Terrified that a little weekend indulgence my ruin your hard work during the week? Fear no more! New research led by the VTT Technical Research Center in Finland shows a weekly rhythm in people’s weight fluctuation over the seven days of the week. 

Published in Obesity Facts, researchers examined the weight of 80 adults –aged 25 years old to 62 years old – each day after waking up for a minimum of 15 days. There were three groups of participants in the study:

• Individuals who lost at least 3 percent of their body weight
• Individuals who gained on a least 1 percent
• Individuals who maintained their weight between those minimums

They found an overall pattern of increased weight on Sundays and Mondays with all three groups. Individuals who lost weight recorded their lowest weight on Friday. The researchers believe that the individuals managed to compensate the weekend weight gain during the work week.

More research needs to be done due to the relative small subject pool size. The data collected was also all self-reported. The study participants could have made a mistake or purposefully altered their recorded weights.

This purpose of this study was to show how long-term habits make more of a difference than short-term mistakes. A flexible eating pattern – allowing yourself to eat a slice of cake – can help you sustain eating healthy eating habits in the long run.

"Some indulging during weekends makes no harm but for successful weight loss it is important to notice these rhythms and take steps to reverse the upward trends," said Cornell University behavioral economist Brian Wansink, one of the study authors.

Cornell University and Tampere University of Technology collaborated with VTT Technical Research Centre of Finland for this study.

Additional Resource:

Weight Rhythms: Weight Increases during Weekends and Decreases during Weekdays