15- Adolescence Flashcards
Definition of adolescence
The period between the start of puberty and adulthood
- Early adolescents: 10-14
- Late adolescents: 15-19
- Early adulthood: 20-24
Define puberty
The physical transformation from child to adult. It includes: sexual maturation, increased height and weight, completion of skeletal growth, changes in body composition.
Timespan of female sexual maturation
Starts from 8-12 years old; 5 year process
How does body composition change in female adolesents?
Peak weight gain occurs after peak height gain and before menarche. Greater increases in fat mass (120%) than lean mass (44%); increasing fat mass proportion to lean mass.
How does body composition change in male adolescents?
Peak weight gain and peak height gain occur simultaneously. Increased lean body mass and decreased fat mass (increased proportion of lean body mass).
Why has the age of menarche decreased?
Because BMI has increased over time. Leptin from adipose tissues signal the start of puberty by removing GnRH suppression.
When does leptin increase in puberty (males and females)
Females: leptin increases seen 6 months before menarche; related to glutofemoral fat
Males: increases in leptin precede puberty, but then leptin concentrations decline
What are some consequences of very early onset of menses?
- Social and behavioural
- Increased risk of: metS/PCOS and breast cancer
What describes a change in cognitive development?
A shift from concrete to abstract thinking
At what stage of adolescence is peer influence the strongest?
Middle adolescence. Peer influence is strong during early adolescence, decreses in later adolescence, and early adulthood is marked by independence.
How should health messages be directed towards adolescents?
They should consider: cognitive and social development, behavioural characteristics, youth culture and trends
3 factors affecting eating behaviours in adolescence:
- Individual - biological changes, attitudes, beliefs, preferences, self efficacy
- Environment - family/home, school, peers, norms
- Macrosystems - availability, production, distribution, media, policy
What nutrients are decreased when breakfast is skipped?
Iron, calcium, fibre, fruit
What is the quality in terms of following CFG recommendations in adolescent diets
75% are in the requires improvement category; 25% in poor quality; none in good quality
What percentage of adolescents don’t reach grain recommendations?
Around 1/3 of female adolescents.
What percentage of adolescents do not meet vegetable and fruit requirements?
Around 45-62% of males (better intake with age)
Around 60-68% of females (better intake with age)
- More males meet requirements than females
Percentage of adolescents who do not meet milk and alt recommendations
46-65% of male
65-83% of females
Why don’t adolescents eat healthy foods?
- Lack of availability and not enough variety
- Healthy foods offeed at school are unappealing
- Easy access to unhealthy foods
- Social pressure to eat unhealthy foods (parent
Barriers to healthy eating in young adults
- Unhealthy diets of friends and family
- Unhealthy foods are cheap
- Preference for unehealthy food
- Lack of time, facilities, knowledge, skills
- etc.
How does energy intake recommendations compare between adolescence and adulthood?
Higher energy intake (absolute and per kg) for adolescents.
Fibre intake for M and F 14-18 years
F: 26
M: 38
AMDR for 14-18yr
PRO: 10-30
Fats: 25-35
CHO: 45-65
Peak calcium accretion rate age
M: 14
F: 12.5
What percentage of calcium accretion occurs in the 3-4 years of adolescence?
40%
Other than calcium and vit D intake, what is important for calcium retention?
Physical activity
When are iron requirements the highest?
M: peak growth rate
F: after first menses
When does the DRI for F iron increase?
14 according to Health Canada, but actually at the age of menses
How do nutritional recommendations change for adolescents during pregnancy vs preganant adults?
- Pregnant adolescents require higher energy and some minerals: calcium, phosphorus, Mg, Zn, iron
- (Due to demands for maternal growth and pregnancy)
- Require greater nutrition support
How does social development change from Early adolescence to early adulthood
Early adolescence: Body image and aware of sexual awareness - peer influence
Middle: Emotional and social independence, make decisions for self - peer influence
Late: Personal identity + beliefs, social confidence, - less peer
Early adulthood - Completion of independence, adult roles and responsibility
