K. Keenan

K. Keenan, A. Hipwell, Irene Tung, 2021, Journal of clinical child and adolescent psychology : the official journal for the Society of Clinical Child and Adolescent Psychology, American Psychological Association, Division 53.

Parental punishment and peer victimization as developmental precursors to physical dating violence involvement among girls.

A. Blokland, R. Loeber, K. Keenan, 2014, Journal of research on adolescence : the official journal of the Society for Research on Adolescence.

The moderating effects of traumatic stress on vulnerability to emotional distress during pregnancy

K. Keenan, A. Hipwell, S. Stepp, 2019, Development and Psychopathology.

S0954579419000531jra 673..686

K. Keenan, A. Hipwell, S. Stepp, 2020 .

Early predictors of sexually intimate behaviors in an urban sample of young girls.

R. Loeber, K. Keenan, A. Hipwell, 2010, Developmental psychology.

Concordance between maternal recall of birth complications and data from obstetrical records.

K. Keenan, A. Hipwell, A. Mohanty, 2017, Early human development.

Trajectories of Sexual Orientation from Adolescence to Young Adulthood: Results from a Community-Based Urban Sample of Girls.

K. Keenan, A. Hipwell, S. Stepp, 2018, The Journal of adolescent health : official publication of the Society for Adolescent Medicine.

Cardiac vagal control in response to acute stress during pregnancy: Associations with life stress and emotional support.

J. Jennings, N. Melhem, K. Keenan, 2021, Psychophysiology.

Validity of the Trier Social Stress Test in studying discrimination stress

K. Keenan, A. Hipwell, S. Stepp, 2020, Stress.

The Pittsburgh Girls Study: Overview and Initial Findings

R. Loeber, K. McTigue, K. Keenan, 2010, Journal of clinical child and adolescent psychology : the official journal for the Society of Clinical Child and Adolescent Psychology, American Psychological Association, Division 53.

Evidence of familial association between attention deficit disorder and major affective disorders.

S. Faraone, J. Biederman, M. Tsuang, 1991, Archives of general psychiatry.

Family-genetic and psychosocial risk factors in DSM-III attention deficit disorder.

S. Faraone, J. Biederman, M. Tsuang, 1990, Journal of the American Academy of Child and Adolescent Psychiatry.

Dorsomedial Prefrontal Activity to Sadness Predicts Later Emotion Suppression and Depression Severity in Adolescent Girls.

E. Forbes, J. Helm, K. Keenan, 2018, Child development.

Girls' pubertal development is associated with white matter microstructure in late adolescence

Amanda E. Guyer, Kevin J. Grimm, Rajpreet Chahal, 2018, NeuroImage.

Clinical Significance and Correlates of Disruptive Behavior in Environmentally At-Risk Preschoolers

Lauren S. Wakschlag, Kate Keenan, L. Wakschlag, 2001, Journal of clinical child psychology.

Hypothalamic–Pituitary–Adrenal Axis Activity in Childhood Predicts Emotional Memory Effects and Related Neural Circuitry in Adolescent Girls

E. Forbes, G. Shields, K. Keenan, 2021, Journal of Cognitive Neuroscience.

Associations between Race and Eating Disorder Symptom Trajectories in Black and White Girls

Yu Cheng, J. Wildes, K. Keenan, 2018, Journal of abnormal child psychology.

The relationship between body mass index, body dissatisfaction, and eating pathology in sexual minority women.

K. Keenan, Andrea B. Goldschmidt, A. Hipwell, 2019, The International journal of eating disorders.

Preadolescent Clues to Understanding Depression in Girls

K. Keenan, A. Hipwell, 2005, Clinical child and family psychology review.

Reciprocal Influences Between Girls’ Conduct Problems and Depression, and Parental Punishment and Warmth: A Six year Prospective Analysis

R. Loeber, K. Keenan, M. Stouthamer-Loeber, 2008, Journal of abnormal child psychology.

The effect of prenatal docosahexaenoic acid supplementation on infant outcomes in African American women living in low-income environments: A randomized, controlled trial

K. Keenan, A. Hipwell, Amy M. Hoffmann, 2016, Psychoneuroendocrinology.

Modulation of prenatal stress via docosahexaenoic acid supplementation: implications for child mental health.

