ADOLESCENTNUTRITION

Dr.Fatemeh FamouriPediatric 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 theirlean body mass.

� Girls grow about 6 inches, gain about 35 pounds and increase theirbody fat.

� Growth through adolescence is hormone driven. Growth spurts for girlsg p gbegin between ages 10.5 and 11 years with a peak in the rate of growth ataround age 12.

� Considerable gain in muscle and bone mass

DEFINITION

• Early adolescence: 10 -15 years;• Mid adolescence: 15-17;• Late adolescence : 17-21, but variable.

� differences betweengenders becomes apparent� females: higher fat

percentage� males: more lean body

mass

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

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

Factors that determine food selection and consumption include the desire to behealthy, 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 pastmalnutrition rather than being a sign of presentmalnutritionmalnutrition.

• If there is indeed catch-up growth in height,adolescence can provide a final chance for interventionto promote additional growth,with potential benefit interms of physical work capacity and for girls, ofdiminished obstetric risk.

� Linear growth may be limited by multiplesimultaneous nutrient deficiencies in manypopulations,

� which could explain that interventions withspecific individual nutrients (eg vitamin A ironspecific individual nutrients (eg, vitamin A, iron,zinc)

� increased pre-pregnancy weight and body stores ofnutrients, thus contributing to improved future pregnancyand lactation outcome,

� improved iron status with reduced risk of anaemia inpregnancy, low birth weight, maternal morbidity andmortality, and with enhanced work productivity andperhaps linear growth;

� improved folate status, with reduced risk of neural tubedefects in the newborn and megaloblastic anaemia inpregnancy.

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

� The overall nutritional status is better assessedwith anthropometry, in adolescence as well as atother stages of the life cycle. Anthropometry isthe single most inexpensive, non-invasive anduniversally applicable method of assessing bodyy pp g ycomposition, size and proportions

� Iodine deficiency disorders� Iodine deficiency disorders were widely prevalent

in most populations� Neuromotor and cognitive impairments of

variable degreesvariable degrees� Iodine deficiency is recognized as the most

common cause of preventable mental retardationin the world.

ZINC

� Evidence from supplementation trials suggests thatmarginal zinc nutriture may also limit skeletal growth

� zinc supplementation increased accretion of fat-freed h d li th i th th tmass and enhanced linear growth in those that were

stunted at baseline

CALCIUM� ½ of peak bone mass

accumulates in adolescence� AI for calcium = 1,300 mg

for ages 9–18 years� Inadequate calcium intake

Figure ��.�

can lead to low peak bonemass and is a risk factor forosteoporosis

TEENAGERS AND CALCIUM

� Teenagers have high calcium requirements.

� Around 50% of the adult skeleton is formed duringthe teenage years (RNI - boys 1000 mg/day, girls 800mg/day).

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

� A lack of calcium may have consequences for futurebone health e.g. increased risk of osteoporosis.

IRON

� Additional iron supports muscle growth andincreased blood volume� Adolescent females need iron to support

menstruation� RDA for iron� 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 ofenriched grains, lean meats, and legumes

IRON ABSORPTION� Good sources: meat (especially lean red meat), liver

and offal, green leafy vegetables, pulses (beans,lentils), dried fruit, nuts and seeds, bread andfortified breakfast cereals.

I f t (h i ) i dil� Iron from meat sources (heme iron) is readilyabsorbed by the body.

� Vitamin C helps the body to absorb iron from othersources (non-heme iron).

A HEALTHY DIET IS IMPORTANT FORTEENAGERS

Eating a healthy, balanced diet can:

• promote wellbeing by improving mood, energy and self-esteem tohelp reduce anxiety and stress;

• best concentration and performance;best co ce t at o a d pe o a ce;

• 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.

NUTRIENT 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 RDAsMalesAge (yrs) Kcal/kg Kcal/day Proteins g/kg Proteins

gm/day11-14 55 2500 1.0 4515-18 45 3000 0.9 59FemalesFemalesAge (yrs) Kcal/kg Kcal/day Proteins g/kg Proteins

gm/day11-14 47 2200 1.0 4615-18 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.

DIETARY RECOMMENDATIONS

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

Fruit and vegetables (33%)Bread, rice, potatoes,

pasta and other starchyfoods (33%)

Milk and dairy foods (15%)Meat, fish, eggs, beans

and other non-dairysources of protein (12%)

FOOD GUIDE PYRAMID

serving sizes can help you control the amount ofcalories, fat, saturated fat, cholesterol, sugar orsodium in your diet.

