Transcript Too Little & Too Much Food

Noadswood Science, 2012
Friday, July 17, 2015
BER & BMI

To understand the terms BER and BMI
Energy

Where do we get our energy from, and what do we use it
for?

Our energy is derived from food - whereas plants can
produce their own energy from sunlight, we must consume
food

This food is our raw material - needed to make new
substances for:  Energy (movement etc…)
 Growth and repair
 Health
Balanced

A balanced diet contains the different nutrients in the correct
amounts, keeping us healthy

Certain foods are not necessarily 'bad' for us, but eating too
much of them could be

Foods contain nutrients: these are substances which provide
raw materials for the body (we need nutrients, along with
fibre and water for a healthy diet)

There are seven different nutrients, and some foods are
particular rich in certain nutrients…
Essential

Nutrients are found within different foods, and they all play
important roles within the body
Nutrient
How the body uses it
Food sources it is contained in
Carbohydrate
To provide energy
Cereals; bread; pasta; potatoes (sugars
and starch)
Protein
For growth, making new cells and repair
of our bodies
Fish; meat; eggs; dairy products
Fat
To provide energy, as a store of energy &
for insulation
Butter; oil; nuts
Minerals
Needed in small amounts to maintain
health
Salt; milk (calcium); liver (iron)
Vitamins
Needed in small amounts to maintain
health
Dairy foods; fruit; vegetables
Fibre
To provide roughage to help keep food
passing through the gut
Vegetables; bran; wholemeal bread
Water
Needed by cells and for body fluids
Fruit juice; milk; water(!)
Food

Complete the food
worksheet…
Food
Right Amount Of Food – Too Little

If you don't eat enough food, you will become too thin and
may suffer from health problems…

These problems can include:  Irregular periods in women
 Reduced resistance to infection
 Deficiency diseases
Right Amount Of Food – Too Little

Deficiency diseases include rickets and kwashiorkor

Rickets affects proper growth of the skeleton and is caused
by insufficient vitamin D

Kwashiorkor causes a swollen abdomen and is a result of
insufficient protein

Problems such as these are more likely to affect people in
the developing world, where it can be more difficult to get
enough food
Right Amount Of Food – Too Much

In warm weather, or when you don't do much exercise, you
do not need to eat as much food as when it is cold or when
you have exerted yourself physically

If you eat too much food without taking enough exercise, you
will become overweight

Very fat people are described as obese
Right Amount Of Food – Too Much

Overweight people may suffer from health problems,
including:  Diabetes (type 2) - an illness in which the body is unable
to control the amount of sugar in the blood
 Arthritis - an illness in which the joints become worn,
inflamed and painful
 High blood pressure
 Heart disease
BMI

BMI (body mass index) is a scale to determine your ideal
weight

The calculation is your weight (kg) ÷ height2 (m)
BMI

BMI is not always right! Look at the two people below – why
might there BMI tell them they are unhealthy?!
Body builder - very high BMI (although this is
overwhelmingly muscle, not fat)
Elite marathon runner – very low BMI (very
healthy diet, just so many calories constantly
burnt running (~1000 per hour))
Body Fat

The average person has between 17 and 25% body fat

A large proportion of the population may be well over 30%

An oarsman at the peak of his game will probably be
between 8 and 12%
Body Fat

To calculate body fat use the callipers and pinch your skinfold at various points (take an average in mm)

Identify your weight (kg), height (m), age and gender

Body fat %...
Body Fat – Men (All Locations)
Skin-fold
(mm)
Age
16-29
30-39
40-49
50+
16
18
20
22
6.7
7.9
8.1
9.2
9.3
10.8
12.0
13.0
9.5
10.9
12.2
13.5
9.7
11.0
12.5
13.9
24
26
28
30
10.2
11.2
12.1
12.9
13.9
14.7
15.5
16.2
14.6
15.7
16.7
17.6
15.1
16.3
17.4
18.5
35
40
45
50
14.7
16.3
17.7
19.0
17.8
19.2
20.4
21.5
19.7
21.5
23.1
24.6
20.8
22.8
24.7
26.3
55
60
65
70
20.2
21.2
22.2
23.2
22.5
23.5
24.3
23.2
25.9
27.1
28.2
29.3
27.8
29.1
30.4
31.5
75
80
85
90
24.0
24.8
25.6
26.3
25.9
26.6
27.6
28.3
30.2
31.2
32.1
32.9
32.6
33.7
34.6
35.5
95
100
110
120
27.0
27.6
28.8
29.9
29.0
29.7
30.9
32.0
33.8
34.5
35.8
37.1
36.5
37.3
38.8
40.2
130
140
150
160
31.0
31.9
32.8
33.6
33.0
34.0
34.8
35.7
38.2
39.4
40.4
41.4
41.5
42.8
43.9
45.0
170
180
190
200
34.4
35.2
35.9
36.5
36.5
37.2
37.9
38.6
42.3
43.1
43.9
44.7
46.0
47.0
47.9
48.8
Body Fat – Women (All Locations)
Skin-fold
(mm)
Age
16-29
30-39
40-49
50+
14
16
18
20
9.4
11.2
12.7
14.1
12.7
14.3
15.7
17.0
15.6
17.2
18.5
19.8
17.0
18.6
20.1
21.4
22
24
26
28
15.4
16.5
17.6
18.6
18.1
19.2
20.1
21.1
20.9
22.0
22.9
23.8
22.6
23.7
24.8
25.7
30
35
40
45
19.5
21.6
23.4
25.0
21.9
23.8
25.5
27.0
24.6
27.2
28.1
29.6
26.6
28.6
30.3
31.9
50
55
60
65
26.5
27.8
29.1
30.2
28.3
29.5
30.6
31.6
30.9
32.1
33.2
34.2
33.2
34.6
35.7
36.7
70
75
80
85
31.2
32.2
33.1
34.0
32.6
33.5
34.3
35.2
35.1
36.7
36.8
38.4
37.7
38.6
39.5
40.4
90
95
100
110
34.8
35.6
36.3
37.7
36.0
36.7
38.4
38.7
39.1
39.9
40.6
41.8
41.1
41.9
42.6
43.9
120
130
140
150
39.0
40.2
41.3
42.3
39.9
41.1
42.1
43.1
43.0
44.1
45.1
46.0
45.1
46.2
47.3
48.2
160
170
180
190
43.2
44.6
45.0
45.8
44.0
45.1
45.6
46.4
46.9
47.8
48.5
49.3
49.1
50.0
50.8
51.6
Basic Energy Requirements

Basic Energy Requirements (BER) is based on how much
you weigh, and gives an indication of how much energy you
need per hour (though this will be dependent on your lifestyle
(e.g. your age / if you’re active / pregnant etc…))

For every kilogram of your weight you need 5.4kJ to keep
you alive
BER (kJ) = Weight (kg) x 5.4
E.g. 80kg man would have a BER of 432kJ per hour
BER of 10’368kJ per day (or 2476 calories)
* 1kJ = 0.24 calories
Food Diary

Daily energy requirements of an individual depend on their
mass (weight) and that this requirement also increases
during exercise

Diet diaries are used by athletes to recall their food intake (a
basic one is over a period of 24 hours, however the longer it
is taken the more accurate it becomes) – they can then
compare this to their exercise routine (and how many
calories each activity is using) and this will make their
specific BER more accurate…

Using the worksheet complete your own food diary (write the
type of food and portion size (and ideally the calorie intake))
over a 24 hour period, and note time the energy you used
depending upon the type of exercise you did in that time
Food Diary