Philip Alcabes discusses myths of health, disease and risk.

The Myth of Normal Weight

Don’t miss Paul Campos’s commentary on overweight and obesity in today’s NYT.  Responding to the latest report by Katherine Flegal of CDC and coworkers, Campos points out that

If the government were to redefine normal weight as one that doesn’t increase the risk of death, then about 130 million of the 165 million American adults currently categorized as overweight and obese would be re-categorized as normal weight instead.

The report by Flegal et al., published this week in JAMA, is a meta-analysis of 97 studies on body-mass index (BMI) and mortality.  This new analysis found that mortality risks for the “overweight” (BMI 25-29.9) was 6% lower than that for “normal” BMI (18.5-24.9) individuals.  And those in the “grade 1 obesity” category, with BMIs from 30 to 34.9, were at no higher risk of dying than those in the so-called normal range.   Only those with BMIs of 35 and above were at elevated risk of dying, and then only by 29%.

In other words, people who are overweight or obese generally live longer than those who are in the normal range.  Only extreme obesity is associated with an increased probability of early death.

Flegal and colleagues already demonstrated most of these findings using administrative data, in an article appearing in JAMA in 2005.  There, they reported no excess mortality among people labeled “overweight” by BMI standards, and that about three-quarters of excess mortality among the “obese” was accounted for by those with BMIs above 35.

What’s notable about this week’s publication is that it has attracted the attention of some heavy hitters in the media.  Pam Belluck covered the JAMA report for the NYT.  Although her article seems more interested in propping up the myths about the dangers of fat than in conveying the main points of the new analysis, Belluck does acknowledge that some health professionals would like to see the definition of normal revised.

Dan Childs’s story for ABC News gives a clear picture of the findings, and allows the obesity warriors, like David Katz of Yale and Mitchell Roslin at Lenox Hill, to embarrass themselves — waving the “fat is bad” banner under which they do battle.  MedPage Today gives the story straight up.   In NPR’s story, another warrior, Walter Willett of Harvard, unabashedly promoting his own persistently fuzzy thinking, calls the Flegal article “rubbish” — but the reporter, Allison Aubrey, is too sharp to buy it from someone so deeply invested.  She ends by suitably questioning the connections of BMI to risk.

Campos’s op-ed piece does the favor of translating the Flegal findings into everyday terms (and without the pointless provisos that burden the NYT’s supposed news story):

This means that average-height women — 5 feet 4 inches — who weigh between 108 and 145 pounds have a higher mortality risk than average-height women who weigh between 146 and 203 pounds. For average-height men — 5 feet 10 inches — those who weigh between 129 and 174 pounds have a higher mortality risk than those who weigh between 175 and 243 pounds.

Is the hysteria about overweight and obesity is over?  I’m sure not.  In today’s article, Campos — who was one of the first to explode the fiction of an obesity epidemic, with his 2002 book The Obesity Myth — reminds us of a crucial fact about public health:

Anyone familiar with history will not be surprised to learn that “facts” have been enlisted before to confirm the legitimacy of a cultural obsession and to advance the economic interests of those who profit from that obsession.

There’s too much at stake with the obesity epidemic for our culture’s power brokers to give it up so quickly.  One day, some other aspect of modernity will emerge to inspire dread (and profits).  In the meantime, we might at least hope to see some re-jiggering of the BMI boogeyman.

 

The Health Department at Work

I was pleased to receive a phone call from the NYC Department of Health and Mental Hygiene  and to be selected to participate in a “health survey.”  The questions offered a fascinating insight into the agency’s preoccupations — and what sorts of impropriety obsess its leadership nowadays.

It’s reassuring that the Department wants to be able to estimate how many New Yorkers lack health insurance and, separately, lack a regular health-care provider, and asked questions about those things.  And I was impressed that the survey designers thought to ask whether, the last time I sought help for a medical problem, it took a long time to get an appointment.

And then came some predictable How Are We Doing? questions:  Have I had a flu immunization in the past 12 months? (No, thank you, I’m not convinced that it works…  Okay, I didn’t say that, the survey taker seemed young and too earnest for serious critique, so I just said “No.”)  At least two doses of hepatitis B vaccine at some time in the past?  When did I last have a colonoscopy?

But there was the question about whether I have used oxocodone or hydrocodone (OxyContin or Vicodin) without a prescription, or outside of the prescribed dosage.  The Department has just announced a new campaign to stop people from using pain killers too much.

There was the question about whether I’m exposed to cigarette smoke in my household.

