Does diet strictness level during weekends and holiday periods influence 1-year follow-up weight loss maintenance? Evidence from the Portuguese Weight Control Registry

There is not much evidence about how diet strictness during weekends and holidays influence long-term weight loss maintenance. Our aim was to examine how dieting more or less strictly during weekends and holidays (vs. weekdays and non-holiday periods) influence weight loss maintenance. Participants (n = 108) from the Portuguese Weight Control Registry indicated whether they had a more or less strict diet regimen during weekends compared to weekdays. A similar question about holiday and non-holiday period’ diet regimen was answered. Weight and height were measured at baseline and 1y follow-up. A 3% maximum weight variation defined participants as “non-regainers”. General level on dieting strictness on weekends vs. weekdays (r = − 0.28, p < 0.01) and holidays vs. non-holidays (r = − 0.33, p < 0.001) predicted 1y weight change. Participants who reported being less strict on weekends (OR = 0.34, 95% CI: 0.15–0.81) were more likely to be non-regainers when compared with the ones who reported being more strict on weekends. Non-significant results were found during holidays (OR = 0.47, 95% CI: 0.20–1.09). Adopting a less strict diet regimen during weekends, when compared to weekdays, was a behavioral strategy associated with long-term weight management in our sample.