K. Keenan, A. Hipwell, 2015, Nutrition reviews.

Differences in childhood body mass index between lesbian/gay and bisexual and heterosexual female adolescents: A follow-back study

K. Keenan, K. Wroblewski, A. Hipwell, 2018, PloS one.

Impact of sedentary behavior and emotional support on prenatal psychological distress and birth outcomes during the COVID-19 pandemic

Rosalind J Wright, A. Alshawabkeh, M. Karagas, 2023, Psychological Medicine.

Subtyping dietary restraint and negative affect in a longitudinal community sample of girls.

M. McCloskey, K. Keenan, E. Chen, 2009, The International journal of eating disorders.

The Environmental Influences on Child Health Outcomes (ECHO)-Wide Cohort

Emily A. Knapp, Emily A Knapp, Casper G Bendixsen, 2023, American journal of epidemiology.

Sex-Dependent Cognitive Performance in Baboon Offspring Following Maternal Caloric Restriction in Pregnancy and Lactation

Jesse S. Rodriguez, T. Q. Bartlett, M. Nijland, 2012, Reproductive Sciences.

Pregnancy and Lactation Sex-Dependent Cognitive Performance in Baboon Offspring Following Maternal Caloric Restriction in

Peter W. Nathanielsz, Jesse S. Rodriguez, T. Q. Bartlett, 2012 .

The Impact of Adolescent Sexual Harassment Experiences in Predicting Sexual Risk-Taking in Young Women

K. Keenan, K. Wroblewski, A. Hipwell, 2019, Journal of interpersonal violence.

The impact of childhood temperament on the development of borderline personality disorder symptoms over the course of adolescence

R. Krueger, K. Keenan, A. Hipwell, 2014, Borderline Personality Disorder and Emotion Dysregulation.

A developmental framework for distinguishing disruptive behavior from normative misbehavior in preschool children.

Margaret J. Briggs-Gowan, B. Leventhal, A. Carter, 2007, Journal of child psychology and psychiatry, and allied disciplines.

Emotion Regulation and Loss of Control Eating in Community-Based Adolescents

K. Keenan, J. Lavender, Andrea B. Goldschmidt, 2017, Journal of abnormal child psychology.

Depression screening may not capture significant sources of prenatal stress for Black women

K. Keenan, A. Hipwell, Kimberley Mbayiwa, 2023, Archives of Women's Mental Health.

Transgenerational associations between maternal childhood stress exposure and profiles of infant emotional reactivity

K. Keenan, A. Hipwell, Irene Tung, 2019, Development and Psychopathology.

S0954579419000324jra 887..898

K. Keenan, A. Hipwell, Irene Tung, 2019 .

Capturing the dynamic nature of stress exposure in the Pittsburgh Girls Study

K. Keenan, R. Krafty, A. Hipwell, 2021, SSM - Population Health.

Brief report: Parsing the heterogeneity of adolescent girls' sexual behavior: relationships to individual and interpersonal factors.

R. Loeber, K. Keenan, T. Chung, 2011, Journal of adolescence.

Temperament and Parenting during the First Year of Life Predict Future Child Conduct Problems

J. Rodgers, B. D’Onofrio, I. Waldman, 2008, Journal of abnormal child psychology.

Growth in Alcohol Use as a Developmental Predictor of Adolescent Girls’ Sexual Risk-Taking

K. Keenan, T. Chung, A. Hipwell, 2012, Prevention Science.

Preconception stress exposure from childhood to adolescence and birth outcomes: The impact of stress type, severity and consistency

K. Keenan, A. Hipwell, Irene Tung, 2023, Frontiers in Reproductive Health.

DEVELOPMENT OF DISRUPTIVE BEHAVIORS IN YOUNG CHILDREN: A PROSPECTIVE POPULATION-BASED COHORT STUDY.

J. Séguin, K. Keenan, C. Normand, 2012, Infant mental health journal.

The Development of Opposition-Defiance During Toddlerhood: A Population-Based Cohort Study

K. Keenan, R. Baillargeon, G. Cao, 2012, Journal of developmental and behavioral pediatrics : JDBP.

Chronic family adversity and early child behavior problems: a longitudinal study of low income families.

M. Dunn, K. Keenan, D. Shaw, 1994, Journal of child psychology and psychiatry, and allied disciplines.

Conduct Disorder in Girls: A Review of the Literature

R. Loeber, K. Keenan, S. Green, 1999, Clinical child and family psychology review.

DSM-III-R disorders in preschool children from low-income families.

