The Myth of the Freshman 15

StudentsIts nearly back-to-school time. For many recent high-school graduates, the next week or two represent the beginning of a whole new chapter: post-secondary education. Of all the challenges college freshmen need to contend with, worrying about potential weight gain should be the least of their worries. Unfortunately, due to a pervasive myth that has been too often repeated, weight gain may be on the minds of many undergraduate students.

It is a commonly held assertion that the average freshman will gain approximately 15lbs during the 2 semesters of 1st year university or college.

However, my experience and the results of numerous studies suggest that the phenomenon is purely myth, and a student who gains 15 lbs during their 1st year is clearly an exception rather than the rule.

The average university school year is approximately 30 weeks. Thus, to gain 15lbs over the 30 weeks of 2 semesters would require an additional 1750kcals per week – which is almost an extra days worth of calories added every week. That is impressive chronic overeating.

During my first year of university, I definitely did not experience a substantial increase in body weight. If anything, the initial stress of being away from home, the foreign environment, the increased academic workload, being forced to eat cafeteria food instead of my mother’s delicious cooking actually caused me to drop a few pounds. By second semester I was well adjusted, had figured out the ‘healthier’ eating options on campus, and had re-acquainted myself with regular exercise. When I went home for the summer, I had actually arrived in better shape (and approximately 5 pounds lighter) than when I first departed.

But that’s just my isolated experience.

What does the research suggest?

Back in 2006 Morrow and colleagues published a study in the journal Obesity investigating the notion of a freshman 15. This study has one of the largest samples to look at the phenomenon of freshman weight gain, and is the only one (to my knowledge) to assess body composition. In that study, 137 female freshmen at the University of Oklahoma were assessed for body weight and composition at the start of the school year and again at the end of the spring semester.

While the study did find a statistically significant increase in body weight from the start to the end of 1st year, the average weight gain was approximately 2lbs – a far cry from the commonly touted gain of 15 lbs. And of those 2 lbs, about 25% was due to an increase in muscle.

What’s also obvious when examining the results of this study is that about a quarter of the students actually lost weight during the 1st year, and many maintained their baseline weight.

So while I may be in the minority of those who lose weight in 1st year, it appears to be an experience shared by a quarter of first year students.

More importantly, the freshman 15 is more accurately the freshman 2 – but that doesn’t sound nearly as exciting or catchy.

Regardless of the magnitude of weight change, the transition from home to living on your own is a critical period for developing your own dietary and activity patterns, and thus educating 1st year students on proper nutrition and regular exercise is of utmost importance.

Given the appropriate education, first year students can not only resist weight-gain, they can actually improve on the lifestyle habits they had adopted from their parents over the past 17-18 years.

That is, if your parents didn’t have the best lifestyle habits, moving away from home may be an excellent chance to fix the dietary and physical activity patterns that were handed down to you from your folks.

Of course, I knew students who adopted a regular diet of beer, pizza, burgers and video games during university – these individuals fared less well with their weight and health . But this is far from the norm as often popularized by the freshmen 15 myth.

Debunking the myth that all freshmen gain weight may help remove the excuse to eat unhealthy and become sedentary – we often allow suggestion to affect our behaviour more than we’d like to think. If it is expected that most students will gain an average of 15lbs, the incoming students may feel that how their body will look in 8 months it is out of their control.

So to all incoming first-year students: Don’t buy into the hype and fear-mongering. You are more likely to be a freshman 0 than a freshman 15.


Category: nutrition, Obesity Research, Peer Reviewed Research, Physical Activity | Leave a comment

Drinking water before meals leads to weight loss

waterOver the years, we’ve often recommended the simplest of behaviour changes to improve your health: drinking more water during the day. There’s certainly no downside to staying hydrated, plus the increased trips to the bathroom will ensure you get up from your desk a few more times every day. I probably don’t have to convince you any more of the dangers of sitting for prolonged periods – Travis has done a fine job of that. But what if there was more behind the advice to drink more water? What if something as simple as a few more glasses of water resulted in weight loss?

A new study, published in the September issue of the journal Obesity suggests water can be an effective tool to combat excess weight, albeit modestly.

In the study, Parretti and colleagues randomized 84 adults with obesity to one of two basic conditions: 1) drinking 500 ml of water 30 min before their main meals or 2) a control group where participants were supposed to visualize being full before having their meals.

At the start of the study, all participants were given a 30 minute face-to-face weight management consultation and a 10 minute follow-up telephone consultation at 2 weeks.

41 participants were randomized to the intervention group and 43 to the control group, and their weight was tracked until the 12 week conclusion of the study.

And what effect could something as subtle as drinking water before meals have on one’s body weight?