� Grains, Bread, Cereal and Pasta form the Base� Fruits and Vegetablesg� Lean Meat and Fish, Beans, Eggs� Dairy Products� Fats and Sweets

MACRONUTRIENTS

Macronutrient Recommendedintake

(% food energy)

Boys averageintake

(% food energy)

Girls averageintake

(% food energy)Fat 35% 35.4% 35.9%

- average intakes(Scottish NDNS and Survey of Sugar Intake data)

of which saturates 11% 14.2% 14.3%

Carbohydrate 50% 51.6% 51.1%

of which addedsugars (NMES)

11% 16.7% 16.4%

WHAT 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)

WHAT ABOUT SALT?

� NDNS survey results - average salt intakes aboverecommendations in teenagers:- Boys (11-14 years) 6.75 g/day

(15-18 years) 8.25 g/dayGi l ( 8 ) 5 5 /d- 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.

TEENAGERS AND ENERGY BALANCE� Levels of overweight and obesity are increasing: 35% of

teenagers (12-15 years) are classified as overweight orobese (Scottish Health Survey 2009).

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

� Restricted diets may lead to nutrient deficiencies andother health consequences.

�Teenagers of unhealthy weight may need guidance onlifestyle changes to help them achieve a healthy weight.

TEENAGERS – PHYSICAL ACTIVITY

� Physical activity through life is important formaintaining energy balance and overall health.

� At least 60 mins of moderate-intensity physical activityeach day is recommended.

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

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

DIET AND COGNITIVE ABILITY

• Food eaten at school can make up a substantialproportion of the diet and have a significant effect onfunctions such as learning, memory, informationprocessing and mood.

• Cognition represents a complex multidimensional setg p pof abilities and cognitive performance is affected bymany influencing factors.

• Nutritional effects are difficult to measure.

Stevenson J (2006) Dietary influences on cognitivedevelopment and behaviour in children Proct Nutr Soc

65(4):361-5.

Bellisle F (2004) Effects of diet on behaviour andcognition in children Br J Nutr 92 Suppl 2: S227-32.

GLYCEMIA

The brain appears to be sensitive to short-termfluctuations of glucose supply and therefore it

might be beneficial to maintain glycemia atadequate levels to optimise cognition.

EATING BREAKFAST

�Starting each day with breakfast will supplyenergy to the brain & body.

�Eating breakfast leads to improved energy andconcentration levels throughout the morning.

�Breakfast consumption may improve cognitivefunction related to performance in school.

� Improvement of memory

�Other benefits of breakfast include betternutrient intakes and weight control.

•Even mild dehydration (1-2%) can lead to headaches,irritability and loss of concentration. This level is notenough to cause feelings of thirst.

•The recommendation is to drink 6-8 glasses/day (1.2litres) to prevent dehydration People need to drink

FLUIDS AND HYDRATION

litres) to prevent dehydration. People need to drinkmore when the weather is hot or when they havebeen active.

•All drinks count in terms of fluid intake but thosewithout sugar are best between meals.

DIET AND IQ� Brain health depends on optimal intakes of nutrients

from the diet.

� Much speculation about the importance of long chainomega-3 fatty acids to behavioural and cognitivedevelopment, including IQ.

� Supplementation studies show the best outcomeobserved in children with learning disabilities.

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

DIET AND MOOD/BEHAVIOUR� There are a number of foods that have a

pharmacological effect in the body which affectsmood:

* caffeine;;* vaso-active amines, such as histamine;* tryptophan and serotonin.

� There is evidence to suggest that poor vitamin andmineral status may be associated with pooreducational attainment and antisocial behaviour.

FOOD ADDITIVES AND HYPERACTIVITY

� The Southampton study suggested that consumptionof mixes of certain artificial food colours and thepreservative sodium benzoate could be linked toincreased hyperactivity in some children. The coloursare:

sunset yellow FCF (E110)i li ll (E104)quinoline yellow (E104)

carmoisine (E122)allura red (E129)tartrazine (E102)ponceau 4R (E124)

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

Bateman B et al. 2007

EATING HABITS

� irregular eating habits� snacks generally provide ¼ of daily energy

intake� f t f d l f it t bl ilk� more fast food: less fruits, vegetables, milk� food choices are often dictated by peers

WHAT DO BOYS AND GIRLS WANT?