There was a question on whether my household has a disaster plan.  No, we don’t.  We have a couple of flashlights, some water, and a bottle of scotch.  Will that do?  We’re grown-ups, we don’t have pets or little children to look after.  We’ll work something out.

(But I didn’t say that to my earnest interviewer, either.  I have a feeling they don’t find whiskey to be humorous, over there at the health department.  In fact, they had some very specific questions about alcohol consumption, amount and frequency.)

There were questions about how often I exercise vigorously.  How often I exercise moderately.  How often I exercise lightly.  How long I engage in said exercise when I do do it.  Very interested in exercise, our health department.

There was the question as to how many servings of fruit or vegetables I ate yesterday.

And then, onward to mayor Mike Bloomberg’s white whale:  sugar-sweetened beverages!  Mayor Mike is going to ban serving soda or other sweet beverages in large sizes — and he’s not asking for a new law (which might not pass), just a go-ahead from the city’s eleven-person Board of Health, all appointed by the mayor, chaired by the city’s cheerleader for “healthy lifestyles,” health commissioner Thomas Farley.   A restaurant trade association, the Center for Consumer Freedom, responded to news of the mayor’s intention with an amusing ad in today’s NYT, portraying Bloomberg as The Nanny.

The survey questions:  How often do I drink soda or bottled iced tea?  What about beverages to which I add sugar myself, like tea or coffee?

And, now that we were deep into the zone of health officials’ self-stimulation:  how many (a) women and (b) men had I had sex with in the past year?  Did I use condoms?  And, had I used the Internet to meet a sex partner in the past 12 months?

So much for health.  Now we know what haunts the dreams of the self-righteous mayor and his bluenose health commissioner:

Pain relief.

Fat people.

Vigorous exercise.

Pleasurable foods.

 Sex.

Reading this list, you would have to be forgiven for thinking that these men, Bloomberg and Farley, have been living in a monastery since, say, the 14th century.  In fact, if they were really clergymen instead of officials, they would leave us alone about how we eat and sweat and screw.  At least in between sermons.

But thanks for calling.

 

 

 

Childhood Obesity: NYC’s Little Lies, Big Self-Congratulation

There is very little evidence that obesity is harmful to young children.  So I have to ask why NYC’s Department of Health and Mental Hygiene feels so strongly that fat schoolchildren should be forced to slim down.  And why it’s so eager to congratulate itself today on its policing of eating behavior — see reports by WSJ, Bloomberg, CBS (with photos of fat kids!), Huffington, and many other sources.  Why would the city’s health agency lie in order to claim that its jihad against a not-very-convincing evil has been successful?

The subject is a report published by CDC today claiming that obesity among NYC schoolkids in grades K through 8 has decreased 5.5%.

The city’s health commissioner, Thomas A. Farley has been true to the shades of history’s empty-headed warriors.  Farley announced that the drop in obesity prevalence is a “turning-point in the obesity epidemic” although it “does not by any means mark the end.”

A missed photo opp:  Dr. Farley standing on top of a fat child, holding up a sign reading, “Mission Accomplished.”

Farley is zealous about controlling people’s behavior and contemptuous of facts (nobody will ever accuse him of being an intellectual, either).  He blogs about his own work for the exclusive reading pleasure of Department of Health staffers.  This allows his staff to read the Farley-esque twist on truth.  One example for now:  in October of 2010, Farley’s blog exultantly told his staff that in 2009 the department had “immunized nearly 130,000 children [against flu] in more than 1,200 schools over a few months.”  Of course, health department employees are smart — many of them knew that the 2009 H1N1 vaccine Farley was talking about was a fiasco, far too late to make a difference, and aimed at an outbreak that was more of a whimper than a bang.

What about today’s “turning point” in the obesity war?  It’s worth noting that the supposed drop in obesity among NYC schoolkids is really just a very slight (1.2%) difference in the prevalence of obesity between 2006-7 and 2010-11.

A small difference between small numbers amounts to a large percentage difference.  So the 1.2%  actual difference magically turns into the advertised 5.5% — the proportionate change.

But the false advertising gets worse

1.  The prevalence of obesity in NYC was not measured multiple times on the same group of kids (to use epidemiology jargon:  this wasn’t a panel study).  Nobody observed fat children becoming less fat.  The city simply measured obesity prevalence each year on 5- to 14-year-olds who were in the school system.  So a high proportion of the 21.9% of kids who were labeled obese in 2006-7 would have been out of the age range for the 2010-11 assessment.

