lecture - 13

Question 1

puberty

Answer 1

physical transformation from child to adult

Question 2

what age does sexual maturation start for females, how long does it last

Answer 2

8-12
- 5 year process

Question 3

what hormone is key in sexual maturation in females, and what are the roles (3)

Answer 3

estrogen
- reproductive organ maturation
- secondary sex characteristics
- causes menarche (first period)

Question 4

In females,between what SMR stages is the height peak, what is this associated with

Answer 4

2-3
- around same time as menarche

Question 5

In males, between what SMR stages is the height peak

Answer 5

3 and 4

Question 6

what hormone is key in male sexual maturation, and its functions (4)

Answer 6

testosterone
- increases testicular volume
- changes to external genitalia
- sperm production
- secondary sex characteristics

Question 7

when is sexual maturation in males, how long does it last

Answer 7

9.5 to 13.5
- 4 years in length

Question 8

what hormone signals onset menstruation and how

Answer 8

leptin from adipose tissue, it removes suppression of GnRH

Question 9

what is associated with earlier puberty in girls

Answer 9

increased BMI

Question 10

body composition changes in females

Answer 10

• peak weight gain after peak heigt and before menarche
• increase in both lean and fat mass
• more fat mass > than lean mass

Question 11

body composition changes in males

Answer 11

• peak weight gain coincides with peak height velocity
• increased lean mass and decreased fat mass

Question 12

role of leptin in females

Answer 12

increase in leptin speeds menarche by about 6 months
related to glutofemoral fat

Question 13

role of leptin in males

Answer 13

increases in leptin speeds initiation of puberty, leptin then declines

Question 14

consequences of early age first menses

Answer 14

• social and behavioural impact
• increased risk of PCOS and breast cancer

Question 15

modern day eating day behaviours

Answer 15

eating more meals away from home

Question 16

snacks are usually higher in ____, _____ and _____ than meal foods

Answer 16

sugar, fat and sodium

Question 17

what is the typical range of snacks per day

Answer 17

1-7 snacks per day
25-33 % of energy

Question 18

what meal is often skipped

Answer 18

breastfast

Question 19

what meal of the day is usually more nutrient dense than other meals

Answer 19

breakfast

Question 20

skipping breakfast can lead to decreased

Answer 20

calcium, protein etc

Question 21

why don’t adolescents eat healthy foods

Answer 21

• availability
• no parents to watch over you and tell you what to eat
• more unhealthy food available at school, arena/sports
• not taught how to pack healthy lunch
• marketing
• unappealing healthy foods at school

Question 22

barriers to healthy eating

Answer 22

• unhealthy diet of friends and fam
• cheapness and widespread availability
• preference for unhealthy foods
• lack of self regulation

Question 23

adolescents energy intake recommendations

Answer 23

• higher than adults
• energy needs for maintenance
• estimated energy expenditure: height, weight, age etc

Question 24

what does low intake lead to

Answer 24

impaired growth
delayed sexual maturation

Question 25

what does high energy intake lead to

Answer 25

overweight/obesity

Question 26

male fibre RDA 14-18 yrs

Answer 26

38g

Question 27

female fibre RDA 14-18yrs

Answer 27

26g

Question 28

peak calcium accretion in males and females

Answer 28

females: 12.5 males: 14.0

Question 29

what percent of bone mass accumulation happens during adolescence

Answer 29

40% of total lifetime during 3-4 years

Question 30

when is the highest req. of iron for males and females

Answer 30

males: during peak growth rate females: after first menses

Question 31

what three main factors affect eating behaviour

Answer 31

- individual - environment - macrosystems

Question 32

pattern of grain servings for male and female as they age

Answer 32

females: decreasing grain servings as they age males: eating below in grain servings from 14-18 yrs old only

Question 33

patter of fruit and veg for males and females as they age

Answer 33

females and males: consuming more as they age

Question 34

what age is peak bone mass and fracture zone

Answer 34

peak: 18-20s fracture: 50-70+

Question 35

body image during adolescence, what is poor body image associated with

Answer 35

strongly related, - its associated with dieting behaviour, disordered eating and clinical eating disorderes

Question 36

what is the pattern of body sanctification in Canadian youth

Answer 36

body satisfaction decreases as they age

Question 37

what are the clinical eating disorders, what is the cause of them

Answer 37

- anorexia nervosa - bulimia nervosa - binge eating disorder the causes are multifactorial

Question 38

what concerns are there with substance use in adolescence

Answer 38

- suppressed appetite and low intake - decreased nutrient absorption and increased losses - higher req. of some nutrients - less money for food

Question 39

concerns with adolescent pregnancy

Answer 39

- poor maternal and fetal outcomes: anemia, postpartum weight retention - stillbirth, neonatal mortality, LBW - low rates of breastfeeding - poor diet quality

Question 40

what nutrition concerns are there for adolescent pregnancy

Answer 40

- adolescent is still growing so it needs nutrients for growth - pregnancy and lactation needs (two competing demands: her growth and babies growth)

Question 41

recommendations for adolescent pregnancy

Answer 41

same in regular pregnancy but higher energy and some minerals - need more support ex; dietitian, resources