Contents l.NTRODUCTION… 1.1 Adolescents:Who are they?.............. 1.2 Increasing focus on adolescent health and well-being................. …2 1.3 Objectives and content of the paper. 2.ADOLESCENCE PROVIDES A WINDOW OF OPPORTUNITY FOR NUTRITION ............. 2.1 Adolescence is a timely period for the adoption and consolidation of sound dietary habits …7 2.2 Improving adolescents'nutrition behaviours is an investment in adult health ............. 2.3 There is potential for correcting nutritional inadequacies and perhaps even for catch-upgT0wth…8 2.4 Nutrition intervention in adolescent girls may contribute to breaking the vicious cycle of intergenerational malnutrition,poverty and chronic disease..9 2.5 Reaching households and communities through adolescents...............10 3.ADOLESCENCE IS A PERIOD OF NUTRITIONAL VULNERABILITY.11 3.1 Conceptual framework for the analysis of nutritional problems in adolescence.....11 3.2 Nutritional problems in adolescence.13 3.2.1 Undernutrition,stunting and consequences in adolescence...14 3.2.1.1 Overview on malnutrition in adolescence...............................14 3.2.1.2 Malnutrition delays physical growth and maturation.....16 3.2.1.3 Stunting and delayed maturation compound risk of adolescent pr gnancy.l6 3.2.1.4 Malnutrition reduces work capacity .......... .16 3.2.2 Iron deficiency anaemia and other widespread micronutrient deficiencies.......17 3.2.2.1 Iron deficiency and anaemia.17 3.2.2.2 Vitamin A deficiency20 3.2.2.3 lodine deficiency disorders......... 20 3.2.2.4 Micronutrient deficiencies and bone disease ..............2o 3.2.3 Obesity and other nutrition-related chronic diseases..2. 3.2.31 3.2.3.2 Cardiovascular disease risks.24 3.2.3.3 Nutrition,gout and gallstones......... 25 3.2.3.4 Nutrition and cancer26 3.2.4 Tooth decay,a nutrition-related problem in adolescence........... .27 3.3 Early pregnancy,a well-documented factor of health and nutritional risk in adolescent grlS…,27 3.3.1 Maternal mortality and morbidity28 3.3.2 Low birth weight and prematurity29 3.3.3 Lactational performance ... 29 3.3.4 Socioeconomic consequences and correlates............. 30 3.4 Lifestyle and eating patterns,major threats to adolescents'nutritional status......31 3.4.1 Typical eating patterns and intakes of adolescents.31 3.4.2 Commercial,cultural and psychosocial influences on eating patterns........32 N UTR IT I O N I N A DO L ES C E N C E /iiN U T R I T I O N I N A D O L E S C E N C E /iii Contents 1. INTRODUCTION ............................................................................................................................... 1 1.1 Adolescents: Who are they? ..................................................................................................... 1 1.2 Increasing focus on adolescent health and well-being .......................................................... 2 1.3 Objectives and content of the paper ....................................................................................... 4 2. ADOLESCENCE PROVIDES A WINDOW OF OPPORTUNITY FOR NUTRITION .................. 7 2.1 Adolescence is a timely period for the adoption and consolidation of sound dietary habits ......................................................................................................................................... 7 2.2 Improving adolescents’ nutrition behaviours is an investment in adult health .................. 7 2.3 There is potential for correcting nutritional inadequacies and perhaps even for catch-up growth ....................................................................................................................... 8 2.4 Nutrition intervention in adolescent girls may contribute to breaking the vicious cycle of intergenerational malnutrition, poverty and chronic disease ................................. 9 2.5 Reaching households and communities through adolescents ............................................ 10 3. ADOLESCENCE IS A PERIOD OF NUTRITIONAL VULNERABILITY ..................................... 11 3.1 Conceptual framework for the analysis of nutritional problems in adolescence .............. 11 3.2 Nutritional problems in adolescence .................................................................................... 13 3.2.1 Undernutrition, stunting and consequences in adolescence ............................... 14 3.2.1.1 Overview on malnutrition in adolescence ............................................. 14 3.2.1.2 Malnutrition delays physical growth and maturation .......................... 16 3.2.1.3 Stunting and delayed maturation compound risk of adolescent pregnancy ................................................................................................. 16 3.2.1.4 Malnutrition reduces work capacity ...................................................... 16 3.2.2 Iron deficiency anaemia and other widespread micronutrient deficiencies ....... 17 3.2.2.1 Iron deficiency and anaemia ................................................................... 17 3.2.2.2 Vitamin A deficiency ............................................................................... 20 3.2.2.3 Iodine deficiency disorders ..................................................................... 20 3.2.2.4 Micronutrient deficiencies and bone disease ........................................ 20 3.2.3 Obesity and other nutrition-related chronic diseases .......................................... 22 3.2.3.1 Obesity ..................................................................................................... 22 3.2.3.2 Cardiovascular disease risks.................................................................... 24 3.2.3.3 Nutrition, gout and gallstones ................................................................ 25 3.2.3.4 Nutrition and cancer ............................................................................... 26 3.2.4 Tooth decay, a nutrition-related problem in adolescence .................................... 27 3.3 Early pregnancy, a well-documented factor of health and nutritional risk in adolescent girls.......................................................................................................................................... 27 3.3.1 Maternal mortality and morbidity ........................................................................ 28 3.3.2 Low birth weight and prematurity ........................................................................ 29 3.3.3 Lactational performance ........................................................................................ 29 3.3.4 Socioeconomic consequences and correlates........................................................ 30 3.4 Lifestyle and eating patterns, major threats to adolescents’ nutritional status .................. 31 3.4.1 Typical eating patterns and intakes of adolescents............................................... 31 3.4.2 Commercial, cultural and psychosocial influences on eating patterns ............... 32