Thursday, April 09, 2009

The 'Joy' of Misinformation

The mainstream media like to depict obesity, and too often make the mistaken claim that obesity shares a causal relationship with type 2 diabetes (the most common form), even though the validated scientific evidence on that is anything but conclusive. At best, there is a correlation, but as anyone who works with statistics can tell you (including me and my work with marketing research), it's a very big mistake to say that obesity causes the disease (see here for some critique of the routine confusion between these terms). Obesity is certainly not healthy, but it annoys me when the media routinely state things as facts when they aren't facts.

Correlation does not equal cause.

Too often, the media concludes a causal relationship among correlated observances when causality was not even considered by the study itself. Without clear reasons to accept causality, we should only accept correlation. Two events occurring in close proximity does not imply that one caused the other, even if it seems to makes perfect sense.

Anyway, statistics aside, the other day, Jenny Ruhl (Diabetes Update Blog) featured an interesting post about how the rise in toddler obesity pointed to genetic damage from pollutants. I am inclined to agree with her thesis. Indeed, I agree with her, but the larger obesity issue is often oversimplified to be the cause of type 2 diabetes and it isn't. Her posting made me think about the larger obesity problem and how the popular press seem to imply causal relationships where they don't exist.

High fructose corn syrup, a product of genetic engineering, overproduction of a crop the world doesn't really need more of, and let's not forget chemical production, may also contribute, but is it THE reason? Highly unlikely. There are many factors at work, and we can certainly point to changes in the American diet as another factor. Again, the mainstream press like to claim that junk food is the cause of this problem. While higher consumption of higher-calorie foods found at fast-food establishments can lead to obesity, even in the poorest neighborhoods, few residents eat every meal at the Golden Arches, even if it IS the only restaurant around.


A few months ago, the Los Angeles Times had a very interesting article entitled 'The Joy of Obesity' in which researchers examined the classic American cookbook and the most recent edition. Their finding:

In the classic American cookbook, which has been published since 1931, changes in ingredients and serving sizes have led to a 63% increase in calories per serving in many recipes featured in the book, according to a fairly recent study.

There are many reasons for the increase in the nation's obesity, and it may even deserve to be called an epidemic. But the press isn't doing us any favors by claiming some things as fact, when they aren't. If we are to have an honest discussion about how to address the nation's healthcare problems, our citizens cannot be relying on inaccurate information.

It's that simple.

Joy of Cooking' or 'Joy of Obesity'?
By Jeannine Stein, Los Angeles Times
February 17, 2009

Restaurants get a bad rap for serving gargantuan portions of food and contributing to Americans' expanding waistlines. But what if something in your home were equally guilty? Something as innocent as ... "Joy of Cooking"?

The classic "cookbook, first published in 1931, has done some girth-expanding of its own, a new study has found.

Published as a letter Tuesday in the Annals of Internal Medicine, the report examined 18 classic recipes found in seven editions of the book from 1936 to 2006. It found that calorie counts for 14 of the recipes have ballooned by an average of 928 calories, or 44%, per recipe. And serving sizes have grown as well.

Take beef stroganoff: In the 1997 edition, the recipe called for three tablespoons of sour cream. The 2006 edition calls for one cup.

Then there's waffles: In 1997, the basic recipe made 12 six-inch waffles; in 2006, the same ingredients made about six waffles.

Overall, the scientists found, changes in ingredients and serving sizes led to a 63% increase in calories per serving in 17 of the recipes between 1936 and 2006.

"When we talk about obesity, people like to plant the source of the issue on away-from-home dining," said Brian Wansink, the study's co-author and director of Cornell University's Food and Brand Lab. "But that raised the thought in my mind: Is that really the source of things?. ... What has happened in what we've been doing in our own homes over the years?"

Wansink and co-author Collin Payne, assistant professor of marketing at New Mexico State University in Las Cruces, said they wanted to quantify how home cooking had changed, but knew that doing it anecdotally wasn't scientific. So they turned to cookbooks, settling on "Joy of Cooking" because of its history and the fact that it had enough recipes carried through all editions.

In addition to beef stroganoff and waffles, recipes chosen for analysis included macaroni and cheese, goulash, Spanish rice, brownies, sugar cookies and apple pie.

Wansink said similar calorie increases were found in other enduring recipe books such as the "Better Homes and Gardens Cook Book."

The study found that some of the added calories in the dishes came from a substitution of ingredients -- extra meat instead of vegetables, for example. Back in the day, meat was expensive, so less of it was used, he said.


In other recipes, Wansink said, sauces were added, or more butter or sugar, or extras such as nuts and raisins. "They're now there for a little more excitement," he said.

Cultural shifts may have also had an effect on recipe ingredients and portion sizes, Wansink added. Families have gotten smaller, so a dish that once was consumed by eight people is now consumed by four.

And because sizes of dinner plates have grown over the years, a standard 2-ounce portion of pasta can now look diminutive.


Jeannie Gazzaniga-Moloo, a Roseville, Calif.-based registered dietitian and spokesperson for the American Dietetic Assn., said she was surprised by the findings.

"I would have expected that with the increasing awareness of nutrition, the calories would have been lower or stayed the same," she said.

Beth Wareham, editor of the 2006 edition, is not losing sleep over the study.

"It's such a tiny number of recipes. It's really a non-event," she said.

She said that the book has become more healthful overall, booting out many processed foods in favor of fresh ingredients. The 2006 edition has a chapter on nutrition written by Dr. Walter Willett, chairman of the nutrition department at the Harvard School of Public Health.

In putting together the latest edition, writers and recipe-testers used their common sense in terms of ingredients and serving sizes, Wareham said -- and they figured readers have some common sense of their own.

"We give Americans credit," she added, "for knowing that eating a brownie is not as good as eating a plate of whole grains and vegetables."

jeannine.stein@latimes.com

URL for this article:
http://www.latimes.com/news/science/la-sci-joy17-2009feb17,0,320694.story

2 comments:

Jenny said...

Scott,

I am sure portion size is a huge issue for adults and teens. But the point I brought up in my blog post is that healthy toddlers are not yet subjected to these cultural influences and if they have healthy regulatory systems they are very difficult to overfeed.

I had one child who was an underweight toddler and learned first hand how difficult it can be to make a 2 or 3 year old eat if they don't want to.

It is only when children reach school age that the cultural factors start to kick in. Which is why obese four year olds are such a concern. To be obese at age four a child must have been overeating a one, two, and three. And all the research from the 50s-70s suggests this won't happen in a normal child.

Scott said...

Jenny,

As always, I appreciate your thoughtful comments. First, I hope I did not imply that your posting was misinformation; that wasn't my point at all. As I noted, I am inclined to agree with your sentiments on childhood obesity. In fact, your posting made me think more closely about about these issues as well as all of the common thoughts about what is behind the larger issue of obesity.

There are a variety of factors behind the nation's obesity problem (which is not limited to children), but that the popular press seem to imply causal relationships where there are merely correlations.

I appreciate your clarifications and hope that I did not misrepresent my thoughts in any way.