Adolescnet Nutrition Flashcards
Nutrition needs in a time of change
Biological, psychosocial and cognitive changes affect nutrition status
Rapid growth increases nutrient needs
Desire for independence may cause adoption of health compromising eating behaviours
Eg. Excessive dieting, meal skipping, unconventional nutrition supplements, dad diets, substance use/ abuse
Sexual maturation rating
Consistent but great individual variation in age of maturatartion
Biological age should be used to assess growth and development rather than chronological age (tanner stages)
As much as 50% of ideal adult body weight is gained during adolescence
Maturation and growth of females
Menarche occurs 2-4 years after initial development of breast buds
Age of menarche ranges from 9-17 years
Peak linear growth occurs approx 6-12 months prior to menarche
Severely restricted diets may delay or slow growth
Peak weight gain follows linear growth spurt by 3-6 months - gain of 8kg per year, slowing at time of menarche but continuing into late adolescence
44% increase in lean body mass
120% increase in fat
Approx 17% body fat required for menarche to occur
Approx 25% body fat needed to maintain normal menstrual cycle
Maturation and growth of males
Show great variation in chronological age when sexual maturation takes place
Peak velocity of linear growth occurs during SMR 4 and ends with appearance of facial hair at approx 14.4
Linear growth continues through adolescence ceasing at age 21
Peak weight gain occurs at same time, approx 9kg per year
Body fat decreases to 12%, half of bone mass is accrued in adolescence
Factors affecting eating
Peer influence Parent modelling Food availability, preferences and cost- pocket money for hot chips rather than healthy smoothie Personal and cultural beliefs Mass media Body image
Eating away from home, eating meals in front of the tv, little time to sit down for a meal
Adequacy of nutrition intake in adolescents
Poor intake of dairy, grains, fruits and vegetables
Less than 1 serve if veg
Less than 1 serve of fruit
Adequate intake of grains but whole grains less than adequate
32% of calories from fat and 21% from added sugars
Energy requirements
For increase in lean body mass, skeletal mass and body fat
Energy and nutrient needs during adolescence exceed those of any other point in life
Influenced by activity level, BMR, pubertal growth and development, sex, physical activity decline
Protein requirements
Required to maintain exisiting LBM, for growth of new LBM
Low protein intakes related to reductions in linear growth, delays in sexual maturation, reduced LBM
Poor nutrient intake
Folate Vit A, B6, C and e Iron and zinc Magnesium Phosphorous and calcium Fibre
Calcium
Critical to ensure peak bone mass
Absorption highest around menarche
Highest in males around early adolescence
Soft drink consumption displaces nutrient dense beverages
Iron requirements
Increased needs: Rapid rate of linear growth Increase in blood volume Menarche in females Iron needs greatest after menarche Iron needs greatest during growth spurt
Vitamin D
Essential role in facilitating intestinal absorption of calcium and phosphorous
Essential for bone formation
Synthesised by the body via skin exposure and ultraviolet B days of sunlight
Food sources: fatty fish, fish oils, egg yolks of Henderson fed vi D fortified feed
Folate requirements
Required for DNA, RNA and protein synthesis
Severe folate deficiency leads to megablastic anaimean
Severe deficiency rare but inadequate folate status appears to be more common
Folate added to fortified foods is better absorbed than folate from natural foods
Adequate folate intake for female adolescents reduces incidence of birth defects like Spina bifida
Vit c
Marginally adequate among adolescents
Involved in the synthesis of collagen and other connective tissue
Acts as an antioxidant
Smoking increases need for vitamin C
Veg diets
4% follow veg diet Cultural or religious beliefs Moral or ethical concerns Health beliefs To restrict fat and or calories A means of independence from family
Well planned veg diets can offer many health advantages, best when small amounts of animal derived foods are included
Vegans at risk of protein, calcium, zinc, iron, vit d, b6 and b12 inadequate intake
Physical activity
Should participate in at least 60 mins of moderate to vigorous pa a day
Should not spend more than 2 hours on electronic media
Improved aerobic endurance and muscle strength Reduced risk of obesity Greater bone density Positive self esteem and self concept Lower levels of anxiety and stress
Affected by confidence in ability to exercise
Positive perception of activity or sports
Positive attitude toward activity
Peer and family support
Availability of safe and convenient places to play, sports equipment, transportation to sports or fitness programs
Factors increasing risk of overweight and obesity
Having one or more overweight parents From a low income family Increased prevalence among indigenous and Pacific Islanders Mobility limiting conditions Inadequate physical activity Diet high in calories, sugars and fat
Nutrition education and counselling
Involve adolescent in decision making process
Encourage adolescent to suggest ways to change
Work toward only 1-2 goals per counselling session
Could utilise technology for optimal outcomes
Substance use
Tobacco increases vit C needs
Alcohol can replace nutritious foods and bevs
Illicit drugs may increase risk of disordered eating
Substance use may lead to depleted iron, vit c and thiamin stores
Reduced apprentice decreases intake of range of nutrients
Iron deficiency
Determined by low serum iron, plasma ferritin and transferring saturation
Iron deficiency more frequency
Anaemia
Determined by simple and inexpensive haemoglobin or haematocritic levels
Indicated more advanced stage of iron deficiency
Less frequent but almost exclusively females
Eating disorders
Most common chronic illness for younger females
Adolescence with diabetes have a 2-4 fold increased risk of developing an eating disorder
70% of adolescent girls have body dissatisfaction
Cystic fibrosis
Interferes with lung function
Causes decreased absorption of nutrient
Malabsorption due to lack of pancreatic enzymes
Dietary consideration: calories and protein increases 2 to 4 fold, enzyme taken with meals to aid digestion, frequent meals and snacks, fat soluble vitamin supplements, gastronomy feeding at night may be needed to boost energy intake
Phenylketonuria
Inborn error of metabolism
Body lacks enzymes needed to metabolise phenylalanine
Require intervention to manage breakdown of dietary proteins
Diet is adequate on vitamins, minerals, protein fat and calories
Nutrients are often provided in liquids rather than solid form
Dietary treatment includes avoiding meats, eggs, dairy products, nuts and soy beans