K. Keenan, D. Shaw, J. Giovannelli, 1997, Journal of the American Academy of Child and Adolescent Psychiatry.

Gender differences in physical aggression: A prospective population-based survey of children before and after 2 years of age.

R. Tremblay, M. Boivin, S. Côté, 2007, Developmental psychology.

Mind the gap: assessing impairment among children affected by proposed revisions to the diagnostic criteria for oppositional defiant disorder.

K. Keenan, 2012, Journal of abnormal psychology.

Autobiographical Memory as a Predictor of Depression Vulnerability in Girls

K. Keenan, Susan Klostermann, A. Hipwell, 2011, Journal of clinical child and adolescent psychology : the official journal for the Society of Clinical Child and Adolescent Psychology, American Psychological Association, Division 53.

Sex Differences in Young Children Who Meet Criteria for Attention Deficit Hyperactivity Disorder

C. Hartung, E. Willcutt, W. Pelham, 2002, Journal of clinical child and adolescent psychology : the official journal for the Society of Clinical Child and Adolescent Psychology, American Psychological Association, Division 53.

Adolescent girls' neural response to reward mediates the relation between childhood financial disadvantage and depression.

E. Forbes, K. Keenan, A. Guyer, 2015, Journal of child psychology and psychiatry, and allied disciplines.

Maternal activity, anxiety, and protectiveness during moderate nutrient restriction in captive baboons (Papio sp.)

T. Q. Bartlett, M. Nijland, P. Nathanielsz, 2018, Journal of medical primatology.

Parsing the relations between SES and stress reactivity: examining individual differences in neonatal stress response.

K. Keenan, D. Gunthorpe, D. Grace, 2007, Infant behavior & development.

Observational Assessment of Preschool Disruptive Behavior, Part II: validity of the Disruptive Behavior Diagnostic Observation Schedule (DB-DOS).

Margaret J. Briggs-Gowan, James L. Burns, B. Leventhal, 2008, Journal of the American Academy of Child and Adolescent Psychiatry.

Prenatal betamethasone exposure has sex specific effects in reversal learning and attention in juvenile baboons.

Nicole R. Zürcher, Jesse S. Rodriguez, T. Q. Bartlett, 2011, American journal of obstetrics and gynecology.

Performance of juvenile baboons on neuropsychological tests assessing associative learning, motivation and attention

Nicole R. Zürcher, Kate Keenan, Peter W. Nathanielsz, 2010, Journal of Neuroscience Methods.

Timing and tempo: Exploring the complex association between pubertal development and depression in African American and European American girls.

Kevin J. Grimm, K. Grimm, K. Keenan, 2014, Journal of abnormal psychology.

Poor nutrition during pregnancy and lactation negatively affects neurodevelopment of the offspring: evidence from a translational primate model.

Kate Keenan, Peter W Nathanielsz, Jesse S. Rodriguez, 2013, The American journal of clinical nutrition.

Emotion Dysregulation as a Risk Factor for Child Psychopathology

K. Keenan, 2006 .

Phenotyping stress exposures related to perinatal health disparities.

K. Keenan, A. Hipwell, Kimberley Mbayiwa, 2020, Developmental psychobiology.

Evidence for the Continuity of Early Problem Behaviors: Application of a Developmental Model

K. Keenan, D. Shaw, J. Giovannelli, 1998, Journal of Abnormal Child Psychology.

Observational Assessment of Preschool Disruptive Behavior, Part I: reliability of the Disruptive Behavior Diagnostic Observation Schedule (DB-DOS).

Margaret J. Briggs-Gowan, James L. Burns, B. Leventhal, 2008, Journal of the American Academy of Child and Adolescent Psychiatry.

A double-blind placebo controlled study of desipramine in the treatment of ADD: III. Lack of impact of comorbidity and family history factors on clinical response.

R. Baldessarini, S. Faraone, J. Biederman, 1993, Journal of the American Academy of Child and Adolescent Psychiatry.

Mother's Childrearing History and Current Parenting: Patterns of Association and the Moderating Role of Current Life Stress

L. Wakschlag, K. Keenan, Carrie L. Hill, 2006, Journal of clinical child and adolescent psychology : the official journal for the Society of Clinical Child and Adolescent Psychology, American Psychological Association, Division 53.

