different types of
bread.
What differences and similarities do
you notice?
© FAB and AHDB 2013
Nutrient content of different
bread types (per 100g)
White
bread
Brown
bread
Wholemeal
bread
Multi grain
bread
Energy (kJ)
931
882
922
1005
Energy (kcal)
219
207
217
237
Fibre (g)
1.9
3.5
5.0
3.3
Calcium (mg)
177
186
106
209
Iron (mg)
1.6
2.2
2.4
1.9
Magnesium (mg)
23
45
66
39
Zinc (mg)
0.8
1.3
1.6
1.1
Selenium (µg)
6
4
7
6
Thiamin (mg)
0.24
0.22
0.25
0.24
Niacin (mg)
1.6
2.8
3.8
2.7
Folate (µg)
25
45
40
88
© FAB and AHDB 2013
Myth or Fact?
“Modern bread is less
nutritious than traditionally
produced bread.”
© FAB and AHDB 2013
Modern vs. traditional bread
There is a misconception that modern
bread is less nutritious than more
traditional bread. But this is not true.
There is no difference in nutrient
content between bread made the
modern or traditional way.
The nutrient content of bread mainly
depends on the type of flour used and
the addition of nutrients during
milling.
© FAB and AHDB 2013
Contribution of bread to UK
nutrient intakes
Bread makes an important contribution to
the nutrient content of the UK diet.
The next slide shows the proportion of
specific nutrients that people in the UK get
from bread.
These are average population values, and
the actual contribution of bread will, of
course, depend on the amount each
individual eats and the other food choices
made.
© FAB and AHDB 2013
Contribution of bread to UK
nutrient intakes
+Macronutrients
Carbohydrate
Protein
16-20%
Dietary fibre
20%
9-11%
*Vitamins
*Minerals
Thiamin
14%
Calcium
19%
Folate
11%
Iron
15%
Niacin
11%
Magnesium
13%
Zinc
11%
Potassium
5%
Selenium
5%
* NDNS (2000/2001)
+ NDNS (2010/2011)
© FAB and AHDB 2013
Contribution of bread
to UK nutrient intakes
On average, 2 ½ slices of bread are
consumed each day.
In the 1940s people ate on average 7 slices
of bread per day, so the contribution of
bread to nutrient intakes would have been
higher.
© FAB and AHDB 2013
How lower bread intake
can impact on nutrient intake
Changing anything in our diet will alter
nutrient intake, although this will always
depend on what a certain food is replaced
with (if at all).
Bread is a starchy food and therefore the
basis for meals, for example as toast for
breakfast, or as a sandwich for lunch.
© FAB and AHDB 2013
How lower bread intake
can impact on nutrient intake
If bread is replaced by another starchy food, for
example breakfast cereal in the morning or a jacket
potato for lunch, then the nutrient intakes will be less
affected than if bread is simply avoided and not
replaced by other starchy foods.
If bread is avoided, this can have a substantial impact
on nutrient intakes, including dietary fibre.
© FAB and AHDB 2013
How lower bread intake
can impact on nutrient intake
Intakes of some of the micronutrients
present in bread are already low in some
groups within the UK (e.g. iron, calcium,
magnesium, selenium and folate).
Avoiding bread and starchy foods, or any
other major food group, increases the risk
of inadequate nutrient intakes, which can
affect health.
© FAB and AHDB 2013
Summary
 Bread provides a number of nutrients that are
important for health.
 Bread is an important contributor to fibre and
nutrients, such as calcium and iron, in the UK diet.
 Certain nutrients are added to white and brown
flour during milling to restore levels lost when
removing the bran or for fortification purposes, to
increase the population’s intake of specific
nutrients
 Wholemeal bread is higher in fibre than white or
brown bread so a good choice for many of us.
© FAB and AHDB 2013
Summary
 The nutrient content of bread mainly depends on the
type of flour used (white, wholemeal or brown), and
not the method used for bread making.
 Bread also provides phytochemicals, which are
beneficial for health.
 Avoiding bread along with other starchy foods in the
diet can increase the risk of insufficient nutrient and
fibre intakes.
© FAB and AHDB 2013
Quiz
Time to test your knowledge!
Home
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END
Question 1
What proportion of our daily energy intake
should be provided by carbohydrate?
A. 30%
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B. 40%
C. 50% or more
Correct!
Next
question
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Incorrect
Try again
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Next
question
Question 2
What is the recommended daily fibre intake
for adults?
A. 18g
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B. 20g
C. 22g
Correct!
Next
question
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Incorrect
Try again
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Next
question
Question 3
Which of these nutrients must be restored
during the bread making process in UK law?
A. Thiamin
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B. Sodium
C. Potassium
Correct!
Next
question
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Incorrect
Try again
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Next
question
Question 4
Which type of bread provides the most
fibre?
A. Granary
bread
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B. Brown
bread
C. Wholemeal
bread
Correct!
Next
question
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Incorrect
Try again
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Next
question
Question 5
Which macronutrient is provided in the
largest amount by bread?
A. Protein
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B. Carbohydrate
C. Fat
Correct!
Next
question
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Incorrect
Try again
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Next
question
Question 6
A lack of fibre in the diet can lead to which
of the following?
A. Tiredness
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B. Anaemia
C. Digestive
problems
Correct!
Next
question
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Incorrect
Try again
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Next
question
Question 7
What is the energy density of bread?
A. Low
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B. Medium
C. High
Correct!
Next
question
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Incorrect
Try again
© FAB and AHDB 2013
Next
question
Question 8
How much of the daily fibre requirements
do two slices of wholemeal bread provide?
A. 5%
© FAB and AHDB 2013
B. 15%
C. 20%
Correct!
End of quiz
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Incorrect
Try again
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End of
quiz
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