Jennifer B Unger

University of Southern California | USC · Institute for Health Promotion and Disease Prevention Research

While adverse childhood experiences (ACE) are well-documented predictors of maladaptive behaviors in adulthood, including risky sexual behaviors (RSB), the influence of acculturation in this association remains unknown. Although Hispanics are a rapidly growing population in the United States and are disproportionately affected by adverse sexual hea...

Rationale: Specific cannabis products may differentially increase risk of initiating non-cannabis illicit drug use during adolescence. Objective: To determine whether ever- and poly-use of smoked, vaporized, edible, concentrate, or blunt cannabis products are associated with subsequent initiation of non-cannabis illicit drug use. Methods: High...

The potential impact of the COVID-19 pandemic on young people’s mental and physical health is of increasing concern. We examined the levels of internalizing and externalizing problem behavior and physical complaints before and during the COVID-19 pandemic in Germany. Data came from a repeated cross-sectional study on child and youth health in schoo...

Objective To estimate the extent to which drinking to cope with the COVID-19 pandemic and experiencing pandemic-related life stressors are associated with alcohol use escalation among young adults. Methods Respondents in Los Angeles, CA, USA (N = 2,130) completed prospective cohort study surveys before (baseline; October 2018–November 2019; mean a...

e-Cigarette companies use cartoon images to market their products, and exposure to this marketing strategy may lead to increased risk for adolescent e-cigarette use. This study examined the effects of cartoon marketing image exposure on perceived expectations of benefits and risks of e-cigarette use, and willingness to buy e-cigarette-related produ...

Adverse childhood experiences (ACE) have a strong association with alcohol and drug use; however, more research is needed to identify protective factors for this association. The present study assesses the longitudinal impact of ACE on problematic alcohol and drug use and the potential moderating effect of perceived social support. Data (n = 1404)...

Background: E-cigarette companies use YouTube to foster brand awareness, market their products, and interact with current and future tobacco users. However, research on the official YouTube channels of e-cigarette companies is limited. This study determined the themes of, and degree of user engagement with, videos posted to the official channels o...

The present article proposes an extension of the concept of adverse childhood experiences (ACEs) to apply to crisis migration – where youth and families are fleeing armed conflicts, natural disasters, community violence, government repression, and other large-scale emergencies. We propose that adverse events occurring prior to, during, and followin...

Objectives: Despite the widespread availability of COVID-19 vaccines in the United States, vaccine hesitancy remains high among certain groups. This study examined the correlates of being unvaccinated among a sample of students attending a single university (N = 2900) during the spring and summer of 2021, when the campus had been closed for over a...

Few studies have described the association between lifetime smoking exposures and young-onset breast cancer (YOBC) risk by BC subtypes including the human epidermal growth factor receptor 2 (HER2) subtype. This study explored associations between lifetime cumulative cigarette smoking exposure from both secondhand smoke (SHS) and personal smoking ex...

Background: Memes, images or videos with text overlay that embody a concept or belief about the contemporary society, are endemic to Internet culture, are popular among youth and diffuse rapidly across social media platforms. E-cigarettes and vaping have grown in popularity in the era of Internet culture however there is little research describing...

Vape shops specialize in sales of e-cigarettes and related products. This study examines whether vape shops adapted their products and services in response to changes in federal and state policies that affect the tobacco retail environment between 2014–2022. In this multicohort study, four waves of study data were used to examine the trends in prod...

Immigration continues to be a prevalent process that impacts children and adolescent development. The context of the immigration experience, from pre-immigratory factors in the heritage country, to the in-transit journey, and lastly, settlement factors, are conduits of both challenges and opportunities for children and adolescent. From a risk and r...

Background Lack of education and training on caring for patients with substance use disorder (SUD) is common among healthcare providers, often resulting in clinicians feeling unprepared to treat patients with SUD. Objectives This study explored resident physicians’ experiences with SUD education throughout medical school and residency and qualitat...

ABSTRACT Introduction Local e-cigarette sales restrictions (ESRs) may impact e-cigarette use. This study examined the associations between living in localities with various ESR policies and changes in e-cigarette use among young adults in Los Angeles (LA) County, California, USA. Methods Data were from a cohort of LA County young adults (18–21 year...

