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Monday, August 10, 2009

We're Happy happy Happy With our Fat - or maybe not

We are amazing. We adapt to anything. Including our own states when they are less than our once-cherished ideals. We settle. We get on. We make the best of. Or so it seems. It seems that since 1987, at least white folks' idea of an ideal weight has increased - higher BMI is ok'er. And with that, it seems, a desire to move or adjust diet has gone down. Oh dear.

A new study - indeed it's published in the future because its date is Aug 15, 2009 and it's not quite that date yet - looks at exactly the steady progress of how heavier people have become happier with heavier selves. This is pretty amazing on the one hand considering how much we're inundated with images of the Super Lean, but then perhaps not considering the reality of the Super Size (and it's another kick at set point theory being set, ha!)

In the following, therefore, i'd like to review that study and its focus pretty much on concerns around food and movement that come out of the data, and top it off with some work that considers a focus on work other than diet and movement may be in order.

And so to begin, here's the abstract of our perception changing study.

Am J Epidemiol. 2009 Aug 15;170(4):456-63. Epub 2009 Jun 22.

Ideal weight and weight satisfaction: association with health practices.

York University, Toronto, Canada. jennkuk@yorku.ca

Evidence suggests that individuals have become more tolerant of higher body weights over time. To investigate this issue further, the authors examined cross-sectional associations among ideal weight, examination year, and obesity as well as the association of ideal weight and body weight satisfaction with health practices among 15,221 men and 4,126 women in the United States. Participants in 1987 reported higher ideal weights than participants in 2001, an effect particularly pronounced from 1987 to 2001 for younger and obese men (85.5 kg to 94.9 kg) and women (62.2 kg to 70.5 kg). For a given body mass index, higher ideal body weights were associated with greater weight satisfaction but lower intentions to lose weight. Body weight satisfaction was subsequently associated with greater walking/jogging, better diet, and lower lifetime weight loss but with less intention to change physical activity and diet or lose weight (P < style="font-weight: bold;">Although the health implications of these findings are somewhat unclear, increased weight satisfaction, in conjunction with increases in societal overweight/obesity, may result in decreased motivation to lose weight and/or adopt healthier lifestyle behaviors.


First, it's cool to have a study say we're not exactly sure yet what to make of these finding, but something's going on. Second, the findings themselves are pretty interesting - especially considering the main sample is from three times more men than women, and this is unusual in the obesity area where folks tend to focus more on women.

So what's going on here?

The authors are motivated by a simple, intriguing question: since BMI has gone (and continues it seems to go) up, and so many people (65% in the US) are now classed as overweight, has the perception of what is a "normal" weight changed? There are some interesting tensions in that question: the research that shows obese individuals perceive higher body weight as healthy and attractive - that's one direction - and the media's still constant drive towards the other extreme with associated research showing resulting body dissatisfaction - that's the other. So where are we at, culturally, with perceptions of what's normal?

Cool question

Approach
So the researchers hit the Cooper Clinic and looked at the data from 1987 to 2001 as part of the Aerobics Center Longitudinal Study. Only folks with at least 15 measures over that period were considered. It's amazing to find a data set that's relatively unchanged in the data gathering model for such a period. There are rich questions asked about health history here.

One of the key questions in the intake form is about self-reported ideal weight.

Finding: who's "ideal weight" view goes up? What the data showed is that "the slope of the rise in ideal body weight between 1987 and 2001 was greatest in obese and young adults (0.18 kg/year to 0.25 kg/year) and the smallest in older adults (–0.07 kg/year to 0.01 kg/year)."

Who's satisfied with their weight - over time? "Only 2% of obese men and one obese woman reported being satisfied with their weight. BMI, examination year, and ideal weight were all independent predictors of weight satisfaction...In the same model, with each passing examination year, weight satisfaction was 3%–4% higher (P <0.01)...Higher cardiorespiratory fitness also was independently associated with greater weight satisfaction (men: OR = 1.23, 95% CI: 1.18, 1.29; women: OR = 1.35, 95% CI: 1.23, 1.48) and less intention to lose weight (men: OR = 0.82, 95% CI: 0.76, 0.89; women: OR = 0.82, 95% CI: 0.69, 0.97; Ptrend <>"


What did folks more satisfied with weight do? The folks more satisfied with their weights had lower BMI's and lower percentages of body fat, but they also MOVED.

