Adolescent Nutrition

almondpitterpatterIA et Robotique

23 févr. 2014 (il y a 3 années et 4 mois)

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A
DOLESCENT

N
UTRITION

Dr.Fatemeh Famouri

Pediatric Gastroenterologist

ADOLESCENCE


It is the time between the onset of puberty and adulthood (
11
-

17
years old)



Boys grow about
8
inches, gain about
45
pounds and increase their


lean body mass.


Girls grow about
6
inches, gain about
35
pounds and increase their


body fat.



Growth through adolescence is hormone driven. Growth spurts for girls


begin between ages
10.5
and
11
years with a peak in the rate of growth at
around age
12
.



Considerable gain in muscle and bone mass
















D
EFINITION


• Early adolescence:
10
-
15
years;

• Mid adolescence:
15
-
17
;

• Late adolescence :
17
-
21
, but variable.


differences between
genders becomes apparent


females: higher fat
percentage


males: more lean body
mass




Adolescence is an uncomfortable time for the teen who is concerned with body
image or body changes or athletic activities.


Low nutrient snacks are a large part of the diet and adequate amounts of fruits and


vegetables are missing.


Factors that determine food selection and consumption include the desire to be

healthy, fitness goals, amount of discretionary income, social practices and peers.




improved nutrition in adolescence,particularly in girls,
is the reduced risk of osteoporosis in older age.




stunting becomes a permanent consequence of past
malnutrition rather than being a sign of present
malnutrition.




If there is indeed catch
-
up growth in height,
adolescence can provide a final chance for intervention
to promote additional growth,with potential benefit in
terms of physical work capacity and for girls, of
diminished obstetric risk


.


Linear growth may be limited by multiple
simultaneous nutrient deficiencies in many
populations,


which could explain that interventions with
specific individual nutrients (eg
, vitamin A, iron,
zinc
)








increased pre
-
pregnancy weight and body stores of
nutrients, thus contributing to improved future pregnancy
and lactation outcome,




improved iron status with reduced risk of
anaemia

in
pregnancy, low birth weight, maternal morbidity and
mortality, and with enhanced work productivity and
perhaps linear growth;




improved
folate

status, with reduced risk of neural tube
defects in the newborn and
megaloblastic

anaemia

in
pregnancy.



Small girls are likely to become small women who are more
likely to have small babies, particularly if at a young age



The overall nutritional status is better assessed
with
anthropometry
, in adolescence as well as at
other stages of the life cycle. Anthropometry is
the single most inexpensive, non
-
invasive and
universally applicable method of assessing body
composition, size and proportions


Iodine deficiency disorders


Iodine deficiency disorders were widely prevalent
in most populations



Neuromotor and cognitive impairments of
variable degrees


Iodine deficiency is recognized as the most
common cause of preventable mental retardation
in the world.

Z
INC


Evidence from supplementation trials suggests that
marginal zinc nutriture may also limit skeletal growth




zinc supplementation increased accretion of fat
-
free
mass and enhanced linear growth in those that were
stunted at baseline

Figure
18.4


C
ALCIUM


½ of peak bone mass
accumulates in adolescence


AI for calcium =
1
,
300
mg
for ages
9

18
years


Inadequate calcium intake
can lead to low peak bone
mass and is a risk factor for
osteoporosis

T
EENAGERS

AND

CALCIUM


Teenagers have high calcium requirements.



Around
50
% of the adult skeleton is formed during
the teenage years (RNI
-

boys
1000
mg/day, girls
800
mg/day).



Low calcium intakes (< LRNI) found in
24
% of
11
-
14
year
-
old girls and
19
% of
15
-
18
year
-
old girls.



A lack of calcium may have consequences for future
bone health e.g. increased risk of osteoporosis.


I
RON


Additional iron supports muscle growth and
increased blood volume


Adolescent females need iron to support
menstruation


RDA for iron


Females aged
14

18
years =
15
milligrams


Males aged
14

18
years =
11
milligrams


Iron deficiency is common in adolescence,
especially among individuals who limit intake of
enriched
grains, lean meats, and legumes

I
RON

ABSORPTION


Good sources: meat (especially lean red meat), liver
and offal, green leafy vegetables, pulses (beans,
lentils), dried fruit, nuts and seeds, bread and
fortified breakfast cereals.



Iron from meat sources (heme iron) is readily
absorbed by the body.



Vitamin C helps the body to absorb iron from other
sources (non
-
heme iron).

