Obesity drives up U.S. fuel appetite

THE WASHINGTON TIMES ^ | October 26, 2006 | Jennifer Harper

[M1Tanker]

Then we should get rid of spare tires, jacks, survival gear if cars (blankets, hats, coats, flashlights) and also outlaw large stereo systems, cd cases, wearing haevy boots while driving, etc.

For that matter, why not just outlaw cars? Except for leftist elites of course.

Even though the weight of many vehicles have gone up (much more than 200 lbs) and yet they have as good or better fuel economy. This was in other links I noted.

The data in the Was Times article cited is useless because it takes only two measures a statistical weight of 'average Americans' and fuel consumption. They then make the evidence fit the 'crime'. The study ignores the addition of catalytic converters and other government mandated items. It ignores the proliferation of energy demanding items in modern cars (A/C, defoggers, stereos, navigation systems, TV/DVD/VCRs, 12 volt coolers, etc). The study also ignores driving habits (somehow concluding that as we 'continue to gain weight' we are more aggressive).

Unless all the factors are included, cross referenced, and figured into the total, this report is about as accurate as a political poll.

[Publius6961]

Kill 'em all, dammit!
Put them in the gulag next to the smokers.

[Publius6961]

This is an utterly BS story designed to push a point of view. Maybe Jacobsen, the "computer scientist," could more profitably do a study on the ridiculous amount of excess gas consumption caused by badly-timed stoplights. Or obese SUVs.

Hit a personal nerve, did he?
Captain obvious says... every incremental increase adds up.

Ignoring any one factor does not invalidate the underlying physics.

[Paco]

Does this take into consideration that people are taller, therefore heavier? Weight alone doesn't mean anything. It's all relative. I recently went to a nieces graduation...the kids in her high school graduating class are DEFINITELY taller (therefore heavier) than kids in my class (1977).

[newgeezer]

... which is what I meant by, "if that's not already adjusted for average height, it needs to be."

[Blackirish]

Don't blame me I'm skinny and mostly ride public trans.....

[newgeezer]

Isn't it funny how many posters will read an article like this—or, maybe just the headline—and have an apoplectic fit about stuff that, in actuality, isn't even there?

[Bernard Marx]

Hit a personal nerve, did he?

So are you a member of the Obesity SS? Maybe you have some soap-making projects in mind? Certainly all factors contribute. There's also such a thing as being blitheringly silly. One of the biggest factors in excess American gasoline consumption is the overabundant presence of huge grossly overweight SUVs carrying one (usually incompetent or hostile) person. Add that to your "underlying physics" and rotate on it a little. If you wish to discuss anything "personal" with me let's work it out via Freepmail.

[dfwgator]

[LeGrande]

So I think the article probably has their numbers about right.

lets see ^_^. we use 983 million gallons of gas more each year than we did in the slimmer '60s. That amount could fill 1.7 million gas tanks.

983/1.7 = 578.24 gallon tanks. I don't think so.

I tend to mistrust articles on math whose authors don't have a grasp of basic math.

if 200lbs causes a 1 mpg drop and 20 mpg is the fleet avg., that would be a 5% drop and 20 lbs would be a 0.5% drop.

On flat highway driving the physics are that adding 200 lbs of weight would have almost zero impact. The only time extra weight hurts fuel economy is in acceleration, so in constant stop and go traffic it would hurt the fuel economy, but if you coast to a stop rather than slamming on the brakes the extra weight helps the car coast further. So driving habits have a much greater effect on fuel economy than the extra weight.

[Myrddin]

We have 100 million more people in the population compared to 1960. That's a lot more significant cause of additional consumption than the average weight of the passengers.

[CaptRon]

Carrying too many Dixie Chicks CDs and a lunch of tofu does the same thing

[guitfiddlist]

2,800 lb passenger car. 175 pound person or 275 pound person. Hmmm, let's see. 100 lbs additional weight on a 2,800 pound vehicle. Yep, that 3.8% weight increase is going to kill us all.

Thanks. Saved me the time and effort to belabor the obvious. And as for you, Jennifer Harperrrrrr of the Washington Times, a valley girl journalist ditz should take care when writing about engineering statistics. But then again, you might even get Couric's job. It's all about the glitz, yaknow.

[Tamar1973]

Step away from the buffet and save gas.