Exposure to social media and its content featuring tobacco products is associated with e-cigarette use among adolescents. This study measured the association between frequency of Instagram, TikTok and YouTube use and exposure to tobacco-related content on each of these platforms with e-cigarette ever-use, current (past 30-day) use and initiation am...

Youth have been the focus of electronic vapor product (EVP) prevention efforts though young adults had similar increases in current EVP use from 2015–2019. This study tested messages to reduce EVP use in young adults. Eight messages on vaping related harms and addictiveness combined with themes on social use and flavors were selected for inclusion...

New oral nicotine products (ONPs; nicotine pouches, gums, lozenges, and gummies), which are regulated as nonmedicinal tobacco products in the U.S., have flavors and other characteristics that previously attracted young adults to e-cigarettes. Whether young adults’ interest in ONPs differs by e-cigarette use status and quit-vaping motivation is unkn...

Modern oral nicotine products (ONPs; nontherapeutic nicotine pouches, gums, lozenges, and gummies) may be perceived in ways that could promote uptake in nonvapers, dual use with e-cigarettes, or use to quit vaping. In this cross-sectional digital remote survey of 1,460 respondents aged 21-24 from Southern California, we examined beliefs about ONPs...

BACKGROUND AND OBJECTIVES Flavored non-tobacco oral nicotine products (eg, nicotine pouches and nontherapeutic nicotine gum, lozenges, tablets, gummies), are increasingly marketed in the United States. Prevalence of non-tobacco oral nicotine product use among adolescents is unknown. METHODS We calculated prevalence of ever and past 6-month use of...

BACKGROUND After the United States Food and Drug Administration (FDA) restricted characterizing flavors in tobacco products, ‘ice’ hybrid-flavored e-cigarettes, which combine a cooling flavor with fruit or other flavors (e.g., banana ice), have recently emerged on the market. Like menthol, ‘ice’ flavors produce a cooling sensory experience. However...

Background The US Food and Drug Administration (FDA) recently restricted characterizing flavors in tobacco products. As a result, ice hybrid–flavored e-cigarettes, which combine a cooling flavor with fruit or other flavors (eg, banana ice), emerged on the market. Like menthol, ice-flavored e-cigarettes produce a cooling sensory experience. It is un...

Purpose To evaluate the association between lifetime personal cigarette smoking and young-onset breast cancer (YOBC; diagnosed <50 years of age) risk overall and by breast cancer (BC) subtype, and whether risk varies by race or socioeconomic position (SEP). Methods Data are from the Young Women’s Health History Study (YWHHS), a population-based ca...

American Indian Alaska Native (AIAN) youth have disproportionately higher rates of commercial tobacco product use compared to other racial and ethnic groups in the U.S. These rates underscore a need for commercial tobacco product cessation interventions that are culturally informed. This project studied the development, implementation, and some imp...

Introduction Young adults new to tobacco (including e-cigarettes) are at an increased risk of e-cigarette use after e-cigarette exposure. This study examined the association between noticing e-cigarette advertising features and perceived product appeal among non-tobacco-using young adults. Methods A sample of non-tobacco-using young adults (ages 1...

Although authorized mRNA COVID-19 vaccines (BNT162b2 by BioNTech/Pfizer and mRNA-1273 by Moderna) significantly reduce morbidity and mortality, recent evidence suggests that immunity wanes over time, and that a booster dose could further reduce COVID-19 transmission and severe illness. However, research examining attitudes on booster willingness in...

Background: The packaging and marketing of nicotine gums, lozenges, and pouches can influence users' perceptions about which products are evidence-based for tobacco cessation and which are designed for nicotine maintenance-which could keep people nicotine dependent. Lucy, a company that produces flavored nicotine gums, lozenges, and pouches, could...

Given the rapidly changing political rhetoric and policies concerning immigration, and the likely impact of this rhetoric on immigrants' adjustment, it is essential to understand the experiences of recently arrived immigrant individuals and families. This article describes methods to recruit and retain recently arrived Hispanic families in longitud...

