LIFESTYLE BEHAVIOURS AND RISK OF EARLY-ONSET NON-COMMUNICABLE DISEASES AMONG YOUNG ADULTS: A NARRATIVE REVIEW

Abstract

Background: Non-communicable diseases (NCDs) are the leading cause of global morbidity and mortality, with an increasing trend of early onset among young adults. This shift is largely driven by modifiable lifestyle behaviours such as obesity, physical inactivity, unhealthy dietary habits, inadequate sleep, and substance use. The growing prevalence of these risk factors, particularly in developing countries like India, poses a significant public health challenge. Objective: This narrative review aims to examine the association between lifestyle behaviours and the risk of early-onset NCDs among young adults, and to identify key determinants and preventive strategies aligned with global priorities. Methodology: A narrative review was conducted using literature from PubMed, Google Scholar, Scopus, and Web of Science, along with reports from national and international organizations such as the World Health Organization. Studies published between 2010 and 2025 were included. Relevant articles were screened based on predefined inclusion and exclusion criteria, and findings were synthesized into thematic domains including obesity, physical inactivity, dietary patterns, sleep behaviour, and substance use. Results: The review found that overweight and obesity affect approximately 20–30% of young adults in India, while 30%–40% exhibit physical inactivity. Unhealthy dietary patterns were observed in more than 50% of individuals, with low consumption of fruits and vegetables. Inadequate sleep (<7 hours) was reported in 30%–40% of young adults, contributing to metabolic disturbances. Substance use, including tobacco (20%–25%) and alcohol (15%–20%), further increased NCD risk. These factors were associated with a 1.5 to 3 times higher risk of developing early-onset diabetes, hypertension, and cardiovascular diseases, particularly when multiple risk factors coexisted. Conclusion: Lifestyle behaviours play a crucial role in the development of early-onset NCDs among young adults. The clustering of modifiable risk factors significantly increases disease burden, highlighting the need for early preventive interventions. Strengthening health promotion strategies, behavioural change communication, and policy-level interventions is essential to reduce the long-term impact of NCDs.