Weight satisfaction was also associated with higher levels of walking/jogging per week, higher cardiorespiratory fitness, less restrained eating, consumption of more fruits and vegetables, and higher self-rated health compared with those reporting body weight dissatisfaction (all P ≤ 0.01). Body weight satisfaction was associated with greater distance walked/jogged per week compared with those reporting body weight dissatisfaction, whereas BMI category was negatively associated with distance walked/jogged per week (men—overweight or obese: 18.9 km/week vs. 15.8 km/week, lean: 20.8 km/week vs. 18.6 km/week; women—overweight or obese: 14.4 km/week vs. 14.3 km/week, lean: 18.2 km/week vs. 17.3 km/week, respectively) after adjustment for age, ethnicity, and smoking for both men and women (P < 0.001).
What seems interesting to me here is that there is not a lot of difference - really - in the amount moved per week between the satisfied and the dissatisfied groups. 18.9km per week vs 15.9? 3km (about two miles) separating BMI levels of happiness and health? Food for thought there. And speaking of food for thought.

For men, there was a significant interaction between BMI category and body satisfaction on fruit and vegetable consumption such that only the overweight or obese men dissatisfied with their body weight consumed significantly fewer fruits and vegetables (overweight or obese: 14.9 vs. 13.6 per week; lean: 15.1 vs. 15.1 per week; P = 0.01). For women, only a positive main effect of body weight satisfaction was observed (overweight or obese: 17.8 vs. 15.7 per week; lean: 17.4 vs. 15.6 per week; P < 0.001).
So guys who are overweight to obese and dissatisfied with their bodyweight also tend not to eat their veggies. Hmm. Interesting habit.

Intention to change. Almost everyone (93% men and 95% women) of the group who said they were dissatisfied with their weight said they planned to change their diet. About the same ratio (95%/94%) of all men and women said they planned to "change their stamina or physical condition)". 53%/63% of the whole group said they planned to change both. Folks who were happy with their weight had less intention to change their diet or workouts (duh?)

Lifetime: the magic 100. Men who'd lost more than 100 pounds over their lifetime had a lot of stuff going on than the satisfied with their weight.
  • higher BMI
  • higher ideal weight
  • more likely to report current dieting
  • subtly lower cardiovascular fitness
On the other hand with women, BMI correlated directly with weight satisfaction.

What's it all mean?
here's where the researchers reflect on their findings, and what they find, overall, is that ideal reported weight has gone up (at least in this very large group) overall, but "particularly among obese individuals."

There main concerns is that younger overweight/obese folks are progressively happier, it seems with higher body weights (going up .3kg/year). Here's the crucial thing: higher body weight correlating with lower ratings of body weight dissatisfaction was also coupled with less intention to move, less consumption of fruit and veg, but also ironically more caloric restriction cycles with higher total pounds of fat lost (but not kept off) over a life time.

In other words, a lot of dieting cycles without super food choices that don't translate into persistent weight loss.

What the researchers are unsure of, is how to leverage these findings strategically for effective change. Is weight disatisfaction a good thing to help motivate change? How would that work, though, without a lot of readily available support? - Good questions.

These resaerchers are also concerned that of those disatisfied in weight who express an interest to change their diet don't also express an interest to change their activities - they feat that without getting physical activity into the mix, weight loss doesn't stick. I'm not so sure about that but am keen to check out the papers they cite to support that concern. If you wish to do so, too, here are the sources:

  1. Diaz VA, Mainous AG III, Everett CJ. The association between weight fluctuation and mortality: results from a population-based cohort study. J Community Health (2005) 30(3):153–165.[CrossRef][Web of Science][Medline]
  2. Nguyen ND, Center JR, Eisman JA, et al. Bone loss, weight loss, and weight fluctuation predict mortality risk in elderly men and women. J Bone Miner Res. (2007) 22(8):1147–1154.[CrossRef][Medline]
  3. Rzehak P, Meisinger C, Woelke G, et al. Weight change, weight cycling and mortality in the ERFORT Male Cohort Study. Eur J Epidemiol (2007) 22(10):665–673.[CrossRef][Web of Science][Medline]
  4. Provencher V, Bégin C, Tremblay A, et al. Short-term effects of a "health-at-every-size" approach on eating behaviors and appetite ratings. Obesity (Silver Spring) (2007) 15(4):957–966.[CrossRef][Medline]
  5. Saris WH, Blair SN, van Baak MA, et al. How much physical activity is enough to prevent unhealthy weight gain? Outcome of the IASO 1st Stock Conference and consensus statement. Obes Rev. (2003) 4(2):101–114.[CrossRef][Medline]
  6. Martins C, Robertson MD, Morgan LM. Effects of exercise and restrained eating behaviour on appetite control. Proc Nutr Soc. (2008) 67(1):28–41.[CrossRef][Web of Science][Medline]

Today indeed in Science Daily, there's another cry to add to the above that the sedentary are setting themselves up for huge health collisions. Move it Move It. But as i'll come to below, the question may be if movement is such a great thing, why aren't folks doing it, hmm? Quit yelling at doctors to tell patients to move. Where's the support? This is sort of what the speaker, Steven Blair, is quoted as saying, too.