At 12-weeks, participants who “preloaded” with water reduced their body weight by 1.3 kg more than participants in the control group.

Just to be sure, the authors performed another analysis where they adjusted for potential differences in the two study groups, such as ethnicity , age, and gender; this analysis confirmed significantly greater weight loss at 12 weeks among those who drank water before their meals..

Is this surprising?

Well, you may recall a somewhat similar prior study we discussed on this blog back in 2009 that randomized overweight/obese older men and women to either a hypocaloric diet alone or a hypocaloric diet plus increased water consumption for a duration of 12 weeks.

The hypocaloric diet consisted of 1200 calories for the women and 1500 calories for the men. Those in the diet + increased water group were required to consume 500 ml of water (2 cups) 30 minutes prior to each of the 3 large daily meals (breakfast, lunch, dinner).

While participants in both groups lost a significant amount of weight (5-8kg) in response to the diet, those who also consumed more water before their meals lost an additional 2 kg in comparison to the diet only group.

The greater weight loss in the group consuming pre-meal water could be the result of smaller caloric intake during each meal (~40 calories less per meal), as shown during the baseline laboratory test meals.

The findings of these randomized controlled studies are in agreement with prior epidemiological studies showing that caloric intake in water drinkers is on average 200 calories less than among non water drinkers.

The results provide compelling evidence to encourage all those attempting to lose weight to increase their daily intake of water to help in their efforts. Specifically, one should consume approximately 2 cups of water, about half an hour prior to most meals.


Reference: Parretti et al. 2015. Efficacy of water preloading before main meals as a strategy for weight loss in primary care patients with obesity: RCT. 2015; 23(9): 1785-1791.

Category: News, nutrition, Obesity Research, Peer Reviewed Research | 1 Comment

Big Food and Public Health Research

This post has been updated adapted from a post in 2012, in response to the controversy over the Global Energy Balance Network.

As an obesity researcher I have publicly grappled with the ethics of working with the food industry here on Obesity Panacea for several years.  Originally I had always leaned more towards the view of engaging with industry.  While I felt that people like Michele Simon and Yoni Freedhoff made good arguments against engaging with Big Food, I felt it was possible that the positive aspects of engagement (primarily in the form of money for research or other programs that might not be possible otherwise) outweighed their potential to do harm.

However, over the past few years I’ve gradually been pulled toward the views held by Yoni and Michele for 2 reasons:

  1. Big Food seems willing to say or do just about anything to promote their own interests.
  2. Funding public health projects (including research) probably helps Big Food avoid meaningful regulation.

Big Food seems willing to say or do just about anything to promote their own interests.

Take this interview with Coca Cola President for North America Katie Bayne, which has been critiqued by Marion Nestle and Yoni Freedhoff previously.

In the interview, Ms Bayne claims that there is no such thing as an empty calorie:

A calorie is a calorie. What our drinks offer is hydration. That’s essential to the human body. We offer great taste and benefits whether it’s an uplift or carbohydrates or energy. We don’t believe in empty calories. We believe in hydration.

She weighs in on the evidence linking sugar sweetened beverages and obesity (emphasis mine):

There is no scientific evidence that connects sugary beverages to obesity. If you look at the data, you can see that during the same period obesity was rising, sugar intake from beverages was decreasing. Between 1999 and 2010, sugars from soda consumption decreased by 39%, but the percentage of obese children increased by 7%, and 13% for adults.

Note that she didn’t say that the research isn’t air-tight, or that some questions remain, which would be true.  She said there is “no scientific evidence”, which can be easily disproved by heading back to my previous post which surveyed the rather large body of evidence on this exact topic.

She goes on:

Q: Shouldn’t teens drink less cola and more milk and water?

A: Teens should get a healthy diet through food and beverage choices throughout the day.

Q: How much Coke should a kid drink a day?

A: We don’t make recommendations on what kids should drink. But a 12-ounce can of Coke has 140 calories, the same as a lunch-box-size bag of pretzels.

Finally, here is her son’s post-workout hydration regimen:

 If my son has lacrosse practice for three hours, we go straight to McDonald’s and buy a 32-ounce Powerade.

Now if Big Food executives were able to respond to these sorts of questions as a reasonable, rational person, then I would continue to agree that partnerships with industry are the way to go.  But it’s tough to maintain that view after seeing the above interview and others like it, that suggest to me that the food industry has no goal other than profit.  I don’t think that any reasonable person could honestly say that there is no such thing as an empty calorie (especially in the context of obesity), or duck a simple question asking whether it’s healthier for kids to drink more water and less soda. 

