Adolescent Nutrition: Needs and Behaviors

Nutrition Needs and Maturation

• Nutrition requirements should be based on biological maturity instead of chronological age
• Biological maturity impacts nutrient needs more directly
• Nutrition is tightly linked to growth and development rates
• Individuals of the same age can vary significantly
• Assessing biological maturity offers insights into planning

Unhealthy Adolescent Eating Behaviors

• Frequent dieting and meal skipping are unhealthy behaviors
• These behaviours, along with high fat and sugar consumption, can lead to nutritional deficiencies and health issues

Impact of Changes on Nutrition

• Biological, psychosocial, and cognitive changes affect nutritional status and needs
• Adolescent growth spurts, evolving identities, and cognitive abilities influence dietary choices

Independence and Eating Habits

• A desire for independence might cause health-compromising eating habits
• Adolescents could experiment with unhealthy diets due to peer influence or personal beliefs

Health-Compromising Eating Behaviors

• Excessive dieting or fad diets are eating behaviors that compromise health, negatively impacting health via nutritional deficiencies and metabolic imbalances

Health-Enhancing Eating Behaviors

• Regular physical activity and healthful eating habits enhance health
• Balanced eating, physical activity, and an interest in a healthy lifestyle are health-enhancing behaviours

Start of Puberty

• Sexual maturation is the biological event that marks the start of puberty
• Puberty includes sexual maturation and changes in body composition

Assessing Adolescent Needs

• Sexual maturation (biological age) is crucial when assessing growth, development, and nutritional requirements
• Sexual maturation stages offer a more precise measure of an adolescent's development and nutrient demands compared to chronological age alone

Sexual Maturation Rating (SMR)

• The Sexual Maturation Rating (SMR), or Tanner Stages, assesses pubertal maturation degree
• SMR serves as an essential tool for evaluating physical progression through puberty based on secondary sexual characteristics

SMR 1

• SMR 1 indicates prepubertal growth and development
• SMR 1 signifies the initial stage of development before puberty-related changes or milestones

Menarche

• Menarche marks the onset of the first menstrual period, usually 2-4 years after initial breast bud development
• Menarche marks a significant milestone in female sexual maturation

Restrictive Diets in Females

• Severely restrictive diets may delay or slow growth in adolescent females
• Inadequate nutrient intake from restrictive diets can compromise growth by limiting essential nutrients

Peak Growth in Males

• Peak velocity of linear growth in males occurs during SMR 4, ending with facial hair around 14.4 years
• Peak linear growth corresponds to SMR 4, concluding when facial hair begins to emerge

Linear Growth in Males

• Linear growth in males continues until roughly 21 years old

Body Fat Changes in Females

• Body fat increases by about 120% in females during adolescence
• Females experience a body fat increase that facilitates menarche

Body Fat for Menarche

• Menarche needs 17% body fat in adolescent females

Weight Gain in Females

• During peak weight gain, females gain about 18.3 pounds per year related to puberty

Body Fat Changes in Males

• Body fat typically decreases to around 12% in males during adolescence

Bone Mass

• Adolescents accrue around half of their adult bone mass
• Calcium and vitamin D are important nutrients

Psychological Development

• Adolescents achieve a sense of personal identity
• Adolescents develop a moral compass and imagine professional careers

Psychosocial Development

• Middle adolescence occurs between 15-17 years old

Peer Influence

• Peer influence can improve or worsen an adolescent's diet
• The need to fit in with peers may positively or negatively affect a growing adolescent's health

Environmental Factors

• Food availability, preferences, and cost are major influences

Adolescent Eating Influences

• Personal/individual, environmental, and macrosystem factors are levels of influence

Consequences of Busy Lifestyles

• A busy lifestyle can result in less time for meals, which leads to snacking and meal skipping

Vegetarian Diets

• About 4% of adolescents report following a vegetarian diet

Motivation for vegetarianism

• Moral, ethical, and/or health concerns can influence adolescents to adopt vegetarianism

Vegan Diets

• Vegan diets exclude all animal products, including meat, dairy, eggs, and sometimes honey

Nutrient Deficiencies in Vegan Adolescents

• Vegan adolescents may have inadequate calcium, zinc, and iron intakes
• Vegan adolescents may require alpha-linolenic acid supplementation

Typical Dietary Patterns

• Most adolescents consume inadequate fruits and vegetables
• Adolescent diets often lack these components

Calorie Proportions

• Adolescents get 32% of their calories from fat and 21% from added sugars

Heightened Needs

• Adolescents need more nutrients, energy, and nutrients to support increases in body mass and maturation

Dietary Recommendations

• Professional judgement ensures the provision of adequate nutritional information to adolescents

Consequences of Low Protein

• Low protein intake can result in reductions in linear growth, delays in sexual maturation, and reduced lean body mass
• Protein can assist adolescents to grow at a normal rate

AMDR for Fat

• Fat should account for 25-35% of total calories to assist adolescents

Calcium Intake

• Adequate calcium is critical during adolescence to ensure peak bone mass

Calcium Absorption

• Early adolescence results in about four times more calcium absorption than early adulthood

Iron Deficiency Anemia

• Iron deficiency anemia is less frequent but found almost exclusively in females

Heme vs Nonheme Iron

• Heme iron is highly bioavailable, found in animal products/hemoglobin, while nonheme iron is less so.

Vitamin D

• Vitamin D plays a role in calcium and phosphorus absorption, important for bone formation

Folate Deficiency

• Megaloblastic anemia (low red blood cell count) may derive from severe folate deficiency

Folate Intake

• Adequate folate intake is important, particularly for adolescent females, and reduces birth defects like spina bifida

Smoking and Vitamin V

• Smoking increases the need for vitamin C
• Vitamin C helps improve breathing and prevent chronic obstructive pulmonary disease (COPD)

Physical Activity Recommendations

• Adolescents should be physically active every day for at least 60 minutes
• Regular physical activity helps with staying healthy

Explore nutritional needs tied to biological maturity, not just age. Understand unhealthy eating behaviors like dieting and skipping meals and how biological, psychosocial, and cognitive shifts affect nutrition. Also learn how the desire for independence impacts eating habits.