Antecedents of preschool children's internalizing problems: a longitudinal study of low-income families.

K. Keenan, D. Shaw, J. Giovannelli, 1997, Journal of the American Academy of Child and Adolescent Psychiatry.

Subthreshold symptoms of depression in preadolescent girls are stable and predictive of depressive disorders.

Xin Feng, K. Keenan, A. Hipwell, 2008, Journal of the American Academy of Child and Adolescent Psychiatry.

Psychological Well-Being Across the Perinatal Period: Life Satisfaction and Flourishing in a Longitudinal Study of Young Black and White American Women

K. Keenan, A. Hipwell, Irene Tung, 2023, Journal of Happiness Studies.

Theoretical, Developmental & Cultural Orientations of School-Based Prevention Programs for Preschoolers

Marisha L. Humphries, K. Keenan, 2006, Clinical child and family psychology review.

Risk and Protective Factors of Child

J. Coie, R. Tremblay, R. Loeber, 2012 .

Risk and Protective Factors of Child Delinquency. OJJDP Child Delinquency Bulletin Series.

J. Coie, R. Tremblay, R. Loeber, 2003 .

Childhood Risk Factors for Child Delinquency and Later Violent Juvenile Offending

J. Coie, R. Tremblay, R. Loeber, 2003 .

Delinquency in Adolescent Girls

K. Keenan, P. Tolan, A. Hipwell, 2014, Criminal justice and behavior.

Testing Descriptive Hypotheses Regarding Sex Differences in the Development of Conduct Problems and Delinquency

J. Rodgers, B. D’Onofrio, I. Waldman, 2006, Journal of abnormal child psychology.

Early risk factors and pathways in the development of early disruptive behavior problems

Elizabeth B. Owens, K. Keenan, D. Shaw, 1996, Development and Psychopathology.

The relation between parent depressive symptoms and neural correlates of attentional control in offspring: A preliminary study

Christopher S. Monk, C. Monk, K. Phan, 2017, Psychiatry Research: Neuroimaging.

Neural Reward Processing Mediates the Relationship between Insomnia Symptoms and Depression in Adolescence.

E. Forbes, K. Keenan, A. Guyer, 2016, Sleep.

Emerging depression is associated with face memory deficits in adolescent girls.

Kevin J. Grimm, K. Grimm, D. Pine, 2011, Journal of the American Academy of Child and Adolescent Psychiatry.

Lack of assertion, peer victimization, and risk for depression in girls: testing a diathesis-stress model.

Xin Feng, K. Keenan, A. Hipwell, 2010, The Journal of adolescent health : official publication of the Society for Adolescent Medicine.

The association of pain and depression in preadolescent girls: moderation by race and pubertal stage.

K. Keenan, A. Hipwell, Amanda Hinze, 2009, Journal of pediatric psychology.

Can a valid diagnosis of disruptive behavior disorder be made in preschool children?

L. Wakschlag, K. Keenan, 2002, The American journal of psychiatry.

The development of aggression in toddlers: A study of low-income families

K. Keenan, D. Shaw, 1994, Journal of abnormal child psychology.

Brain structure and parasympathetic function during rest and stress in young adult women

E. Forbes, K. Keenan, A. Guyer, 2021, Brain Structure and Function.

Age of onset, symptom threshold, and expansion of the nosology of conduct disorder for girls.

R. Loeber, K. Keenan, K. Wroblewski, 2010, Journal of abnormal psychology.

Callous-Unemotional Behaviors in Young Girls: Shared and Unique Effects Relative to Conduct Problems

R. Loeber, K. Keenan, D. Pardini, 2007, Journal of clinical child and adolescent psychology : the official journal for the Society of Clinical Child and Adolescent Psychology, American Psychological Association, Division 53.

Characteristics of girls with early onset disruptive and antisocial behaviour.

R. Loeber, H. White, K. Keenan, 2002, Criminal behaviour and mental health : CBMH.

Evidence for the independent familial transmission of attention deficit hyperactivity disorder and learning disabilities: results from a family genetic study.

S. Faraone, J. Biederman, L. Seidman, 1993, The American journal of psychiatry.

Impact of oppositional defiant disorder dimensions on the temporal ordering of conduct problems and depression across childhood and adolescence in girls.

