Obesity and Eating Fast | Hacker News Reader

Obesity and Eating Fast

economix.blogs.nytimes.com

40 pointsrobg26 comments

Researchers once did a study to understand why the French aren't as obese as Americans even though they eat food that have a relatively higher fat content. They based their study on an idea they had about internal and external cues.

Apparently, Americans are more likely to use external cues ("there is still food on my plate") and the French are more likely to use internal cues ("I don't feel hungry anymore") when it comes to deciding when to stop eating.

http://vivo.cornell.edu/individual/vivo/individual20060

I know for myself, the external cue of "there is still food on my plate" is a strong one, since I was raised to always finish my plate. I now do so religiously, but try to set myself up for success by getting smaller portions :).

I also do not like to waste as I have actually seen people in some parts of the world who are malnourished and always hungry... I can't leave food on my plate for that reason and I wish many restaurants would just server me less food. I'd still pay the same price.

2 options: Specifically ask for a half-sized portion, or eat half and take the rest away for lunch tomorrow.

Rapidly shoveling food in your mouth is a great way of gaining weight because you don't notice the point when you stop being hungry. Instead, you only stop when your stomach screams it can't take any more food.

When I was trying to lose weight, I made sure I was eating as slowly as I possibly could. And it worked - I ate less because I got tired of chewing.

That's one of the weakest "correlation" graphs I've seen in a while.

That's one of the weakest "correlation" graphs I've seen in a while.

See the Wikipedia article

http://en.wikipedia.org/wiki/Correlation

and especially its well done graphs

http://en.wikipedia.org/wiki/File:Correlation_examples.png

http://en.wikipedia.org/wiki/File:Anscombe.svg

(one based on a famous article by a statistician) for what correlation coefficients alone do and do not say about relationships among data points.

I know. Did anyone see the r^2 for the correlation?

I was taught by an econometrician that r^2 values don't mean much, but I cannot remember his logic as to why. Maybe something about malleability?

That Anscombe example sheds light on the misuse of r^2. All of those examples have the same r^2 value.

Those are some very nice examples.

However, is there a better/more respected metric for comparing how two datasets are related? Mutual Information perhaps?

I'm not an expert -- more of a hobbyist who is actively trying to improve my statistical chops -- but I don't think there's ever a general metric for this sort of thing. For any statistic it's important to demonstrate that it's being used as intended so that its lay translation means what it seems to mean.

I mean, r^2 isn't all that misleading if your relation really is linear. R^2 plus a graph of the regression would be sufficient. Just taking a look at the residuals of the Anscombe sets easily shows that linear fitting (thus r^2) is inappropriate for sets 2-4.

(btw: if you fit the second Anscombe data set with a 2nd order polynomial, r^2 = 1. Of course, it's pretty clear that there's hardly any error in that set.)

The results aren't really that surprising, given that it takes ~20 minutes between the time you put food in your mouth to the time the brain recognizes satiation. If you eat slower it'll give your brain time to adjust to keep up with how much you've consumed. If you don't you'll keep cramming food in until your REALLY full.

There are many possible causal arrows:

* eat fast => no satiety signal => fat

* empty carb diet => fat, fast binge eating

* high density food => fast, fat

* quality of life focus => (enjoy food => slow, exercise lots => thin)

* workaholic => fast, (no exercise => fat)

Also, I think you could draw a plausible correlation the other way, along the Norway-New Zealand axis and consider the US, Turkey and France the outliers.

It would be interesting to see whether the same correlation holds when you look at individuals. These numbers would make perfect sense if food prep time is included in the "time spent eating" measure (the page summarizing the study doesn't say).

If there actually is any correlation, maybe it's because in countries where people 'spend longer eating' there is a better focus on eating good quality food (rather than any direct correlation e.g. wolfing down food means you are more likely to put it on as weight).

I lived in Geneva for a while and we would always take at least a one hour lunch. There is hardly anywhere to get 'fast food', even in the city centre. And I certainly notice less 'heffers' there than when I am back in the UK.

There are two things which can be taken from that graph. Americans eat quickly and Americans have an obesity problem (certainly along with Mexico and the commonwealth). I'm sure that any correlation is a by product of a deeper difference in cultural relationship with food that results in eating slower. My point being making people eat slower in the US would only move their position on the graph horizontally.

I'd also like to see a list of the diets and living habits of people in these countries. How is their work/life balance?

When I was in France (granted it was 1995), I saw that a lot of people smoked, which could explain how they stay thin despite a lot of fatty foods.

When I was in Tokyo last year, some people smoked, but their diet is rich in vegetables, fish, and rice.

My wife's 35 year old brother-in-law eats so fast he resembles a vacumn cleaner, yet he is a skinny as a stick. I eat slow and in small quantities and have a bit of belly.

I suspect that the reasons for obesity are myriad and are complexly intertwined (though at the most basic level simply eating fewer calories and getting regular exercise can have a big impact).

Off topic, but wouldn't your spouse's in-laws be directly related to you? That would make your wife's brother-in-law your brother. Am I missing something?

He means his wife's sister's husband?

I was surprised by the difference in obesity rates between the US and Canada. Both have similar eating time values, and I generally consider them culturally and economically pretty similar. But still Canada's obesity rates are much lower than in the US.

Keeping your body warm requires energy.

For me it's true. I eat very slowly and I'm thin (some would even say that I'm a bit too thin). Also, all the fat people I know eat faster than me.

That line doesn't appear to go there.

Anyone notice how the ex-British Empire dominates the list? How about a correlation to angloindex?

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