Monday, January 08, 2007


Worrying about your diet is bad for you! Stay happily fat. Ignore media messages about obesity. Those are unusual lessons but they are lessons to be learned from the following findings. Journal abstract follows:

Is Dieting Advice From Magazines Helpful or Harmful? Five-Year Associations With Weight-Control Behaviors and Psychological Outcomes in Adolescents

Patricia van den Berg et al

OBJECTIVE. The purpose of this study was to evaluate the association between frequent reading of magazine articles about dieting/weight loss and weight-control behaviors and psychological outcomes 5 years later in a sample of adolescents.

PARTICIPANTS AND METHODS. Data are from Project EAT (Eating Among Teens), a 5-year longitudinal study of eating, activity, weight, and related variables in 2516 middle and high school students. In 1999 (time 1), participants completed surveys and had their height and weight measured. In 2004 (time 2), participants were resurveyed.

RESULTS. For female adolescents, the frequency of healthy, unhealthy, and extreme weight-control behaviors increased with increasing magazine reading after adjusting for time 1 weight-control behaviors, weight importance, BMI, and demographic covariates. The odds of engaging in unhealthy weight-control behaviors (such as fasting, skipping meals, and smoking more cigarettes) were twice as high for the most frequent readers compared with those who did not read magazine articles about dieting and weight loss. The odds of using extreme weight-control behaviors (such as vomiting or using laxatives) were 3 times higher in the highest frequency readers compared with those who did not read such magazines. There were no significant associations for either weight-control behaviors or psychological outcomes for male adolescents.

CONCLUSIONS. Frequent reading of magazine articles about dieting/weight loss strongly predicted unhealthy weight-control behaviors in adolescent girls, but not boys, 5 years later. Findings from this study, in conjunction with findings from previous studies, suggest a need for interventions aimed at reducing exposure to, and the importance placed on, media messages regarding dieting and weight loss.



Smarter people tend to eat more "approved" food. But what does it mean? It turns out that it is not a raw IQ effect but is mediated via social class. Brighter people are more educated and more education means more indoctrination into conventional health wisdom. The findings do however extend yet again the evidence about the great raw predictive power of IQ tests in most aspects of life. Journal abstract follows:

Childhood Mental Ability in Relation to Food Intake and Physical Activity in Adulthood: The 1970 British Cohort Study

G. David Batty et al.

OBJECTIVE. The purpose of this work was to examine the relation of scores on tests of mental ability in childhood with food consumption and physical activity in adulthood.

METHODS. Based on a cohort of >17000 individuals born in Great Britain in 1970, 8282 had complete data for mental ability scores at 10 years of age and reported their food intake and physical activity patterns at 30 years of age.

RESULTS. Children with higher mental ability scores reported significantly more frequent consumption of fruit, vegetables (cooked and raw), wholemeal bread, poultry, fish, and foods fried in vegetable oil in adulthood. They were also more likely to have a lower intake of chips (French fries), nonwholemeal bread, and cakes and biscuits. There was some attenuation in these associations after adjustment for markers of socioeconomic position across the life course, which included educational attainment, with statistical significance lost in some analyses. Higher mental ability was positively associated with exercise habit, in particular, intense activity (defined by being out of breath/sweaty). The associations between mental ability and these behaviors were similar in both men and women, and they were somewhat stronger for verbal than nonverbal ability.

CONCLUSIONS. It is plausible that the skills captured by IQ tests, such as the ability to comprehend and reason, may be important in the successful management of a person's health behaviors.



Just some problems with the "Obesity" war:

1). It tries to impose behavior change on everybody -- when most of those targeted are not obese and hence have no reason to change their behaviour. It is a form of punishing the innocent and the guilty alike. (It is also typical of Leftist thinking: Scorning the individual and capable of dealing with large groups only).

2). The longevity research all leads to the conclusion that it is people of MIDDLING weight who live longest -- not slim people. So the "epidemic" of obesity is in fact largely an "epidemic" of living longer.

3). It is total calorie intake that makes you fat -- not where you get your calories. Policies that attack only the source of the calories (e.g. "junk food") without addressing total calorie intake are hence pissing into the wind. People involuntarily deprived of their preferred calorie intake from one source are highly likely to seek and find their calories elsewhere.

4). So-called junk food is perfectly nutritious. A big Mac meal comprises meat, bread, salad and potatoes -- which is a mainstream Western diet. If that is bad then we are all in big trouble.

5). Food warriors demonize salt and fat. But we need a daily salt intake to counter salt-loss through perspiration and the research shows that people on salt-restricted diets die SOONER. And Eskimos eat huge amounts of fat with no apparent ill-effects. And the average home-cooked roast dinner has LOTS of fat. Will we ban roast dinners?

6). The foods restricted are often no more calorific than those permitted -- such as milk and fruit-juice drinks.

7). Tendency to weight is mostly genetic and is therefore not readily susceptible to voluntary behaviour change.

8). And when are we going to ban cheese? Cheese is a concentrated calorie bomb and has lots of that wicked animal fat in it too. Wouldn't we all be better off without it? And what about butter? It is just about pure fat. Surely it should be treated as contraband in kids' lunchboxes! [/sarcasm].

Trans fats:

For one summary of the weak science behind the "trans-fat" hysteria, see here. Trans fats have only a temporary effect on blood chemistry and the evidence of lasting harm from them is dubious. By taking extreme groups in trans fats intake, some weak association with coronary heart disease has at times been shown in some sub-populations but extreme group studies are inherently at risk of confounding with other factors and are intrinsically of little interest to the average person.

The use of extreme quintiles (fifths) to examine effects is in fact so common as to be almost universal but suggests to the experienced observer that the differences between the mean scores of the experimental and control groups were not statistically significant -- thus making the article concerned little more than an exercise in deception


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