Xin Feng, R. Loeber, K. Keenan, 2011, Journal of child psychology and psychiatry, and allied disciplines.

Substance Use and Sexual-Minority Status: Examining the Mediating Roles of Stress and Emotion Dysregulation in Young Adult Women

K. Keenan, T. Chung, Connor J. McCabe, 2021, Clinical psychological science : a journal of the Association for Psychological Science.

Interaction between conduct disorder and its comorbid conditions: Effects of age and gender

Kate Keenan, Rolf Loeber, R. Loeber, 1994 .

Editorial introduction: three longitudinal studies of children's development in Pittsburgh: the Developmental Trends Study, the Pittsburgh Youth Study, and the Pittsburgh Girls Study.

D. Farrington, R. Loeber, B. Lahey, 2002, Criminal behaviour and mental health : CBMH.

Emotion Regulation and Loss of Control Eating in Community-Based Adolescents

K. Keenan, J. Lavender, Andrea B. Goldschmidt, 2016, Journal of Abnormal Child Psychology.

Call for Action: High Rates of Depression in the Pediatric Celiac Disease Population Impacts Quality of Life

K. Keenan, Hilary Jericho, S. Guandalini, 2021, JPGN reports.

A Transactional Model of Infant Still-Face Response and Maternal Behavior During the First Year.

K. Keenan, E. Moses-Kolko, A. Hipwell, 2019, Infancy : the official journal of the International Society on Infant Studies.

TEACHER AND OBSERVER RATINGS OF YOUNG AFRICAN AMERICAN CHILDREN'S SOCIAL AND EMOTIONAL COMPETENCE.

Marisha L. Humphries, L. Wakschlag, K. Keenan, 2012, Psychology in the schools.

Timing of Violence Exposure and Girls’ Temperament Stability From Childhood to Adolescence

K. Keenan, A. Hipwell, Irene Tung, 2023, Journal of interpersonal violence.

Predicting adolescent postpartum caregiving from trajectories of depression and anxiety prior to childbirth: a 5-year prospective study

K. Keenan, E. Moses-Kolko, A. Hipwell, 2016, Archives of Women's Mental Health.

Neonatal Physiological Regulation is Associated With Perinatal Factors: A Study of Neonates Born to Healthy African American Women Living In Poverty.

M. Byrne, K. Keenan, S. Jacob, 2009, Infant mental health journal.

Association of maternal dopamine transporter genotype with negative parenting: evidence for gene x environment interaction with child disruptive behavior

E. Cook, W. Pelham, B. Lahey, 2010, Molecular Psychiatry.

Opposition-Defiance in the Second Year of Life: A Population-Based Cohort Study.

K. Keenan, Gregory D. Sward, R. Baillargeon, 2011, Infancy : the official journal of the International Society on Infant Studies.

Defining the “Disruptive” in Preschool Behavior: What Diagnostic Observation Can Teach Us

Margaret J. Briggs-Gowan, B. Leventhal, D. Cicchetti, 2005, Clinical child and family psychology review.

Effects of Adolescent Childbearing on Maternal Depression and Problem Behaviors: A Prospective, Population-Based Study Using Risk-Set Propensity Scores

J. Murray, K. Keenan, A. Hipwell, 2016, PloS one.

African American Preschoolers' Social and Emotional Competence at School: The Influence of Teachers and Mothers

Marisha L. Humphries, K. Keenan, J. Strickland, 2014 .

Mother-Teacher Agreement on Preschoolers’ Symptoms of ODD and CD: Does Context matter?

K. Keenan, J. Hopkins, J. Strickland, 2012, Journal of abnormal child psychology.

A family-genetic study of girls with DSM-III attention deficit disorder.

S. Faraone, J. Biederman, M. Tsuang, 1991, The American journal of psychiatry.

Preschool Children's Observed Disruptive Behavior: Variations Across Sex, Interactional Context, and Disruptive Psychopathology

Margaret J. Briggs-Gowan, A. Carter, L. Wakschlag, 2012, Journal of clinical child and adolescent psychology : the official journal for the Society of Clinical Child and Adolescent Psychology, American Psychological Association, Division 53.

