Effect of the Holiday Season on Weight Gain: A Narrative Review

Table 1

Studies evaluating the effect of the holiday period on body weight in adults.

Author, year, and country	Number of participants, age, sex, BMI, and prevalence of overweight/obesity	Date of	Sample, masking of participants,	Mean weight change; ± SD	p value
Rees et al.; 1985; United Kingdom	22 healthy adults and 13 adults with T2DM; (age, sex, BMI, and prevalence not reported)	Measurements: December 10, 22 and 29. January 5 and 26.	Convenience sample.; No.; Retention 76%.	Healthy =  kg; T2DM =  kg
Reid and Hackett; 1999; United Kingdom	26 adults; 17–59 years; Men = 42%; Women = 58%; BMI =  kg/m^2; Low weight = 23%; Normal weight = 65%; Overweight = 12%	Initial measurement: December 18 to 21.; Final measurement: January 4.	Convenience sample.; No.; Retention 96%.	kg
Yanovski et al.; 2000; United States	195 adults; 19–82 years; Men = 49%; Women = 51%; BMI  kg/m^2; Normal weight = 52%; Overweight = 27%; Obese = 21%	Initial measurement: in mid-November.; Final measurement: in early January.	Convenience sample.; Yes.; Retention 98%.	kg
Wagner et al.; 2012; United States	34 adults; 23–61 years; Men = 41%; Women = 59%; BMI =  kg/m^2; Normal weight = 65%; Overweight = 35%	Initial measurement: November 24-25.; Final measurement: January 5-6.	Convenience sample.; No.; Retention 92%.	kg
Cook et al.; 2012; United States	443 adults; 40–69 years; Men = 55%; Women = 45%; BMI man =  kg/m^2; BMI woman =  kg/m^2; Normal weight = 30%; Overweight = 42%; Obese = 28%	Initial measurement: mid-September–mid-October.; Final measurement: mid-January–early March.	Convenience sample.; Yes. Secondary analysis.; Retention 98%.	Man =  kg; Woman =  kg
Stevenson et al.; 2013; United States	148 adults; 18–65 years; Men = 32%; Women = 68%; BMI =  kg/m^2; Normal weight = 57%; Overweight = 26%; Obese = 17%	Initial measurement: mid-November.; Final measurement: mid-January.	Convenience sample.; Yes.; Retention 70%.	kg

Weight of participants in all studies was measured as part of the study. Masking: the participants did not know that the study objective was to evaluate the effect of holidays on obesity parameters. The winter holiday season period was not specifically measured; however, the evaluation covered the month of December; BMI: body mass index. T2DM: type 2 diabetes mellitus.