Australian Longitudinal Study Finds Moving Out of Parental Home Triggers Lasting Decline in Diet Quality for Young Adults

Australian researchers find that moving out of the parental home leads to a lasting decline in diet quality and a spike in junk food consumption for young adults.

By: AXL Media

Published: Mar 24, 2026, 4:59 AM EDT

Source: Information for this report was sourced from Health and Place

The Formative Transition to Independent Living

Adolescence and early adulthood represent critical windows for establishing dietary habits that often persist throughout a lifetime. While moving out of the parental home is a celebrated rite of passage, new research published in the journal Health and Place suggests it may also mark a downward shift in nutritional health. By analyzing data from the long-running Raine Study in Australia, researchers tracked 1,135 participants to see how their "Dietary Approaches to Stop Hypertension" (DASH) scores changed as they transitioned to independence. The findings indicate that the environmental and social shifts accompanying a move away from parents can undermine the consumption of core food groups, potentially increasing long-term cardiometabolic risks.

Tracking the U-Shaped Trajectory of Diet Quality

The researchers observed a distinct U-shaped trajectory in diet quality, with the lowest nutritional scores typically occurring around the age of 20. Upon leaving the parental home, participants' DASH scores—which measure intake of fruits, vegetables, and whole grains—dropped by approximately one point on an 80-point scale. Simultaneously, the proportion of energy derived from "discretionary" foods, such as energy-dense snacks and sugary beverages, rose by about 1%. While these numbers may seem small, scientists warn that even minor shifts toward poorer nutrition during these formative years are associated with higher body mass index and greater fat mass in adulthood.

Variations by Living Arrangement and Social Context

The study found that the specific nature of a young adult's new living arrangement significantly influenced their dietary outcomes. Surprisingly, those who moved in with a romantic partner experienced the largest initial reduction in their DASH diet scores. Those moving in with friends or choosing to live alone also saw declines, though to a slightly lesser extent. Interestingly, moving out to live alone actually resulted in a slight initial decrease in discretionary food intake by 0.65%, whereas moving in with friends or a partner saw that intake spike by 1%. This suggests that social environments play a dual role in both supporting and sabotaging healthy eating habits.