Plus, lots of kids leave the NYC school system after grade school (this has to do with Bloomberg administration’s bizarre system for preventing children from attending local schools).  So, even those children who haven’t aged out of the analysis by turning 15 would be absent from the data after a few years.  And, there’s also natural immigration and emigration.

Did the 2006 fat kids get slimmer?  Nobody knows.  The 2006-7 obesity prevalence among NYC schoolkids (21.9%) can’t be compared to the 2010-11 prevalence (20.7%).  If you were forced to compare these numbers, you’d say there had been a slight change — not a 5.5% decline.  There’s the first lie.

2.  The second lie is a little more complicated.   Since there is no widely accepted functional definition for childhood obesity, children are labeled obese if their body-mass index (BMI) falls into the upper 5% of the expected distribution of weight-for-height.  This expectation is based on an old-fashioned standard.  Fair enough.  But lots of distributions shift over time — SAT scores, human height, grades awarded at Ivy League colleges, and global average temperature, to name a few.

Sometimes the reason for an overall shift of this sort isn’t hard to specify (test prep, nutritional quality, relaxation of grading standards, generalized global warming, etc.).  But the main effect causing a shift in the distribution doesn’t explain why the few people who are in the upper reaches of the distribution are so far from the mean.  To say that fewer children are now above the high-BMI cutoff than in 2006-7 therefore the tendency of children to be fat is declining is a lot like claiming that because 2011 was cooler than 2009 and 2010, global temperatures are not really going up.

(Dr. Farley, I gather that statistics aren’t your strong suit, but surely when you witnessed that snowstorm we had this past October — an outlier if there ever was one — you didn’t conclude that the climate is actually getting colder, not hotter.  So what makes you think that a very tiny decrease in the proportion of kids with high BMIs means that the city’s kids are getting slimmer?)

3.  Claiming credit.   Attributing to the health agency’s own efforts a minuscule change in the proportion of kids who are in the upper tail of the broad BMI distribution requires self-congratulation so acrobatic as to stretch credulity.

Maybe there really has been some change in the city’s children since 2006.  Or in our food supply or buying habits.  Or exercising.  But to claim that such a change both caused the tiny decline in schoolkid obesity prevalence and that it was the result of the Health Department’s efforts — the exercising and the low-fat milk and the salad bars in the school cafeterias and so forth — is to commit the fallacy that Rene Dubos outlined (in his book Mirage of Health) nearly 50 years ago:

When the tide is receding from the beach it is easy to have the illusion that one can empty the ocean by removing water with a pail.

Is childhood obesity really a health problem?

It’s not crazy for health professionals to be concerned about body mass.  Obesity might be really bad for some people, and somewhat bad for many.

But those people are adults.  Why are health agencies like NYC’s so riled up about obesity in little children?

So far, there’s no strong evidence that obesity in younger children predicts any real harm later in life, other than being a fat adult.  With adults, several signs of impending debility are more commonly found in the obese than the non-obese, such as hardening of the arteries, fatty liver, sleep apnea, and diabetes.   And with adolescents, there’s some evidence that those who are obese develop similar warning signs.  But not younger kids.

A 2005 BMJ paper reported only social effects in adulthood (being unemployed and being without a romantic partner) of early obesity.  Similarly, one cohort study carried out in Newcastle upon Tyne found little evidence that fat children became fat adults, and no evidence for predictors of illness in adulthood among those who had been overweight as children — although other studies have shown correlations between adolescent obesity and adult problems.

For kids below age 15, the most visible problem with obesity is that it occurs most commonly among the poor and dark-skinned.  This bothers the obesity warriors.  In fact, not only is obesity more common in African- and Hispanic-American children in NYC, even the slipshod standards of today’s report on NYC schoolkids can’t be manipulated to show that obesity is declining among these children.

As with all holy wars, from the Children’s Crusade through the U.S. invasion of Iraq, the warriors aren’t really concerned about principle.  Something about somebody got under their skin.

Here’s how I answer my own question:  I guess the obesity crusaders don’t like it when the children of the wealthy look like the children of the poor.  They think that white kids on the Upper East Side aren’t supposed to look like kids who live in the Bronx.

It isn’t about health, in other words.  It isn’t even about obesity.  The “childhood obesity epidemic” is about making sure society looks the way that the health crusaders want it to look.

 

 

Life Expectancy Goes Up but Risk-reduction lectures Continue

Bravo! to Rob Lyons at Spiked. Since it’s now apparent that life expectancy has increased almost everywhere and is at historic high levels in much of the developed world, Lyons asks the logical question:  why is the public health system still scolding everyone about what people eat and how fat the average person is?

