Obese Kids Drink As Much Pop As Skinny Kids?
Wednesday, February 5, 2014
Among all of the popular targets for population-based solutions to the obesity dilemma, sugar-sweetened beverages (SSB) probably head the list.
There is indeed no arguing with the fact that the sugar in these beverages adds a substantial amount of calories to the average Canadian’s diet – calories, with little (if any) nutritional value. Thus, in any simplistic equation of “calories in and calories out”, SSBs would certainly stand out as a prime candidate for driving obesity.
Unfortunately, this notion (at least the simplistic variants of this notion) are not as unequivocally supported by the actual research on this issue, as some would have us believe.
Case in point is the latest study on this issue by Lana Vanderlee and colleagues from the University of Waterloo School of Public Health (host of the upcoming 4th National Obesity Student Meeting, June 18-21, 2014), published in the Journal of School Health.
The study looks at data from 10,188 youth (ages 13-18) from Hamilton and Thunder Bay, Ontario, and Prince Edward Island (PEI) in 2009 to 2010, who answered 12 questions regarding beverage consumption during the previous day, along with self-reported height, weight, physical activity levels, and demographic information.
While four out of five youth reported to have consumed at least one SBB on the previous day, almost one in two reported consuming three or more!
Although there were interesting geographic differences in SSB consumption, the researchers found virtually no relationship between BMI and SSB consumption, no matter how they analyzed the data.
Funnily enough, PEI, where kids reported the lowest SSB consumption, turned out to have the highest number of overweight kids.
Despite all the usual caveats with studies based on self-reported rather than objectively measured data, one thing is clear: if SSBs are indeed a relevant driver of the obesity epidemic, the data certainly don’t shout it out.
Obviously, one explanation could well be that the methodology of the study was not robust enough to identify this relationship (although I am certain that had a positive relationship been found, this study would have been widely paraded as conclusive evidence to support the immediate ban of SSBs).
On the other hand, a rather simple explanation for this finding may be that no such relationship exists. Indeed, it is scientifically not at all unreasonable, when your data fail to support your hypothesis, to question the hypothesis.
This is not to say that copious consumption of SSBs may not be detrimental to health – that may well be the case.
But it does seem that the popular story line suggesting that SSBs are anywhere as important a “cause” of the obesity epidemic as proponents of this hypothesis make them out to be, certainly needs to be taken with a grain of salt.
This issue becomes even more important, if such efforts distract us from identifying and addressing the “real” causes of the problem (which I am willing to wager, in the end, may well have surprisingly less to do with either diet or physical activity than we think).
@DrSharma
Edmonton, AB
Wednesday, February 5, 2014
Hello Dr Sharma,
I just read with interest your last entry blog about SSB and it’s link to obesity. I was talking about this with my colleagues and some said that you receive money from Coke and that is why you are saying there is no link. I was curious to know your point of view.
Thank you,
Wednesday, February 5, 2014
Haha – I wish! Nope, the post doesn’t actually say SSBs are good for you, just that the link to obesity may not be as scientifically robust as many people think. And of course I counsel my patients to cut SSBs from their diet. I just think that it is interesting how people develop these strong opinions on things and when you look at the actual science, you wonder what these opinions are based on.
Wednesday, February 5, 2014
Other studies show a link between SSBs and body weight but the effect size is very small, accounting for about 2% of weight gain over time. In other words, 98% of weight gain is driven by other factors.
Thursday, February 6, 2014
Looking back at my own teen years from 75, I and my friends consumed sugayr stuff including beverages all the time, despite my parents entreaties that fruit was healthy. So, that sugar and fructcose was in addition. Few of us were obese, and many of us didn’t even exercise that much (good thing — it would have made us hungrier and we would have eaten more junk food).
Metabolically, I think we were able to handle that tsunami of sugar at that period. Therefore, I can easily believe that now there other factors at work at that age that are driving the obesity, but what?
I have taken thee liberty of sending your post on to “Obesity and Energetics,” which monitors reports, papers, etc. in this area. You probably know of it. If not, I’m sure yu’ll find it of great interesest.
Thursday, February 6, 2014
I am 66 years old, 6 foot 6, during the past year and half I lost 160 lbs.
Even if SSB’s account for 2% of weight gain, I can not see how I could have manage my weight loss by cutting down on some sugary products and not others.
When you are overweight, you will not solve the problem by cutting down on sugars and eating more fruits and vegetables….. You need to do that plus at the same time, go cold turkey on a whole array of foods and habits, in other words, a major change of lifestyle.
SSB’s a simply not to be included in the new lifestyle. The matter become’s more important after loosing the weight. During a few years I was eating approximately 3,500 calories per day, no exercises, with no change in weight. Today, after 4 months of weight maintenance, I definitely gain weight if my calories intake average is more than 1,550 daily. Trust me, I count every one of those calories, furthermore, my new lifestyle includes exercises, and two hours of reading every day about nutrition.
Friday, February 7, 2014
The point about self-reporting deserves more attention than simply mentioning it as a “usual caveat.” It’s well known that people — especially obese people — tend to wildly under-report their caloric intake. This study is essentially worthless.
Saturday, February 8, 2014
People vary in response to SSBs due to differences in physiological and biochemical makeup. Consequently, averaging responses may to produce null results. Perhaps a better approach would be to have obese and normal weight subjects reduce or eliminate SSB consumption for a time and measure the impact on BMIs, fat stores, glucose levels, and triglyceride levels. The research of Peter Kuo contains clues as to what researchers might learn from such an approach. Excerpt:
The difference in plasma lipid response of healthy normolipemic subjects to different types of carbohydrate was found to be minimal. Five healthy students were found to maintain their serum lipid levels within the normal range despite relatively high sugar content of their “home diet.” The students did not develop a significant hyperlipemia even after their average dietary sugar content was raised to 285-300 g/day for 3 weeks. This amount of dietary sugar constituted about 30-40% of their daily caloric intake. Feeding experiments suggested that it was necessary to raise the dietary carbohydrate to 85-90% of the total calories, and to supply the major proportion of it as sugars, before significant degrees of hyperglyceridemia could be induced in subjects who did not have disturbances in carbohydrate and glyceride metabolism. http://ajcn.nutrition.org/content/20/2/116.full.pdf?origin=publication_detail