A
HEALTHY

DIET

IS

IMPORTANT

FOR

TEENAGERS

Eating a healthy, balanced diet can:



promote wellbeing by improving mood, energy and self
-
esteem to
help reduce anxiety and stress;



best concentration and performance;



reduce the risk of ill
-
health now and in the future, e.g. obesity,
heart disease, cancer, and type
2
diabetes;



increase productivity/attainment and reduce days off sick.


N
UTRIENT

NEEDS

OF

ADOLESCENTS


Growth not age should be ultimate indicator of nutrient needs.


Energy needs are greater during adolescence than at any other time of life with
exception of pregnancy & lactation.


Energy & Proteins RDAs

Males

Age (yrs) Kcal/kg Kcal/day Proteins g/kg Proteins
gm/day

11
-
14 55 2500 1.0 45

15
-
18 45 3000 0.9 59

Females

Age (yrs) Kcal/kg Kcal/day Proteins g/kg Proteins
gm/day

11
-
14 47 2200 1.0 46

15
-
18 40 2200 0.9 44


Vitamins & Minerals


Higher vitamins and minerals needs.


Three nutrients of importance i.e. vitamin A, iron and calcium.


AI for calcium
1300
mg/day, for iron is
11
mg/day (boys) and
15
mg/day (girls).


Improving fruit & vegetable intake will help in obtaining adequate vitamin A.




D
IETARY

RECOMMENDATIONS

Teenagers should consume a variety of foods from each of
the four main food groups:

Fruit and vegetables (
33
%)

Bread, rice, potatoes,
pasta and other starchy
foods (
33
%)

Milk and dairy foods (
15
%)

Meat, fish, eggs, beans
and other non
-
dairy
sources of protein (
12
%)

F
OOD

G
UIDE

P
YRAMID



serving sizes can help you control the amount of
calories, fat, saturated fat, cholesterol, sugar or
sodium in your diet.



Grains, Bread, Cereal and Pasta form the Base


Fruits and Vegetables


Lean Meat and Fish, Beans, Eggs


Dairy Products


Fats and Sweets








M
ACRONUTRIENTS

Macronutrient

Recommended
intake

(% food energy)

Boys average
intake

(% food energy)

Girls average
intake

(% food energy)

Fat

35%

35.4%

35.9%

of which saturates

11%

14.2%

14.3%

Carbohydrate

50%

51.6%

51.1%

of which added
sugars (NMES)

11%

16.7%

16.4%

-

average intakes

(Scottish NDNS and Survey of Sugar Intake data)

W
HAT

ABOUT

DIETARY

FIBER
?



average dietary fibre intakes to be low in teenagers:


-

Boys (
11
-
14
years)
11.6
g/day


(
15
-
18
years)
13.3
g/day


-

Girls (
11

14
years)
10.2
g/day


(
15
-
18
years)
10.6
g/day



Reference values:


-

15
g/day (
11
-
14
years)


-

18
g/day (
15
years or above)

W
HAT

ABOUT

SALT
?


NDNS survey results
-

average salt intakes above
recommendations in teenagers:


-

Boys (
11
-
14
years)
6.75
g/day




(
15
-
18
years)
8.25
g/day


-

Girls (
11
-
18
years)
5.75
g/day


(excluding salt added in cooking or at the table


Recommended maximum daily salt intake:


-

11
years and over: up to
6
g/day.

T
EENAGERS

AND

ENERGY

BALANCE



Levels of overweight and obesity are increasing:
35
% of
teenagers (
12
-
15
years) are classified as overweight or
obese (Scottish Health Survey
2009
).



Teenagers, especially girls, often try to control their
weight by adopting very low energy diets or smoking.



Restricted diets may lead to nutrient deficiencies and
other health consequences.



Teenagers of unhealthy weight may need guidance on
lifestyle changes to help them achieve a healthy weight.

T
EENAGERS



PHYSICAL

ACTIVITY


Physical activity through life is important for
maintaining energy balance and overall health.


At least
60
mins of moderate
-
intensity physical activity
each day is recommended.




Include activities that improve bone health, muscle
strength and flexibility at least twice per week.



68
% of boys and
41
% of girls (
13
-
15
year
-
olds) achieve
the recommended
60
mins per day

D
IET

AND

COGNITIVE

ABILITY


Food eaten at school can make up a substantial
proportion of the diet and have a significant effect on
functions such as learning, memory, information
processing and mood.



Cognition represents a complex multidimensional set
of abilities and cognitive performance is affected by
many influencing factors.