A paper by David Leon in this month’s International Journal of Epidemiology showed the dramatic increase in life expectancy — the median age at death, that is.  It has reached over 85 years for women in Japan, but it’s high even in countries where longevity was relatively low a generation ago.  Cheeringly, US life expectancy at birth is now 78 years; in the UK it’s 80.  And it’s even higher in some countries of western continental Europe.  Here are the graphs for different parts of the world from Leon’s paper, showing trends since 1970:

Life expectancy since 1970

Lyons has gone after the anti-obesity crusaders before (as well as related topics at his smart blog on contemporary food confusion, Panic On A Plate).  Now, he’s particularly disturbed by the sermonizing about eating. “You can’t even have a pie and a pint without someone telling you it will kill you, it seems,” Lyons writes at Spiked.

And, really, it’s even worse than that — because it’s not just eating that’s the subject of the lecturing.  It might be true that you will live longer if you give up smoking, cut your salt intake, drop your BMI down to 24.99, exercise four times per week for at least 20 minutes each time, get immunized against flu and human papillomavirus, drink in moderation, and take naps.  But unfortunately there’s not a bit of evidence that any of that — apart from the decline in smoking — has contributed to increasing longevity.

And of course, even with smoking cessation, there’s no telling whether it would make any difference to you — only on average.

So why are the public health messages so far away from what really matters — basically, prenatal care, postnatal care, and wealth (with its concomitant, standard of living)?  Well, there’s a puzzle.

What’s the point of having an industry whose main aim is to make sure that people are constantly in fear that they are doing something that will kill them — even as it becomes apparent that most of what people do is only making us live longer?   Lyons calls it Good News Omission Mentality Syndrome (GNOMES).

I ask you:  could it have something to do with control?  And the desire to sell products?

Media Culture: Beyond Fat and Salt?

Over at Media, Culture & Health, Steven Gorelick notes that a story on salt and the food industry, which appeared on page A1 of the print NY Times on Sunday, would not have made the front page in the past.

What has changed?  How does the story of wrangling over the sodium content of American food merit space in the main news sections of the most influential media — even the front pages of the NY Times or LA Times?

1.  One answer is that health occupies much of the American conversation today.  A visitor from another planet watching our TV news shows or reading the main newspapers would have to be forgiven for thinking that Americans are dying from a multitude of irrepressible disease threats.  We can’t seem to stop talking about how to improve our health.

(In fact, as Michael Haines notes at the Economic History Association website, U.S. life expectancy almost doubled between 1850 and 1960, from 39.5 years to 70.7 years; since then it has increased slowly, and is now estimated to be about 78.2 years.  In other words, health wasn’t a matter of news much during the time when longevity was improving dramatically, in the late 19th century and first half of the 20th.  By the time health became a cultural preoccupation, the majority of Americans were living well past middle age.)

2.  Another answer, perhaps more important is that when we talk about health today we mean personal responsibility.

When I began studying epidemiology, in the late 1970s, public health essentially meant disease control.  Yes, lip service was paid to so-called health promotion — much was made of the World Health Organization’s definition of health, promulgated in 1946:

Health is a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity.

But no metric for complete well-being was widely recognized.  And the usual epidemiologic measures of incidence and mortality rates, life expectancy, and so forth seemed to work just fine as ways of understanding why some groups of people lived longer and more capable lives, while others lived miserably and died young.

Sometime since then, the health sector, including public health, has turned to individual responsibility as the key to well-being.

If each of us is responsible for his or her own health, then it’s our own fault if we get sick.  Naturally, advice abounds:  buckle up, use a condom, eat less fat, know your cholesterol level, wash your hands, use mosquito repellent containing DEET, wear sunblock, eat fresh fruit and vegetables every day, lower your stress.

The advice adds up to this:  know your limits.  Federally sponsored research tells us that self-control is ontagious.

The personal-responsibility view of health says, “control your appetites.”

3.  But let’s think about another change:  more people are concerned about the American diet.  As noted last week, the food movement has given us ways to think about eating that go beyond the tiresome story of obesity and hypertension — Beyond Fat and Salt, you could say.

Of course, the main media outlets still tell the food story in Fat-and-Salt language, as the news articles in the NY Times, LA Times, and others show.  It’s the food industry vs. the foodies, or the food industry vs. public health, or the food industry and public health vs. appetites — anyway, somebody against somebody in the name of health.

The media aren’t quite past obesity and hypertension yet.  But as the culture moves beyond obsessive self-inspection in the name of health, no doubt media will, too.