Mixed
Secular trends in the UK indicate that younger birth cohorts (born after the 1980s) develop overweight or obesity at significantly younger ages and with higher probabilities than older cohorts (born before the 1980s).
If you are raising children in a modern high-income environment, expect a higher baseline risk of overweight/obesity compared to previous generations. The data suggests this risk manifests earlier (childhood/adolescence) rather than just in adulthood. Focus on early-life environmental factors (diet, activity) as the primary lever for prevention, as the 'normal' trajectory has shifted.
By age 10 years, the estimated probabilities of overweight or obesity in cohorts born after the 1980s were 2–3 times greater than those born before the 1980s... the age when a 50th centile first entered the overweight range... decreased across NSHD, NCDS, and BCS from 41 to 33 to 30 years in males and 48 to 44 to 41 years in females.
Why this rating
Large longitudinal sample (n=56,632) across 5 cohorts spanning 70 years.
Source
How Has the Age-Related Process of Overweight or Obesity Development Changed over Time? Co-ordinated Analyses of Individual Participant Data from Five United Kingdom Birth Cohorts
William Johnson et al. · PLoS Medicine · 2015
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