Trajectories of Depression and Anxiety Symptoms in Adolescent Girls: A Comparison of Parallel Trajectory Approaches

R. Loeber, K. Keenan, T. Olino, 2014, Journal of personality assessment.

Alcohol Use Trajectories Before and After Pregnancy Among Adolescent and Young Adult Mothers.

K. Keenan, T. Chung, R. Krafty, 2020, Alcoholism, clinical and experimental research.

Police contacts, arrests and decreasing self‐control and personal responsibility among female adolescents

Feifei Ye, K. Keenan, A. Hipwell, 2018, Journal of child psychology and psychiatry, and allied disciplines.

Testing an equifinality model of nonsuicidal self-injury among early adolescent girls

K. Keenan, K. Wroblewski, A. Hipwell, 2014, Development and Psychopathology.

Development of an Empirically Based Preventive Intervention for Depression in Preadolescent African American Girls

Tasha M. Brown, K. Keenan, K. Grant, 2016, Prevention Science.

A Longitudinal Study of Differences in Perceived Parenting Practices Between Sexual Minority and Heterosexual Girls.

K. Keenan, A. Hipwell, J. Berona, 2021, Journal of research on adolescence : the official journal of the Society for Research on Adolescence.

Longitudinal patterns and predictors of suicidal ideation in African American adolescents.

W. L. Robinson, K. Keenan, Leonard A. Jason, 2023, American journal of community psychology.

Factor structure of the Outness Inventory in a sample of Black and White lesbian and bisexual young adult women

K. Keenan, A. Hipwell, Irene Tung, 2022, Journal of gay & lesbian mental health.

Non-suicidal self-injury and suicidal ideation as predictors of suicide attempts in adolescent girls: a multi-wave prospective study.

Lori N. Scott, P. Pilkonis, K. Keenan, 2015, Comprehensive psychiatry.

Social Support Coping for African American Adolescents: Effect of a Culturally Grounded Randomized Controlled Trial Intervention

K. Keenan, Christopher R. Whipple, L. Jason, 2023, Prevention Science.

Are There Stable Factors in Preadolescent Girls’ Externalizing Behaviors?

R. Loeber, K. Keenan, D. Pardini, 2009, Journal of abnormal child psychology.

Parent-based diagnosis of attention deficit disorder predicts a diagnosis based on teacher report.

S. Faraone, J. Biederman, K. Keenan, 1990, Journal of the American Academy of Child and Adolescent Psychiatry.

Psychiatric diagnosis in preschool children. Authors' replies

J. McClellan, M. Monuteaux, J. Biederman, 2003 .

Developmental Models of Depression, Externalizing Problems, and Self-regulatory Processes: Integrated Data Analysis Across Four Longitudinal Studies of Youth

Elizabeth A. Stormshak, E. Westling, K. Keenan, 2022, Prevention Science.

Suicide in African American Adolescents: Understanding Risk by Studying Resilience.

K. Keenan, LaRicka R Wingate, Christopher R. Whipple, 2021, Annual review of clinical psychology.

Subthreshold symptoms of depression in preadolescent girls are stable and predictive of depressive disorders.

Xin Feng, K. Keenan, A. Hipwell, 2008, Journal of the American Academy of Child and Adolescent Psychiatry.

The Pittsburgh Girls Study: Overview and Initial Findings

Examining links between sexual risk behaviors and dating violence involvement as a function of sexual orientation.

K. Keenan, A. Hipwell, S. Stepp, 2013, Journal of pediatric and adolescent gynecology.

Examining two prevailing models of loss of control eating among community-based girls

K. Keenan, J. Lavender, Andrea B. Goldschmidt, 2017, Obesity.

Brief report: Differences in self-injurious thoughts and behaviors between sexual minority and heterosexual adolescent girls

K. Keenan, A. Hipwell, S. Stepp, 2021, Journal of Gay & Lesbian Mental Health.

Delinquency in Adolescent Girls

K. Keenan, P. Tolan, A. Hipwell, 2014, Criminal justice and behavior.

The influence of motherhood on neural systems for reward processing in low income, minority, young women

M. Phillips, E. Forbes, H. Chase, 2016, Psychoneuroendocrinology.

Poor nutrition during pregnancy and lactation negatively affects neurodevelopment of the offspring: evidence from a translational primate model.

Nicole R. Zürcher, Jesse S. Rodriguez, T. Q. Bartlett, 2013, The American journal of clinical nutrition.