COVID-19 vaccines have been available for over a year, yet 26% of U.S. young adults remain unvaccinated. This study examines racial and ethnic disparities in young adult vaccine hesitancy and attitudes/beliefs that mediate disparities in vaccine hesitancy. Young adults (n = 2041;Mean[SD]:21.3[0.7] years-old) from a Los Angeles, CA, USA cohort were...

Background Children age 5–11 became eligible for COVID-19 vaccination in November 2021 in the United States, but vaccine uptake in this age group remains low. Understanding reasons why parents are hesitant to vaccinate their children may provide critical insights to help protect children from COVID-19 infection. This study examines factors associat...

Although adverse childhood experiences (traumatic events such as maltreatment and household dysfunction) are associated with increased risk for sleep difficulties among adults, the association between adverse childhood experiences and poor sleep health among young adult college populations is understudied. This study examined the adverse childhood...

Introduction: E-cigarette use in the United States has continued to increase since its introduction a decade ago, but reasons for e-cigarette use are still poorly understood. Although several studies have examined popular concepts in e-cigarette users’ health beliefs on social media, connections between these concepts and their relationships with o...

Introduction. Walking is associated with lower risk of premature death. Studies have tested a variety of walking interventions; however, results have varied substantially. The limited understanding of when to deliver different types of prompts is a key barrier to developing a just-in-time adaptive intervention (JITAI) for walking. This study aimed...

Objective This study examined characteristics associated with being unvaccinated among a sample of university staff and faculty prior to university campus reopening for in-person learning in 2021. Methods Staff and faculty responded to an email invitation to complete an online survey. Survey questions included demographic data (race/ethnicity, age...

Objectives: To determine the effects of electronic cigarettes (e-cigarettes) as a therapeutic intervention compared to nicotine replacement therapy (NRT) on nicotine abstinence. Methods: Two authors independently searched the PubMed, Embase, PsycInfo and Cochrane Central Register of Controlled Trials databases for articles published up to and in...

It is established that higher pre-diagnostic circulating androgen and estrogen levels are associated with increased breast cancer risk in premenopausal and postmenopausal women. Pooled analyses in postmenopausal women report higher androgen and estrogen levels in current heavy cigarette smokers compared to nonsmokers. However, evidence among premen...

Social media platforms offer an opportunity for targeted health communication ads to improve tobacco and cannabis prevention efforts. This study described tobacco and cannabis-related ads targeted towards adolescents and young adults on Snapchat. Data comprised of publicly available tobacco (n=70) and cannabis-related (n=64) ads from Snapchat in 20...

Background Adverse childhood experiences (ACE), including maltreatment and household dysfunction, are consistent predictors of health compromising behaviors in adulthood. While most ACE studies have focused on adults, there is an emerging body of research focusing on young adulthood. Methods This review describes research focused on the relationsh...

Oral nicotine pouches may appeal to young adult current nicotine/tobacco users interested in alternative forms of nicotine that lack pulmonary exposure, but may also appeal to young adult non-users of nicotine/tobacco products. We used data from a 2020 remote digital survey of an ongoing cohort study of young adults from Southern California (aged 1...

Background Exposure to visual posts featuring e-cigarette products on social media is associated with increased e-cigarette use among US adolescents. Instagram is the largest source of e-cigarette social media marketing, where influencers—for example, bloggers, brand ambassadors—post promotional materials. This study analysed the network of e-cigar...

The present study was designed to examine the extent to which, in a sample of 873 Hispanic college students, daily levels of, and variability in, well-being would mediate the predictive effects of culturally related stressors (discrimination, negative context of reception, and bicultural stress) on internalizing and externalizing symptoms 11 days l...

Background: School-based COVID-19 testing is a potential strategy to limit COVID-19 transmission among youth in congregate settings such as schools, sports programs, and summer camps. The purpose of this study is to evaluate the feasibility and effectiveness of frequent rapid antigen testing at a supervised distance-learning setting for elementary...

Background School-based COVID-19 testing is a potential strategy to facilitate the safe reopening of schools that have been closed due to the pandemic. This qualitative study assessed attitudes toward this strategy among four groups of stakeholders: school administrators, teachers, parents, and high school students. Methods Focus groups and interv...