Nutritional effects are difficult to measure.

Stevenson J (
2006
) Dietary influences on cognitive
development and behaviour in children
Proct Nutr Soc
65
(
4
):
361
-
5
.

Bellisle F (
2004
) Effects of diet on behaviour and
cognition in children
Br J Nutr
92
Suppl
2
: S
227
-
32
.

G
LYCEMIA

The brain appears to be sensitive to short
-
term
fluctuations of glucose supply and therefore it
might be beneficial to maintain glycemia at
adequate levels to optimise cognition.

E
ATING

BREAKFAST


Starting each day with breakfast will supply
energy to the brain & body.



Eating breakfast leads to improved energy and
concentration levels throughout the morning.



Breakfast consumption may improve cognitive
function related to performance in school.


Improvement of memory



Other benefits of breakfast include better
nutrient intakes and weight control.


Even mild dehydration (
1
-
2
%) can lead to headaches,
irritability and loss of concentration. This level is not
enough to cause feelings of thirst.



The recommendation is to drink
6
-
8
glasses/day (
1.2
litres) to prevent dehydration. People need to drink
more when the weather is hot or when they have
been active.



All drinks count in terms of fluid intake but those
without sugar are best between meals.

F
LUIDS

AND

HYDRATION

D
IET

AND

IQ


Brain health depends on optimal intakes of nutrients
from the diet.



Much speculation about the importance of long chain
omega
-
3
fatty acids to behavioural and cognitive
development, including IQ.



Supplementation studies show the best outcome
observed in children with learning disabilities.



Current recommendation is one portion of oily fish
(
140
g) per week.

D
IET

AND

MOOD
/
BEHAVIOUR


There are a number of foods that have a
pharmacological effect in the body which affects
mood:



* caffeine;


* vaso
-
active amines, such as histamine;


* tryptophan and serotonin.



There is evidence to suggest that poor vitamin and
mineral status may be associated with poor
educational attainment and antisocial behaviour
.

F
OOD

ADDITIVES

AND

HYPERACTIVITY


The Southampton study suggested that consumption
of mixes of certain artificial food
colours

and the
preservative sodium benzoate could be linked to
increased hyperactivity in some children. The
colours

are:



sunset yellow FCF (E
110
)



quinoline

yellow (E
104
)



carmoisine

(E
122
)



allura

red (E
129
)



tartrazine

(E
102
)



ponceau

4
R (E
124
)



An EU
-
wide mandatory warning must be put on any
food and drink (except drinks with more than
1.2
%
alcohol) that contains any of the six
colours
.

Bateman B
et al.
2007

E
ATING

H
ABITS


irregular eating habits


snacks generally provide ¼ of daily energy
intake


more fast food: less fruits, vegetables, milk


food choices are often dictated by peers



W
HAT

DO

BOYS

AND

GIRLS

WANT
?


boysys usually want to
gain muscle and get
taller


Girls usually want to
control their weight

F
OR

GIRLS

SOME

ADDITION

OF


FAT

IS

NATURAL


Need at least
17
% body
fat for normal periods


Diet is a four letter
word


Improve eating habits
and activity


but don’t
starve or over exercise

B
OYS

MATURE

LATER


Growth spurt up to
2
years later than girls


Full muscle mass
doesn’t develop until
one year after full
height achieved


Excess calories and
protein won’t speed
things up

M
AKE

EVERY

DRINK

COUNT


Cut the soft drinks



Drink
3
-
4
cups of milk


Drink at least
4
more
cups



of water or juice (watch
the juice


it has
calories)

D
URING

A

SPORTS

EVENT


Drink at least
2
cups of
water before event


Continue to drink
4
ounces every half hour


Cool, not cold, water is
best


Replace two cups of
fluid for every pound
lost

E
AT

AT

LEAST

5
SERVINGS

OF

FRUITS

AND

VEGETABLES


Lots of vitamins and
minerals with few
calories


More fiber so you feel
full


Portion size


palm of
girl’s hand

E
AT

MORE

WHOLE

GRAIN

BREADS

AND

CEREALS


Won’t cause weight gain
if don’t eat too much


Depending on body size,
will need
6
-
11
servings


Portion size


the palm
of a girl’s hand

G
ET

ENOUGH

PROTEIN

BUT

NOT

TOO

MUCH


Get protein from lean
meat, fish and poultry


Portion size


palm of
girl’s hand


Protein also comes from
dairy foods, dried beans
and peas, peanut butter,
nuts, seeds, soy foods


