A prospective study on vacation weight gain in adults

Highlights

• Short-term vacations result in significant and persistent weight gain.

• A trend for greater physical activity during vacations does not prevent weight gain.

• Perceived stress and systolic blood pressure decrease after a 1–3 week vacation.

Abstract

Purpose

To determine if a 1- to 3-week vacation in adults leads to weight gain and whether that gain persists 6 weeks later.

Methods

122 adults going on a 1- to 3-week vacation completed 3 visits. The visits were 1 week prior to, 1 week post, and 6 week post vacation. Height, weight, blood pressure, and waist-to-hip ratio, physical activity (International Physical Activity Questionnaire — IPAQ) and stress (Perceived Stress Scale — PSS) were measured.

Results

Body weight increased on vacation (0.32 ± 0.08 kg, p < 0.05) and this increase persisted so that total weight gain was 0.41 ± 0.11 kg (p < 0.05). No difference in weight gain based on BMI was found (0.28 ± 0.13 kg, 0.39 ± 0.14 kg, and 0.48 ± 0.27 kg for normal weight, overweight, and obese, respectively). PSS decreased for the study (17.1 ± 0.5 to 14.9 ± 0.6 for pre-vacation to 6-weeks post-vacation, respectively; p < 0.001), and total physical activity tended to increase on vacation (3940 ± 235 vs. 4313 ± 344METs, for pre- vs. post-vacation, respectively; p = 0.10) and decreased in the post-vacation period (4313 ± 344 vs. 3715 ± 306METs, p < 0.05).

Conclusions

Vacations resulted in significant weight gain (0.32 kg), and this weight gain persisted at the 6-week follow-up period. The weight gain appeared to be driven by increased energy intake above energy requirements. This gain could be a significant contributor to yearly weight gain in adults and therefore affect obesity prevalence.

Introduction

Although the rise in obesity prevalence has slowed in the past few years and remains stable, nearly 70% of the United States adult population is classified as overweight or obese [1], [2], [3]. Longitudinal studies among U.S. adults show that average weight gain is somewhere between 0.4 and 1.0 kg (0.9 and 2.2 lbs) per year [4], [5]. Accumulation of this small, yet consistent, weight gain, which appears to begin with early adulthood, can lead to substantial weight gain over a long period of time (15–30 years) and contribute greatly to obesity. However, it does not appear that adults are in a slight energy surplus every day of the year. Rather, the evidence shows that very short periods of time throughout the year can contribute a significant portion of the average yearly weight gain.

The most commonly studied time periods that are thought to contribute to yearly weight gain are the holiday season as well as summer vacations in children and adolescents. Our research lab, and others, have shown that the holiday season (mid-November to early January) can result in weight gain and fat mass gain in adults, and that overweight/obese individuals are at risk for gaining the most [5], [6], [7], [8], [9]. Further, it has been shown that this weight gain persists and likely contributes toward yearly weight gain [10]. Summer vacations (2–3 months long), while children and adolescents are not in school, has also been a time period of intense focus [11], [12], [13]. Accelerated summer weight gain has been reported in most studies, with the greatest weight gain occurring in overweight children and adolescents [11].

Interestingly, to date, no one has examined the effects of a short-term vacation (ranging from 1–3 weeks) on weight gain, or its possible contribution toward yearly weight gain, in adults. The lay press reports enormous weight gains on vacations [14]; yet, there is no data to back up these claims. The purpose of this study was to determine if a 1–3 week vacation in adults would alter body weight and if those weight changes would persist 6 weeks post-vacation. We also wanted to see if stress and physical activity levels changed during vacation. We hypothesized that vacations would lead to increases in body weight that would also persist 6-weeks post-vacation. We also hypothesized that stress levels would be higher pre-vacation and that physical activity levels would decrease during vacation.