Purpose Cannabis use among adolescents may have detrimental effects and use among this age group is increasing. It is important to understand how expansion of laws permitting cannabis sales may impact adolescent use. Much of the current research has explored how state-level policy decisions may impact adolescents’ use behaviors; however, there is a...

Introduction: Given the prevalence of electronic vapor product (EVP) use among young people in the US, there is a need for effective vaping education campaigns. This study tested 32 images for liking and perceived effectiveness (PE) to identify optimal images for a messaging campaign. Method: Images were selected from current campaigns, warning...

Introduction: Machine learning presents a unique opportunity to improve electronic cigarette (vaping) monitoring in youth. Here we built a random forest model to predict frequent vaping status among Californian youth and to identify contributing factors and vulnerable populations. Methods: In this prospective cohort study, 1,281 ever-vaping twelfth...

Objective Acculturation discrepancy occurs when the rate of host culture acquisition and/or heritage culture retention between non-native parents and their children diverges. The resulting conflict may exacerbate mental health conditions in already vulnerable populations. The present study examined discrepancies between Hispanic and Anglo-American...

Adolescent hope can promote the emotional and behavioral well‐being of Latinx families. Positive family functioning may foster adolescent hope, whereas cultural stress may compromise adolescent hope and well‐being. We examined how adolescent hope changed over time, and whether cultural stress and family functioning predicted emotional and behaviora...

This study describes key topics of discussions on Twitter at the intersection of vaping and COVID-19 and documents public reactions to announcements from authoritative health agencies. Twitter posts containing vaping and COVID-19-related terms were collected from 1 December 2019 to 3 May 2020 (n = 23,103 posts). Text classifiers and unsupervised ma...

Background School-based COVID-19 testing is a potential strategy to facilitate the safe reopening of schools that have been closed due to the pandemic. This qualitative study assessed attitudes toward this strategy among four groups of stakeholders: school administrators, teachers, parents, and high school students. Methods Focus groups and intervi...

Mindfulness-based interventions (MBIs) may offer a means for Latinx families to ameliorate stress, enhance emotion regulation, and foster social support. We assessed pilot data from Latinx parents in Eastside Los Angeles (n = 27) matched with their children aged 10–16 (n = 32) to determine whether participation in a community-derived MBI was associ...

Background Adverse Childhood Experiences (ACE) are associated with substance use in adolescence and adulthood. However, there is a lack of longitudinal research examining the effect of ACE on substance use trajectories from adolescence through emerging adulthood. Objective This study examined the role of ACE in substance use trajectories among His...

Objectives In February 2020, the US Food and Drug Administration issued a guidance restricting the sales and distribution of cartridge-based e-cigarettes with flavours other than tobacco and menthol. Disposable devices were exempt from this guidance. This study examined the prevalence of disposable pod use and flavour preference compared with refil...

Young adults (YA) who report viewing pro-tobacco and cannabis marketing are at increased risk for using tobacco and cannabis. However, there is a growing diversity of tobacco and cannabis products on the market, as well as methods for marketing them. Prevalence of, and sociodemographic differences in, YA’s recall of various types of tobacco and can...

The prevalence of cigarette smoking in the United States has been declining for over 50 years among all racial/ethnic groups. However, this progress could be stalled or even reversed by the increasing popularity of electronic cigarettes (e-cigarettes). Hispanics have experienced tobacco-related health disparities resulting from early age of cigaret...

In the United States, a substantial proportion of the adult population (36% of women and 34% of men) from all socioeconomic and ethnic backgrounds report experiencing intimate partner violence (IPV) over the life course. Family risk factors have been linked to adolescent and young adult IPV involvement, yet few studies have examined the effect of m...

Purpose Adverse childhood experiences (ACEs) are associated with substance use, how cultural factors influence this association for Latinx youth is unknown. This study uses longitudinal data to examine associations of cultural factors, ACEs and substance use among Latinx young adults. Methods Latinx youth (N = 1179) completed surveys from a longit...

Purpose The COVID-19 pandemic has exacerbated several existing health disparities in the U.S. Sexual and gender minority (SGM) health disparities may also be widening during the pandemic, though few studies have assessed this question. This study examined SGM young adult disparities in health-related behaviors to cope with isolation during the pand...