Limit low nutrient foods
with lots of fat, sugar
and sodium


Make fast food a special
occasion


choose grilled or broiled
meat, fish or poultry


choose side salads, baked
potatoes


choose milk, water or
juice

D
ISORDERED

E
ATING


Disordered eating patterns are more prevalent in
adolescent females than males


May be linked with poor body image or low self
-
esteem


Teens often adopt unhealthy habits such as


Skipping meals


Using food substitutes


Taking diet pills or nutritional supplements


Purging through vomiting, laxatives, or diuretics


Eating family meals promotes healthy eating
patterns




A
NOREXIA

N
ERVOSA



Refusal to maintain body weight over a minimal
normal weight.



Intense fear of gaining weight or becoming fat,
even though underweight.



Denial of low body weight.



In females, absence of at least
3
consecutive
menstrual cycles.

.

A
NOREXIA

N
ERVOSA
:

C
LINICAL

& L
ABORATORY

F
INDINGS


LANUGO and EDEMA of the skin, bradycardia
and hypotension, constipation, normochromic
anemia and leukopenia, hyponatremia,
hypoglycemia, low hormonal levels (estrogen or
testosterone, LSH, FSH)
but
normal
TSH and
increased
cortisol



SKELETAL CHANGE: OSTEOPENIA

A
NOREXIA

N
ERVOSA

S
IGNS

OF

M
ALNUTRITION

:


Easy pinching in the posterior region of the arms, due to
to loss of fat



Hollowing temporal muscles



Wasting of the tigh muscles



Easily plucked hairs


MEMO: the laboratory signs of malnutrition are
HYPOALBUMINEMIA and
HYPOPREALBUMINEMIA


T
REATMENT

FOR

A
NOREXIA

N
ERVOSA


Close supervision


Individual and family counseling


Self
-
acceptance


Time and patience


Nutrition therapy

B
ULIMIA

N
ERVOSA



Characterized episodes of binge eating alternating with
purging



Female to male ratio

10
:
1



Some genetic factors may be involved, but and above all
cultural attitudes

toward standards of physical
attractiveness



3
modalities are the most frequent:


Self induced vomiting via “fingers” or ipecac


Abuse laxatives (e.g.
bisacodyl
, cascara or
senna
)


Misuse diuretics



In addition to diuretics also diet pills (containing ephedrine)

B
ULIMIA

N
ERVOSA
: C
OMPLICATIONS


Oral: loss of enamel of the anterior teeth and dental
caries



GI tract: frequent vomiting can induce GE
-
reflux
(occasionally tears in the esophagus). The abuse of
laxatives can lead to constipation due to damage of the
myo
-
enteric plexus



Abnormalities of the electrolytes:


Metabolic alkalosis due to frequent vomiting


HYPOKALEMIA present in
5
% of the patients

B
ULIMIA

N
ERVOSA
: T
REATMENT


Replenish potassium losses



Eventually I.V. fluids and lytes



Monitor lytes frequently


and, of course



Refer for psychiatric or psychologic counseling

T
REATMENT

FOR

B
ULIMIA


Eating only at mealtime


Portion control


Close supervision after eating


Psychological counseling

O
BESITY
:

H
EALTH

C
ONSEQUENCES


Cardiovascular disease risk


Type
2
diabetes (epidemic)


Hypertension


Orthopedic


Sleep apnea


Gall bladder disease/steatohepatitis


Psychosocial problems

B
ODY

M
ASS

I
NDEX


Weight in kg divided by height in m
2



NORMAL BMI :
18
to
24
years of age

BMI <
18
:
suspect malnutrition

BMI
24
to
30
:
overweight

BMI
30
to
40
:
obesity

BMI above
40
=
morbid obesity

O
BESITY

T
REATMENTS


Caloric restrictions
: restrict fats to less than
30
% of the
total caloric intake



Modification of lifestyle and exercise
:


A walk of
1
mile (
1.5
m) burns
100
Kcal


Walk
2
-

3
-

or even
4
miles,
4
or
5
x weekly, and add some
resistance exercise
2
or
3
times weekly (all under some
supervision).


The dietary variations
: the high protein low
carbohydrate (only
20
grams of CHO/day)

F
INAL

C
OMMENTS

The recipe for effective weight loss is a combination of:


Motivation


Physical activity


Caloric restriction


And all this with a lifelong adherence

BUT

MEMO:
Prevention

of weight gain is the first step EVEN IN
CHILDREN