Development and Validation of the Psychometric Properties of the FitMIND Foundation Sweets Addiction Scale—A Pilot Study

Background: The rising consumption of ultra-processed foods, especially those high in added sugars, poses a growing public health concern. Although several tools exist to assess food addiction, there is a lack of validated instruments specifically designed to measure addiction-like behaviors related to sweet food intake. Objectives: This study evaluates the psychometric properties of the FitMIND Foundation Sweets Addiction Scale (FFSAS), adapted from the Yale Food Addiction Scale 2.0 (YFAS 2.0), using data from Polish adults recruited through the FitMIND Foundation. Methods: The FFSAS was evaluated by 11 expert judges on four criteria: clarity, content validity, linguistic appropriateness, and construct representativeness. Afterwards, 344 adult volunteers (mean age 40.6 ± 10.7 years, 78% female, mean body mass index (BMI) 27.86 kg/m²) completed online FFSAS and provided demographic data, BMI, and self-reported sweets consumption. Internal consistency was assessed with Cronbach’s alpha, external validity was examined through Spearman’s correlations. Moreover, we conducted the Exploratory and confirmatory factor analyses (EFA and CFA). Results: Reliability of the FFSAS was confirmed by the expert validation. The scale demonstrated the good overall internal consistency (α = 0.85), with subscales like Tolerance (α = 0.916) and Withdrawal (α = 0.914) showing particularly high reliability. The FFSAS scale was moderately correlated with sweets consumption frequency (ρ = 0.39, p < 0.05) and guilt (ρ = 0.35, p < 0.05). Exploratory factor analysis (EFA) revealed a robust three-factor structure, explaining 68.6% of the variance, with excellent internal consistency (Cronbach’s α = 0.951–0.962) and high sampling adequacy (KMO = 0.956). Confirmatory factor analysis (CFA) indicated suboptimal model fit (CFI = 0.74, TLI = 0.69, RMSEA = 0.14), with significant chi-square (χ² = 3761.76, p < 0.001). Conclusions: This pilot study demonstrated that the FFSAS may be a valid tool for assessing the sweet food addiction in adults. . Future research should focus on assessing the FFSAS suitability on more diverse populations of other countries, for further validation.