Funding public health projects (including research) probably helps Big Food avoid meaningful regulation

My other big problem is with an issue related to corporate social responsibility campaigns. In short, a primary goal of these campaigns is to prevent regulation.  That really worries me.  There are certain areas (e.g. a restrictions on advertising to children, a tax on sugar sweetened beverages, etc) where I feel that regulation is absolutely warranted. So while individual Big Food-funded projects may be fantastic, I worry that it will allow the industry to avoid regulation that could have more far-reaching benefits.  Sort of a win the battle, lose the war situation.

If all public health advocates were to stop partnering with Big Food, this would create a pretty large vacuum in terms of funding (unfortunately, those corporate social responsibility campaigns fund a lot of worthwhile projects… which, as I’ve written previously, is the whole point).  This has always been a big concern for me, and I still don’t know how that vaccuum could be filled (this is far from inconsequential – if we had another way to fill that vacuum, there would be far less need to partner with Big Food in the first place).  This is not an abstract concern – I have not personally received funding from the food industry, although I have worked with several individuals and organizations that have, and have therefore indirectly benefited from these partnerships myself.  However, if the goal is to improve public health, then I’m starting to think that the ends may not justify the means.


Category: News | 4 Comments

What caused the childhood obesity epidemic?

This post was originally published in 2013.  Earlier this week the Global Energy Balance Network made news, and in doing so claimed that there is “virtually no compelling evidence that [fast food and sugary drinks], in fact, is the cause” of obesity.  I am reposting the below article, which summarizes my interpretation of the evidence on the likely causes of the childhood obesity epidemic in developed countries.  Needless to say, I concluded that sugar sweetened beverages are, in fact, a likely contributor to the childhood obesity epidemic.

Earlier this year I was asked to give a talk on the childhood obesity epidemic for faculty and staff of the Faculty of Health Sciences at the University of Ontario Institute of Technology (UOIT). The folks at UOIT were good enough to record the lecture, so I’ve embedded it below (email subscribers can view the video on the blog).

I should note that the video has been edited slightly to remove several “Think-Pair-Share” discussions with the folks attending the lecture. So if I appear to make some random segues from time to time, that’s why.


For a risk factor to be considered a “cause” of the childhood obesity epidemic, two conditions need to be met:

1. The factor must be shown to promote excess weight gain in childhood

2. The factor must have increased before/during the childhood obesity epidemic

Based on those criteria, there are 4 factors that we can say (or at least I say) have contributed to the childhood obesity epidemic with relative certainty. These are:

  1. Sugar sweetened beverages (e.g. pop)
  2. Sedentary behaviour (especially screentime)
  3. Lack of sleep
  4. Adult obesity

People might be surprised that diet and physical activity aren’t on that list. But really, it comes down to measurement issues. It is certainly plausible that diet and physical activity contribute to increased childhood obesity rates. The problem is that the historical data for both of these variables is really weak, and often contradictory. The data for sugar sweetened beverages and screen time isn’t of much better quality, but the findings for both of those outcomes is much more consistent than for physical activity or diet more generally.

In the lecture and paper I also look at a variety of other risk factors (changes in gut bacteria, reduced breast-feeding, etc), and while there are some interesting findings there, it just isn’t to the point where you can make a strong conclusion with respect to obesity rates at the population level.

Check out the video, look at our previous series on the childhood obesity epidemic, or download the review paper that started all of this (it’s an open access paper, and can be downloaded or viewed online for free). Also, my sincere thanks to Drs Ellen Vogel and Meghann Lloyd for inviting me to speak at UOIT – I had a great time, and enjoyed the opportunity to see their new campus.


Category: News | 10 Comments

Coca Cola and Energy Balance

Earlier this week friend and fellow science-blogger Matt Herod sent me a link to a New York Times article outlining a Coca Cola-funded group called the Global Energy Balance Network (GEBN).  It’s a good article, so head over to read it in full.  But the gist of it is summed up by the following quote:

Marion Nestle, the author of the book “Soda Politics” and a professor of nutrition, food studies and public health at New York University, was especially blunt: “The Global Energy Balance Network is nothing but a front group for Coca-Cola. Coca-Cola’s agenda here is very clear: Get these researchers to confuse the science and deflect attention from dietary intake.”

The Times investigation was kicked off by friend and colleague Yoni Freedhoff:

The [GEBN] website also omitted mention of Coke’s backing until Dr. Yoni Freedhoff, an obesity expert at the University of Ottawa, wrote to the organization to inquire about its funding. Dr. Blair [GEBN vice president] said this was an oversight that had been quickly corrected.