�boysys usually want togain muscle and get

tallertaller�Girls usually want to

control their weight

FOR GIRLS SOME ADDITION OFFAT IS NATURAL

� Need at least 17% bodyfat for normal periods

� Diet is a four letterword

� Improve eating habitsand activity – but don’tstarve or over exercise

BOYS MATURE LATER

� Growth spurt up to 2years later than girls

� Full muscle mass� Full muscle massdoesn’t develop untilone year after fullheight achieved

� Excess calories andprotein won’t speedthings up

MAKE 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 hascalories)

DURING A SPORTS EVENT

� Drink at least 2 cups ofwater before event

� Continue to drink 4� Continue to drink 4ounces every half hour

� Cool, not cold, water isbest

� Replace two cups offluid for every poundlost

EAT AT LEAST 5 SERVINGS OF FRUITS ANDVEGETABLES

� Lots of vitamins andminerals with fewcaloriescalories

� More fiber so you feelfull

� Portion size – palm ofgirl’s hand

EAT MORE WHOLE GRAIN BREADS ANDCEREALS

� Won’t cause weight gainif don’t eat too muchD di b d i� Depending on body size,will need 6-11 servings

� Portion size – the palmof a girl’s hand

GET ENOUGH PROTEIN BUT NOT TOO MUCH

� Get protein from leanmeat, fish and poultry

� Portion size palm of� Portion size – palm ofgirl’s hand

� Protein also comes fromdairy foods, dried beansand peas, peanut butter,nuts, seeds, soy foods

� Limit low nutrient foodswith lots of fat, sugarand sodium

� Make fast food a specialoccasion� choose grilled or broiled

meat, fish or poultry� choose side salads, baked

potatoes� choose milk, water or

juice

DISORDERED EATING

� Disordered eating patterns are more prevalent inadolescent females than males� May be linked with poor body image or low self-

esteem� Teens often adopt unhealthy habits such as� 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 eatingpatterns

ANOREXIA NERVOSA

� Refusal to maintain body weight over a minimalnormal weight.

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

� Denial of low body weight.

� In females, absence of at least 3 consecutivemenstrual cycles.

.

ANOREXIA NERVOSA:CLINICAL & LABORATORY FINDINGS

� LANUGO and EDEMA of the skin, bradycardiaand hypotension, constipation, normochromicanemia and leukopenia, hyponatremia,hypoglycemia, low hormonal levels (estrogen ortestosterone, LSH, FSH) but normal TSH and, , )increased cortisol

� SKELETAL CHANGE: OSTEOPENIA

ANOREXIA NERVOSASIGNS OF MALNUTRITION :

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

� Hollowing temporal muscles

� Wasting of the tigh muscles

� Easily plucked hairs

MEMO: the laboratory signs of malnutrition areHYPOALBUMINEMIA andHYPOPREALBUMINEMIA

TREATMENT FOR ANOREXIA NERVOSA

� Close supervision� Individual and family counseling� Self-acceptance� Time and patience� Nutrition therapy

BULIMIA NERVOSA

� Characterized episodes of binge eating alternating withpurging

� Female to male ratio 10:1� Some genetic factors may be involved, but and above all

cultural attitudes toward standards of physicalp yattractiveness

� 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)

BULIMIA NERVOSA: COMPLICATIONS� 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 oflaxatives can lead to constipation due to damage of thep gmyo-enteric plexus

� Abnormalities of the electrolytes:� Metabolic alkalosis due to frequent vomiting� HYPOKALEMIA present in 5% of the patients

BULIMIA NERVOSA: TREATMENT

� Replenish potassium losses

� Eventually I.V. fluids and lytes

� Monitor lytes frequently

and, of course

� Refer for psychiatric or psychologic counseling

TREATMENT FOR BULIMIA

� Eating only at mealtime� Portion control� Close supervision after eating� Psychological counseling

OBESITY:HEALTH CONSEQUENCES

� Cardiovascular disease risk� Type 2 diabetes (epidemic)� Hypertension� Hypertension� Orthopedic� Sleep apnea� Gall bladder disease/steatohepatitis� Psychosocial problems

BODY MASS INDEX

�Weight in kg divided by height in m2

�NORMAL BMI : 18 to 24 years of ageBMI < 18 : suspect malnutrition

BMI 24 to 30 : overweightBMI 30 to 40 : obesity

BMI above 40 = morbid obesity

OBESITY TREATMENTS

� Caloric restrictions: restrict fats to less than 30% of thetotal 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 5x weekly, and add someresistance exercise 2 or 3 times weekly (all under somesupervision).

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

FINAL COMMENTS

The recipe for effective weight loss is a combination of:� Motivation

� Physical activity� Caloric restriction

And all this with a lifelong adherenceAnd all this with a lifelong adherenceBUT

MEMO: Prevention of weight gain is the first step EVEN INCHILDREN