Research

Energy balance

Young adults (ages 18-41) experience significant secular trends of weight gain (0.55-0.96 kg/year) and aging-related weight gain (peaking in early to mid-twenties), leading to increased prevalence of overweight and obesity regardless of baseline weight status or education level.

If you are in your 20s or 30s, expect to gain some weight naturally as you age, but be aware that societal factors (sedentary work, food availability) are driving a significant additional weight gain trend. To counteract this, focus on maintaining physical activity levels and monitoring diet, as prevention is easier than reversal in this age group.

GoodSupportsHIGH confidence
Each race-sex group experienced significant secular weight gains, ranging from 0.96 kg/year... in African-American women to 0.55 kg/year... in White women. Significant secular gains were present during each follow-up period. Each race-sex group also experienced significant weight increases related to aging during their early to midtwenties.
Cora E. Lewis et al. · American Journal of Epidemiology · 2000

Why this rating

Large prospective cohort (n=5,115), 10-year follow-up, rigorous statistical modeling separating secular and aging trends.

Source

Weight Gain Continues in the 1990s: 10-year Trends in Weight and Overweight from the CARDIA Study

Cora E. Lewis et al. · American Journal of Epidemiology · 2000

DOI 10.1093/oxfordjournals.aje.a010167

cohort · n=5115Cited 471×
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DOI resolved against Crossref · corpus check 2026-06-10

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