Background: Tobacco price promotions may prompt tobacco trials among youth. We assessed whether receiving price promotions for any tobacco, cigarettes, e-cigarettes and cigars was associated with product use progression. Methods: The analysis included a nationally representative sample of youth never tobacco users (aged 12–16; n=9405) from wave 4...

Background: In response to the recent government restrictions, flavored JUUL products, which are rechargeable closed-system electronic cigarettes (e-cigarettes), are no longer available for sale. However, disposable closed-system products such as the flavored Puff Bar e-cigarette continues to be available. If e-cigarette consumers simply switch be...

Purpose: Ethnic disparities in childhood cancer survivor (CCS) mental health have been identified, although prior survivorship research has focused predominantly on non-Hispanic/Latinx (H/L) white survivors. Methods: This study examined the association of acculturation with depressive symptoms and wellbeing among 582 young adult H/L CCS recruited t...

The current study was designed to address gaps in the existing literature by examining the role of discrimination and familism values as predictors of multiple forms of prosocial behaviors across time in a sample of recent immigrant Latino/a adolescents. Participants were 302 recent immigrant Latino/a adolescents (53.3% male; average age 14.51 year...

Introduction E-cigarette users typically initiate vaping with flavoured e-liquids. People who vape flavours tend to underestimate the harm of vaping. We examined the inter-relationship between flavour preference, vaping for cessation purposes, e-cigarette dependence, e-cigarette harm perception and purchase/use intention, given a hypothetical flavo...

Introduction Modified risk tobacco product (MRTP) claims for heated tobacco products (HTPs) that convey reduced exposure compared with conventional cigarettes may promote product initiation and transition among young people. We assessed the effects of a hypothetical MRTP claim for HTPs on young adults’ intention and perceptions of using HTPs and wh...

The present study investigated the prevalence and co-occurrence of addictions to tobacco, alcohol, other drugs, food/eating, the internet, texting, video games, shopping, love, sex, exercise, work, and gambling among American Indian (AI) youth in California. As with previous work in other cultural groups, the most prevalent addictions were love, in...

Introduction: A holistic public health surveillance approach can help capture the public's tobacco and marijuana-related attitudes and behaviors. Using publicly available data from Twitter, this is one of the first studies to describe key topics of discussions related to each intersection (e-cigarette, combustible tobacco, and marijuana) of the Tr...

Although there is a substantial body of work focusing on the processes underlying cultural identity in general, less is known regarding how these processes might operate within the context of Latinx families. Moreover, among the limited research that has included the adolescent and caregiver cultural identity, most of the research has primarily foc...

1) Background: The heated tobacco product IQOS, by Philip Morris International, is now available in over 55 countries, including the United States. Social media sites such as Twitter are often used to promote or discuss tobacco products, though prior research has not examined how IQOS is presented on Twitter. (2) Methods: This study collected and c...

Background The prevalence of electronic-cigarette (e-cigarette) product placement in music videos is on the rise and currently unregulated. This promotional activity is concerning given the popularity of music videos among young adults. Aims We examined associations between self-reported levels of exposure to music videos with any e-cigarette prod...

Introduction Young adults’ e-cigarette use is associated with perceptions that e-cigarettes are less harmful or addictive than cigarettes, socially acceptable, and appealing. This study developed and tested vaping educational messages addressing these factors: 1) Harm Perceptions, 2) Addictiveness, 3) Social Use, and 4) Flavors. Methods Two messag...

Daily diary studies allow for examining the day-to-day dynamic experiences of biculturalism. The present study used a 12-day daily diary dataset collected with 873 Hispanic college students. Our goal was to (a) identify two distinct forms of dynamic daily processes of linguistic biculturalism (bicultural levels and bicultural fluctuations) and (b)...

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Introduction Adolescent electronic cigarette (e-cigarette) use is increasing worldwide, raising concerns about its impact on youth development. Remote acculturation may influence the e-cigarette use cognitions of youth in Mexico by influencing their media use, thereby contributing to their e-cigarette use susceptibility. This study examined whether...