Liking for and valence of sugar-and-fat mixtures are heightened in weight-reduced individuals relative to individuals not weight-reduced.

Weight-reduced individuals rated sugar-sweetened mixtures with higher liking than non-weight-reduced individuals.

• WR participants were 22.9 lbs ± 9.3 lbs below self-reported maximum lifetime body weight; NR participants were 1.3 lbs ± 4.3 lbs of self-reported maximum lifetime body weight.
• Participants rated 12 mixtures varying in milkfat (0, 3.3, 11, 38%) and added sugar (0, 10, 20%).
• Groups consisted of N = 10M, 10F per group (ages 18–67).
• Groups were matched across body weight, body fat, BMI, fat-free mass, muscle mass, visceral fat, and resting metabolic rate.

The WR group rated sugar-sweetened mixtures positively and unsweetened mixtures negatively, while the NR group provided largely neutral ratings across all mixtures.

• This pattern indicates a qualitative difference in hedonic valence between groups, not just magnitude.
• NR participants showed near-neutral liking ratings across the full range of sugar and fat concentrations tested.
• WR participants showed a clear positive-to-negative gradient depending on sugar content.

In the NR group, reward sensitivity negatively correlated with liking for unsweetened mixtures and positively correlated with liking for sugar-sweetened mixtures.

• Reward sensitivity was measured using the Sensitivity to Punishment and Sensitivity to Reward Questionnaire (SPSRQ).
• Higher reward sensitivity in NR individuals was associated with greater liking for sugar-sweetened mixtures and lower liking for unsweetened mixtures.
• This relationship followed an expected pattern linking general reward sensitivity to hedonic taste responses in non-weight-reduced individuals.

The relationship between reward sensitivity and liking for food mixtures was absent in the WR group, indicating a decoupling of general reward sensitivity from hedonic taste responses in the weight-reduced state.

• This decoupling was observed independent of body composition, as groups were matched on body weight, body fat, BMI, fat-free mass, muscle mass, visceral fat, and resting metabolic rate.
• The authors describe this as 'a decoupling of general reward sensitivity from hedonic taste responses in the weight-reduced state independent of body composition.'
• The absence of the reward sensitivity–liking correlation in WR individuals suggests a state-dependent alteration in hedonic processing.

Heightened sugar liking and its decoupling from trait reward sensitivity in weight-reduced individuals may represent biological mechanisms defending against sustained weight loss.

• The authors hypothesize these findings represent 'mechanisms by which biological systems defend against sustained weight loss and contribute to the challenges of long-term weight loss maintenance.'
• Physiological adaptations to weight reduction are well-established; this study extends that framework to hedonic responsiveness to food.
• The study tested the hypothesis that body weight reduction results in increased liking for sugar-and-fat mixtures.