[pepsi_junkie]

Yes, I stated that increase in vehicle weight requires more fuel. However the article talks about billions of gallons more fuel used each year. Show me how our obesity translates into that number. I dont see it in the article. Is the number a few thousand more gallons? Is it a million? Is it tens of billions? Given all the other changes society has undergone in the same time, there would seem to be no reliable way to show that the gain in average weight is more than a trivial portion of the overall fuel consumption figures. That was my point, not that weight is not a factor at all.

[pepsi_junkie]

Every vehincle carying 24 pounds more? But there are many more vehicles. So let's keep the number of vehicles constant. But the vehicles have better efficiency! So let's assume constant gas mileage. But the fuel is different now than it was then, we add stuff to it for environmental frieldliness! So lets assume that modern blended fuels are exactly equivalent to the old leaded stuff in terms of energy available in a gallon. So, we're all driving 1960 Cadillacs (not all of us, actually, just the number of people who drove back in 1960) and we assume those people are now 24 pounds heaver, how much more fuel would they use?

But the fact is there are more cars on the road, and even if they're all driven by Twiggy they use gas. That adds to the total used. As well as other factors. All this article says is "we use more fuel, we're fatter, therefore the increase in fuel consumption is because we are fatter". In part, yes. But is that impact a bit like saying I'm heavier when my hair is wet? A fact yes, but as a percentage of my overall weight not an important factor.

[newgeezer]

Your first paragraph implies you have yet to realize the point of the article is how much fuel it's costing to carry around 24 pounds of extra weight per person.

Forget about 1960. There is no point in discussing 1960 driving habits and/or vehicles and/or anything else related to 1960. 1960 is nothing more than a point of reference for the weight gain.

It's fascinating. Not necessarily significant. As I said initially, it's useless trivia.

[newgeezer]

lets see ^_^. "we use 983 million gallons of gas more each year than we did in the slimmer '60s. That amount could fill 1.7 million gas tanks."

983/1.7 = 578.24 gallon tanks. I don't think so.

It makes sense if you consider that's filling 1.7 million average gas tanks over the course of a year:

578 gallons / 52 weeks = about 11 gallons per week.

[newgeezer]

Show me how our obesity translates into that number. I dont see it in the article.

The article says, "His analysis showed that every extra pound of human body weight in a vehicle equals an additional 39 million gallons of extra gasoline use collectively in a year."

Let's sanity-check that number. (If I make a mistake here, I'm sure anyone who catches it will kindly point it out. :)

39 million gallons per year = 750,000 gallons per week. How many vehicles are we talking about? I don't know and, for the purpose of a sanity check, I don't need to look it up.

Let's say it's 150 million vehicles. Then, 750K gallons translates to 0.005 gallons of fuel per vehicle to carry that extra pound around for a week.

If we use an average of 11 gallons per week (see post 58), 0.005/11 = 0.045%. So, every extra pound we carry in our cars results in something on the order of 0.045% reduction in fuel mileage. Carry an extra 100 pounds, it reduces MPG by 4.5%. (This assumes the relationship linear, which it is not.) So, if we normally get 21 MPG on the highway, an extra 100 lbs. is costing us 1 MPG, taking us down to 20 MPG. That seems high to me but, not unreasonably so.

In view of the number of 'guesstimates' I made along the way, I'm satisfied his data and number crunching produced reasonable results. Therefore, I think it passes the sanity check. If the numbers had come out to, say, a 30% or 40% penalty for 100 lbs, I'd have to say it failed the sanity check. Likewise if it came out to, say, 1% or less.

Oh, and by the way, this sentence in the article caused me some concern: "He compared national health data and passenger-car fuel consumption from 1960 to 2003 to find that because of a heftier population, we use 983 million gallons of gas more each year than we did in the slimmer '60s." I suspect it should probably read, "He compared national health data from 1960 and 2003, and looked at passenger-car fuel consumption to find that because of a heftier population,..." (darn 'journalists' anyway!). The phrase, "because of a heftier population" says it all. And, as I have said previously, that's as simple as figuring out how much it costs today to carry additional weight in the car.

Sorry if that was too long and boring. Regardless, I had fun with it. I think I'll go home and have the kids figure it out now. :-)

[383rr]

The attack on fatties and 'Big Food' is on.

http://www.suntimes.com/news/metro/110367,1025fat.articleprint

Looks like the surgeon general should resume his duties. He could be screeching about "no safe level of trans-fats."

I guess he's happy working working at the hot-tub-club now.