Moving out of the parental home may do more than change where young adults live; it may also mark a lasting shift toward poorer diet quality during one of the most formative stages of life.
Key takeaways
Drop in diet quality
Leaving the parental home was associated with a small decline in overall diet quality, with DASH scores falling by about one point after the transition.
Discretionary food intake increased
Discretionary food intake rose by about 1% when young people moved out, although that difference narrowed over time.
Diet-quality declines
The largest drop in diet quality was seen among those who moved in with a partner, while those living with friends or alone also experienced lower DASH scores.
Association, not causation
This was a longitudinal observational study, so the results show association rather than causation. The timing of leaving home was also inferred from follow-up reports rather than measured exactly.
Study: Moving out: The impact of leaving the parental home on diet quality trajectories among Australian adolescents and young adults (14-27 years). Image Credit: Zoriana Zaitseva / Shutterstock
In a recent study published in the journal Health and Place, researchers examined the impact of leaving the parental home on diet quality trajectories among adolescents and young adults in Australia.
Importance of Adolescent Nutrition and Health Outcomes
Good nutrition in adolescence is essential for establishing dietary habits for adulthood. Poorer diet quality is associated with adiposity, higher body mass index, greater fat mass, and cardiometabolic risk factors in adolescents, many of which persist into adulthood. The prevalence of obesity and overweight has increased worldwide, particularly in adolescents and children.
Higher intake of fruits and vegetables has been associated with lower obesity and cardiometabolic risk. In contrast, energy-dense foods and beverages are associated with weight gain, obesity, and poorer health outcomes.
Adolescence and early adulthood are still relatively understudied life stages, particularly in longitudinal research, despite being characterized by environmental and social transitions that may influence diet.
Study Design Using Raine Cohort Data
In the present study, researchers examined the trajectories of diet quality in young adults and adolescents and the impact of leaving the parental home. The Raine Study recruited pregnant females (generation 1) in Australia between 1989 and 1992; their children comprise the generation 2 cohort. Adolescents and young adults aged 14 to 27 years from the generation 2 cohort were included in this study.
Participants completed a food frequency questionnaire (FFQ) at follow-ups conducted at ages 14, 17, 20, 22, and 27 years. Diet quality was evaluated using two measures: discretionary food intake and the Dietary Approaches to Stop Hypertension (DASH) diet score. The DASH diet score was estimated at each follow-up and ranged from 0 to 80, with higher scores reflecting better diet quality.
Discretionary food intake was defined as the proportion of energy derived from discretionary foods and beverages. Discretionary foods and beverages were those that did not fit into the five core food groups, per the Australian Dietary Guidelines. Participants self-reported their living arrangements at 20, 22, and 27 years, while their primary caregivers reported them at 14 and 17 years.
Living arrangements included living with parents, a partner, friends, or alone. The age at which participants first reported any living arrangement other than living with their parents was considered the age at which they moved out of the parental home.
Participants could still move between non-parental living arrangements over time, but for the main analysis, first leaving the parental home was used as the transition point. Multi-level regression models were used to examine diet quality trajectories and the interactions with leaving the parental home and subsequent living arrangements.
Diet Quality and Living Arrangement Findings
The analytical sample included 1,135 participants. Almost all participants were living with parents at the 14- and 17-year follow-ups. At 20 and 22 years, most participants continued living in their parental home after starting employment; moreover, about half of the sample began higher education, and a majority continued living with parents.
By the 27-year follow-up, 29% of participants were still living in their parental home, while 63% had left the parental home by that follow-up. Among the total sample at 27 years, 46% were living with a partner. A U-shaped trajectory was observed for the DASH diet score, with the lowest score around age 20 years.
The DASH diet score decreased by about a point after leaving the parental home. By contrast, discretionary food intake increased by about 1% after moving out of the parental home.
People who lived with a partner, with friends, or alone showed an initial decline in their DASH diet score compared with those who lived in the parental home, with the largest reduction among those living with a partner.
Leaving the parental home to live alone initially reduced discretionary food intake by about 0.65%, while moving in with friends or a partner after leaving home increased it by about 1%. The interaction effect of time since leaving the parental home did not differ significantly by living arrangement.
Conclusions on Diet Changes After Leaving Home
In sum, moving out of the parental home was associated with a reduction in the DASH diet score; at this transition, discretionary food intake grew by about 1%. People who moved in with a partner had the largest reduction in diet score, while those living alone or with friends had a smaller decrease. Notably, the lower DASH diet score associated with leaving home appeared to persist over time, whereas the gap in discretionary food intake narrowed over time.
Overall, these results offer valuable insights into the factors that contribute to changes in diet quality from adolescence through early adulthood. A better understanding of factors shaping dietary behaviors could lead to the development of more effective public health strategies. However, the study was observational, so the findings show associations rather than proof that leaving home caused the dietary changes.
In addition, the exact timing of leaving home was inferred from follow-up reports rather than observed directly, dietary intake was self-reported, and some living-arrangement subgroups were small.
The authors also noted that the lack of a follow-up between ages 22 and 27 limited the precision of transition timing, particularly because many participants left the parental home during that interval.
Future studies should explore additional factors during this life stage, such as motivations for food choices, changes in income, time constraints, sex differences, and interactions with age.
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