We need numerous changes to promote more physical activity for all, including public policies, changes in the health care system, promoting activity in educational settings and worksites, and social and physical environmental changes. We need more communities where people feel comfortable walking. I believe psychologists can help develop better lifestyle change interventions to help people be more active via the Internet and other technological methods.
but i digress...

Limitations

The authors acknowledge that while the data they have is a super sample size looking at the same folks over a considerable amount of time (a) it's 95% white folks and (b) the measures are limited. For instance diet and movement were only assesed by single points like fruit and veg consumption and walking/jogging distance. And of course, these data are all self-reported, not objectively measured.

But where self-reporting might normally be an issue in a study if that's the sole measure, it's intriguing the authors highlight it, since after all, this study is about self-perception - and it's intriguing to see how one self-reports practice against attitude - regardless of objective accuracy - but maybe that's just me. And just in this case.

humans on the spaceship in Wall-E are sedentary blimps (above)
who see themselves as svelt (below)


Bottom Line
People (at least in the ACL study) are happier being heavier. That their ideal weights have increased across the board. Higher BMI's are ok. And this mayn't be ok. Let me quote the authors:

In conclusion, we have provided evidence that, in the Aerobics Center Longitudinal Study group, there have been secular increases in ideal weight perception, which relate to increased body satisfaction for a given BMI. Body weight satisfaction is associated with lower intentions to change weight, physical activity/stamina, or diet. In combination with the known consequences of obesity, failure to change lifestyle factors may further compound future health problems.
Another Line
While these authors' work shows a thought-provoking trend around getting comfy with being heavier and more sedentary, work by Susan Roberts from Tufts, and her colleagues, has looked more at some of the *why's* behind the effect that gets folks overweight in the first place: eating more.

The authors of the current study touch briefly on the success of various approaches that look less at calories and more at behaviour/attitude around food, and say more work needs to be done to see how successful such non-calorie focused approaches are, and that may be true.

But when looking at Roberts' work, it's hard to deny what her colleague Nicolas Hayes and she found in looking at a particular age group of gals
1: Obesity (Silver Spring). 2008 Jan;16(1):52-8.

Aspects of eating behaviors "disinhibition" and "restraint" are related to weight gain and BMI in women.

D.W. Reynolds Department of Geriatrics, University of Arkansas for Medical Sciences and Central Arkansas Veterans Healthcare System, Little Rock, Arkansas, USA. NPHays@uams.edu

OBJECTIVE: The causes of adult weight gain leading to obesity are uncertain. We examined the association of adult weight gain and obesity with subscales of eating behavior characteristics in older women.

METHODS AND PROCEDURES: Current height and weight, eating behavior subscales (disinhibition subscales-habitual, situational, and emotional; restraint subscales-flexible and rigid; hunger subscales-internal and external) as assessed using the Eating Inventory (EI), and self-reported body weight at six prior age intervals were reported by 535 women aged 55-65 years. Multiple regression analysis was used to examine the relationships between EI subscale scores and weight change from the age interval of 30-39 to 55-60 years and current BMI.

RESULTS: The strongest correlate of weight gain over 20 years was susceptibility to overeating in response to everyday cues within the environment (habitual disinhibition; partial correlation coefficient (r) = 0.25, P < r =" 0.17,"> and susceptibility to overeating in response to specific situations such as social occasions (situational disinhibition) was not associated with weight gain. Flexible control of dietary restraint attenuated the influence of habitual disinhibition in particular on weight gain and BMI, and was less effective in attenuating associations of emotional or situational disinhibition.

DISCUSSION: Lifestyle modification programs for prevention and treatment of adult-onset obesity currently focus on reducing situational and emotional overeating; the results of this study suggest that a stronger emphasis on strategies that target habitual overeating may be warranted.



In other words, what work Roberts' has been doing for the past while keeps showing is the strong correlation between eating as a response to particular situations and stressors. Consequently, one might say that looking at diet and activity alone (as the ACL study review above about ideal weight perception) is likely not going to be a solution for meaningful and lasting change towards health and healthy body weight.

Consider that the self-reporting in the ACL shows that the folks most dissatisfied with their own weight are those most likely to be dieting and have lost more weight overall than others more satisfied. Roberts' and Colleagues work tends to suggest that unpacking what's going on there and helping folks with those habitual responses may be key. She is certainly not alone in this view, but her work puts numbers and facts on this approach: dealing with habits is tough, but critical for health and well being.

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