Putting on the Holiday Pounds

It seems that lately I’ve been focused on articles about people getting fat or with their obsession with losing weight. Considering that today is Thanksgiving, that wonderful American holiday where it is socially acceptable to eat yourself into oblivion, I figure the topic is appropriate. Of course, I could just be using this as a proxy for going to the gym – you know, reading about other people getting fat instead of stepping on my scale. Apparently stepping on and off a soapbox is not aerobically effective. Maybe I should have written about the article called “Chocolate and Prevention of Cardiovascular Disease: A Systematic Review” instead to justify my chocolate habit. Ah well.

Today’s post is actually on two studies, both about gaining weight during the holidays. The fact that Americans are overweight and obese isn’t exactly a secret. Obesity has increased in this country by over 50 percent over the past couple of decades. It affects all ages, socioeconomic classes, and ethnicities. Obesity is serious business both as a health risk as well as impacting healthcare costs. Therefore, both having an understanding of the times when people are more likely to gain weight and the development of effective strategies for prevention are important. For most adults, there is a slight increase in weight gain over time. We’re talking about 1.5 pounds (0.2 to 0.8 kg) per year. However, certain times of the year can affect body weight through changes in food intake, mood, and physical activity. Sound familiar? It’s like part of the definition of the holiday season. Self-report based studies show that Americans will gain about 5 pounds during this time of year. Is that accurate? Maybe. I chose these two studies in particular because they are on the same topic, are data based rather than self-report based, and because they look at two different segments of the population. The first is on average adults and the second on college students. Both studies looked at the “holiday season” which is considered to start with Thanksgiving (the third Thursday of November) through New Years Day.

The first article is from the New England Journal of Medicine. A total of 195 subjects of good health from ages 19 to 82 were recruited, about half of which were women. These people were seen on four occasions at intervals of six to eight weeks – late September/early October, just before Thanksgiving, after New Years Day, and about mid-year. During each visit height, weight, and vitals (like temperature and blood pressure) were measured and a questionnaire filled out that evaluated factors such as stress, dietary and activity patterns, and depression. The study found that in contrast to the common perception of weight gain during the holiday season, a vast majority of their subjects’ weight changed very little, only about a pound (0.48 kg). When asked, the participants believed that they had gained up to four times as much weight as they actually did. The study subjects that gained the most weight, over 5 pounds (2.3 kg) were those who were more likely to be overweight or obese. The holiday seems to be extra problematic for this group.  The down side? The weight that people put on during the holiday season was maintained during the postholiday season. Add the weight gained over the holiday season (which isn’t lost) to the weight gained over the rest of the year and you have a potentially problematic long term weight gain situation.

The second study looked at college students, a convenient and willing demographic (free money and food are a good driver for participation) as well as a group with a high risk for obesity development. This demographic traditionally has bad or changing nutritional and physical habits (just read the Beware the Freshman 15? post from last month). The researchers looked at 82 male and female students ranging in age from 18-40 years (mean of 23 years), freshman to graduate students.  As with the first study, they collected height, weight data, and DXA data (Duel Energy X-ray Absorptiometry which assesses percent body fat, fat mass, and fat free mass) at 3 time points: A week prior to Thanksgiving, just after Thanksgiving, and after New Years Day. As with the previous study, this one showed no significant increase in the body weight of its participants. However, they did find total fat mass and percent body fat to increase for the entire holiday season. Weight gain was specifically related to Thanksgiving with an increase of about 1 pound (0.5 kg). The good news, and different from the other study, was that a change in body weight and fat free mass was found which indicates that at least some of the weight increase may be due to increasing muscle mass. Additionally, when the subjects returned for follow-up they had returned to their pre-holiday weight values, although not necessarily the previous body fat percentage. Perhaps because they were attempting to return to a “preset weight.” It would be interesting if they had attempted to correlate this preset weight idea to a New Years' resolution, but perhaps that is another paper.

The overall idea of both paper? You’re probably gonna gain weight this holiday season, but perhaps not as much as you think. It’s also probably a good idea to work on losing it afterwards. So eat big now but remember to eat well and exercise later.

Gobble, gobble. Oink, oink.

Article 1:
Yanovski, Jack A. et al. (2000) A prospective study of holiday weight gain. New England Journal of Medicine: 342(12), 861-867. (PMID: 10727591)

Article 2:
Hull, Holly R., Casey N. Hester, and David A. Fields (2006) The effect of the holiday season on body weight and composition in college students. Nutrition & Metabolism:   3, 44-47 (DOI: 10.1186/1743-7075-3-44)