Dr Steve Blair is the vice president of GEBN (full disclosure: I was co-author on a paper with Dr Blair during my MSc, and have posted a video of one of his talks here), and the article quotes him as saying the following (emphasis mine):

“Most of the focus in the popular media and in the scientific press is, ‘Oh they’re eating too much, eating too much, eating too much’ — blaming fast food, blaming sugary drinks and so on,” the group’s vice president, Steven N. Blair, an exercise scientist, says in a recent video announcing the new organization. “And there’s really virtually no compelling evidence that that, in fact, is the cause.”

GEBN has also posted position papers on their website, including this one titled What is Causing the Worldwide Rise in Body Weight?  The below text is the conclusion from the abstract of that paper (emphasis mine).

Reducing caloric intake in whole populations is challenging especially at relatively low levels of energy expenditure, and evidence suggests that there is a critical energy flux threshold for regulating intake to achieve energy balance. Increasing PA, however, may be more achievable than reducing intake. Activity raises caloric expenditure and can offset excess  intake. The implementation of programs to achieve greater PA is therefore vital if the worldwide rise in body weight is to be halted, while we also need to implement programs to help people eat smarter.


In contrast to the Times article, over at Nutrevolve, Kevin Klatt’s view on GEBN is more nuanced (emphasis mine):

The issue with the researchers is that they’ve taken money from Coke for their research, that their research pushes exercise over dietary intake as a cause of obesity (IMO, it’s pretty weak data- their one paper on the topic relies heavily on ‘we can’t trust NHANES’) and they pretty stupidly didn’t disclose the funding on their webpage until it was pointed out to them. While I don’t fully agree with their perspective on obesity (though I do think the energy flux theory is worth further study), to claim that GEBN is a front group and that these researchers are bought out is a far stretch. Like much of the observational evidence that fuels debates surrounding obesity, reverse casuality isn’t considered; anyone who knows Blair and Hill’s work (eg Hill, 1998, 2005 – Blair has published/written extensively about the ‘fat but fit’ paradigm) knows that their opinions on exercise, obesity and treating metabolically unhealthy individuals have been around long before they started this network. However, this isn’t considered in the media coverage that’s selling the shill card pretty hard (though this current article is softer than others I’ve seen).

I disagree somewhat with Klatt here – Dr Blair has written much about the fat but fit paradigm, but I think that’s a different issue (e.g. you can be healthy despite a high body weight).  And I was still surprised to read the above statements from Dr Blair and GEBN, because I have taken very different conclusions from the published literature on the role of sugar sweetened beverages in obesity.  I’m not suggesting anyone has been “bought” by Coke (I find it more likely that Coke would simply fund researchers whose views naturally align with their own – hence why I would wager that Coke likely funds more physical activity research projects than diet projects). But it’s hard to watch this GEBN video, or read their GEBN press release, without seeing the GEBN view as extremely one-sided.

In the past I have summarized my own views on the causes of the obesity epidemic, which I will be reposting here tomorrow.  Later this week, I will also be sharing my thoughts on the relationship between Big Food and Public Health research.  In the meantime, head back over to the Times to read their piece in full.



Category: News | 7 Comments

Walking meetings: a step in the right direction?

Image by Sangy23.

Image by Sangy23

Today’s post comes from Allana Leblanc.  You can find more on Allana at the bottom of this post.

Right next to coconut water, and standing desks, “walking meetings” are the newest buzzwords for the ever trendy workplace.  A quick Google search will show pages of magazine articles and news stories touting the benefits of taking your work to the streets.  Travis has mentioned them a couple times here, and a summer student with the Healthy Active Living and Obesity Research Group gave a compelling overview of why they are beneficial to health.

Not to beat a dead horse, but I want to share with you the results of a recent article on the benefits of walking meetings. But rather than the health benefits of walking meetings, I want to talk about the benefits for creativity.  Because in a series of 4 experiments, Oppezzo and Schwartz show that walk is your first step to a creative day (full text available here).

To test creativity, they used a couple different tests, but basically, during the sitting, or walking conditions, participants were audio recorded while they completed different word association tasks.  After the test was over, they were scored according to novelty and appropriateness of their responses

Experiment 1

Two conditions:

  1. sitting + test
  2. walking on a treadmill + test

Results: Walking on a treadmill produced an average creative output of 60% higher than sitting.

Experiment 2

Three conditions:

  1. sitting + test, followed by treadmill walking + test
  2. treadmill walking + test,  followed by sitting + test
  3. sitting + test,  followed by more sitting + test

Results: The walking condition, was associated with the highest test scores.  Order of the conditions also mattered so it wasn’t just that people were getting better at the tests.  Walking had a carryover effect such that the walking + sitting condition produced higher scores than the sitting + walking condition. The sitting + sitting condition produced the lowest scores for creativity.

Continue reading »

Category: News | 3 Comments