Weight Gain Over 6 Years in Young Adults: The Study of Novel Approaches to Weight Gain Prevention Randomized Trial

Objective: The study objective was to determine whether two self-regulation interventions that reduced 3-year weight gain in young adults remain effective at 6 years.

Methods: A randomized trial was conducted in two academic settings in 599 young adults, aged 18 to 35 years, with normal weight or overweight; 504 (84%) reconsented for a 6-year extension (Study of Novel Approaches to Weight Gain Prevention-Extended [SNAP-E]) with ongoing intervention and assessments. Weight gain over 6 years was compared for all assigned to Control, Large Changes (LC; lose 5-10 pounds initially), and Small Changes (SC; make small daily changes in intake and activity).

Results: Weight change from baseline to 6 years did not differ significantly among the three groups (Control = 3.9 kg, SC = 4.1 kg, and LC = 2.8 kg). However, there was a significant age-by-treatment interaction (P = 0.002). Among those < 25 years old, weight gain from baseline to 6 years averaged 7.3 kg in the Control group and was reduced by almost 50% in LC and SC. LC also significantly reduced mean weight gain (area under the curve) over 6 years compared with Control or SC.

Conclusions: Although the interventions did not reduce weight gain at 6 years for the full cohort, they were effective in those < 25 years old. Future efforts should focus on young adults aged 18 to 24.9 and test more intensive interventions with more diverse participants.