"Most of us gain 2lb over Christmas and never lose it," is the uncheerful news on the Mail Online website. It reports on a study that found that volunteers gained around 0.8kg between November and January that they then struggled to lose…
"Most of us gain 2lb over Christmas and never lose it," is the uncheerful news on the Mail Online website. It reports on a study that found that volunteers gained around 0.8kg between November and January that they then struggled to lose.
In this small study, researchers assessed 148 people around the time of Thanksgiving in the US (the last Thursday in November) and again in early January. They found there were significant increases in body weight and fat, body mass index, blood pressure and resting heart rate.
Significantly, they found no differences between people who exercised at the recommended levels and those who didn't. They also found that someone's initial weight could be used to predict whether or not their weight or body fat percentage increased.
However, the researchers didn't do further long-term assessments, so we can't say if these increases were sustained. It is possible that the small increase in weight was lost in the New Year.
As people reported their own physical activity levels, this may not have accurately reflected how much exercise they did – many of us tend to overestimate the amount of exercise we do.
If you are concerned about not being able to lose the weight you gain over Christmas, not gaining the weight in the first place could be your best bet. Read more about how to Avoid winter weight gain.
The study was carried out by researchers from Texas Tech University in the US. Sources of funding were not reported. It was published online in May 2013 in the peer-reviewed European Journal of Clinical Nutrition.
The headline on Mail Online is not supported by the findings of this study. Because the study did not perform ongoing assessments, it is not possible to say if the small increases in weight gain ended up "spending a lifetime on the hips", as it reports.
Headlines aside, the reporting of the study was accurate and contained some useful advice from one of the lead researchers.
This was a small observational study looking at whether or not body changes occurred in a group of Americans over the "holiday period".
An observational study is when researchers simply observe groups of people without changing their exposures or circumstances.
The study included and analysed 48 men and 100 women aged 18 to 65 who were recruited using flyers, by word of mouth and electronic announcements at a university in the US.
Researchers carried out initial assessments on participants in mid-November (around 10 to 14 days before Thanksgiving in the US) and repeated the assessments in early January. The average time between assessments was 57 days.
Assessments were carried out for:
Height and weight measurements allowed the researchers to calculate body mass index (BMI), which is used to measure if a person's weight is healthy (a BMI between 18.5 and 24.9 is considered in the healthy range).
The researchers used the second physical activity assessments carried out in mid-January to group participants as either:
The researchers then used statistical techniques to compare the results of the November and January assessments to see if there were any changes during this "holiday period".
The study authors report the participants were "blinded" to the purposes of the study and were told that the study was about short-term changes in health. This was done to prevent the participants from altering their eating or physical activity patterns because of their involvement in the study.
Of the 148 participants, 78 reported that they met the US guidelines for physical activity (at least 150 minutes of moderate-intensity exercise per week), and 71 reported exercising for less than this and were considered "non-exercisers".
The main findings of the study were:
There were no statistically significant differences for men and women for any of the assessed outcomes, and there were no significant differences between "exercisers" and "non-exercisers" for changes in body weight, body fat percentage or body mass index.
Participants who were considered obese at the first assessment had significantly greater increases in body fat percentage than participants with a healthy weight. Initial body weight (but not initial body fat percentage, age, gender or exercise) was a predictor of changes in body weight and body fat percentage.
The researchers conclude that significant increases in body weight, body fat percentage, blood pressure and heart rate were seen in healthy adults during the "holiday season". They report participants gained 0.78kg on average, which indicates the majority of average annual weight gain – reported by other researchers to be about 1kg per year – may occur during the "holiday season".
They say the likelihood of gaining more body fat increases as the extent of how overweight a person is increases, and that initial body weight was a factor that predicted gain in body weight and body fat percentage.
The researchers said it was possible that the total energy intake exceeded any potential benefits of daily physical activity.
Overall, this study provides limited evidence of so-called "weight creep" during the "holiday period".
There were only a relatively small number of people (148) included in the study who were all from one area in the US, so the findings may not be generalisable to other groups.
The study has some other limitations, some of which were noted by the researchers:
This study does not provide evidence that "most people gain 2lb over Christmas and never lose it", as the Mail Online reports.
It also does not change the recommended physical activity guidelines in the UK, which are at least 150 minutes of moderate-intensity physical activity per week.
If you are concerned about gaining weight over Christmas, there are steps you can take without ruining your fun.
Read more about Avoiding winter weight gain and Exercising in winter.