Change in eating pattern as a contributor to energy intake and weight gain during the winter holiday period in obese adults

Abstract

Background/objectives: The winter holiday season in the United States, which spans mid-November to mid-January, contributes to over half of annual body weight gain. Although self-reported data have linked this weight change to both increased energy intake and reduced physical activity, objective techniques have never been used; and thus, the actual cause of holiday weight gain is controversial. Here, we aimed to determine changes in components of energy balance leading to the holiday weight gain.

Methods: Body weight change was compared between the pre-holiday (mid-September to mid-November) and the holiday period (mid-November to early January). Total energy expenditure (TEE) was measured using doubly labeled water during holiday time (early to mid-December). Subjective (ratings) and physiological (appetite-regulating hormones) measures of appetite, eating-away-from-home frequency, and incentive salience of food pictures were also evaluated.

Results: In 23 obese adults (87% female), body weight change during the holidays (0.41 ± 0.42 kg) was significantly higher (P = 0.02) than the body weight change during the pre-holiday period (-0.86 ± 0.42 kg). TEE was unchanged during the two periods, suggesting no role of energy expenditure on weight gain. However, participants reported lower satisfaction after a meal pre-load which was significantly correlated with increased body weight during the holiday period. An increase in number of episodes of eating at sit-down restaurants was also reported during that period. Overall, these changing behaviors were supported by a non-significant increase in energy intake (+80 kcal/day, P = 0.07) observed during the study holiday period.

Conclusion: We conclude that a decrease in energy expenditure does not result in the weight increase, but that increase in food intake is the more likely cause. Our data imply that compromised internal satiety mechanisms in presence of external food cues and diet-related behavioral variables during the holidays may influence weight gain.

Figure 1.. Experimental design

(a) Study protocol for longitudinal study design with 8-week pre-holiday and 8-week holiday period. Anthropometric measures, appetite ratings, blood samples, and questionnaire data, and DLW administered at visit 1 (V1) and visit 4 (V4). On visit 2 (V2) and visit 5 (V5) follow-up urine samples were collected.

Figure 2.. Comparison of probable confounders to energy balance during the holiday period

(a) The Seasonal Pattern Assessment Questionnaire (SPAQ) was used to measure markers of Seasonal Affective Disorder (SAD), rated on a total scale of 0 to 24, with higher numbers indicating SAD. There were no differences in SPAQ scores between the pre-holiday (V1) and the holiday period (V4), indicating no SAD. (b) An average of salivary cortisol samples collected on three consecutive weekdays, were not different between the holiday (the week following V1) and pre-holiday period (the week following V4), indicating no differences in stress levels. *p<0.05. Data are represented as mean ± SEM. A paired t-test was used to make the comparisons.

Figure 3:. Comparison of subjective measures of appetite prior to and in response to a test meal.

Participants rated hunger, fullness, capacity to eat more, and satisfaction on a 10 cm scale. Participants were significantly less satisfied (p = 0.02) with their test meal during the holiday period (V4 vs V1). There were no differences in hunger, fullness, or capacity between the pre-holiday and holiday period. A two-way repeated measure ANOVA was used to make the comparisons.

Figure 4.. Changes in energy balance components and effect of eating-away-from-home frequency on energy intake during the holiday period

(a) The average number of times per week participants reported eating at sit-down restaurants during the pre-holiday period (average of V1, V2, V3) vs the holiday period (average of V4, V5, V6). Eating at sit-down restaurants increased (one-tailed, p = 0.03) during the holiday period. (b) There was a trending positive correlation (p = 0.05) between eating at sit-down restaurants and energy intake over the pre-holiday and the holiday periods. Pearson’s correlation was used for this analysis. (c) The changes in energy intake and expenditure as measured by collection of doubly labeled water (DLW) during the pre-holiday (V1) and holiday periods (V4). The total energy expenditure did not differ between two periods, while energy intake increased. Data are represented as mean ± SEM. A paired t-test was used to make the comparison.