Tuesday, July 28, 2009

Nutrition Information Only For the Obsessed?

Contra Megan McArdle, I don't think a person must be prone to "obsessing about the calorie content in [their] food" for nutrition information supplied at restaurant point-of-purchase to have some effect on what they order.

We've seen that people underestimate the calorie content of restaurant foods, by as much as 55%. (McMann 2004). And research has shown that people underestimate the calorie and fat content more drastically for the largest restaurant meals than the smallest ones:

* Kozup, Creyer and Burton (2003) discovered that giving nutrition information in a menu context has a greater influence on purchase intention than on a packaged food product, perhaps because consumers are less aware of the nutritional profile of restaurant foods.

* Burton et al. (2006) provide additional evidence for consumers’ tendency to underestimate the calorie and fat values of restaurant items; “less healthy” entrees averaging 1336 calories were reported by consumers to contain an average of 642 calories (48% of the real value), and entrees averaging 76 fat grams were estimated to have 32 g (42% of the real value). Consumers did much better with healthier items, estimating calories at 92% of their real value (500 vs. 543) and fat grams at 65% of their real value (8 vs. 15).

* In a mail survey associated with this study, participants looked at one of four individual menu items with full nutrition information, calories only, or no information; purchase intent and choice for the “less healthy” items was reduced when given nutrition data, as these options were even worse than participants had expected.

* These results support prior work finding that the presentation of accurate but unfavorable nutrition information on a mock menu leads consumers to rate the food as unhealthier, the negative health consequences of eating the food higher, and purchase intention lower than when no information is given (Burton and Creyer 2004).

So it's those people who are looking to eat something moderately indulgent who suffer the most from the lack of information because they can so easily end up with a meal that is much more insanely unhealthy than they want and never know the difference. I would expect most people, no matter how blase they may seem about their eating, do have a point at which they would look at a menu and say, "Holy crap, that's a lot of calories and fat!" I suspect that restaurant food crosses that line more often than people know.

The post and comments make for interesting reading. You can see my comment (which is mostly a response to other commenters) posted as Sally, July 28, 2009, 4:19 PM. This is the first time I have bothered registering to comment on that site, but I was just overcome with this feeling that "someone is being stupid on the Internet!" and had to offer some data to the wild speculation going on.

7 comments:

Tam said...
This comment has been removed by the author.
Tam said...

All right, let's try this again with fewer typos:

Wow, I think McArdle is really wrong on a lot of counts here.

1. "We've required nutritional labelling on food in the supermarket for decades, and this has not exerted any noticeable downward pressure on America's waistlines..."

We don't really know this, do we? I grant that Americans have gotten fatter, not slimmer, but that doesn't mean they wouldn't have gotten even fatter without the labeling.

2. "If you skip the donut, you'll eat four apples or an extra slice of bread with dinner."

I've heard of plenty of people eating a donut, but rarely have I heard of someone compulsively eating four apples. I am under the strong impression that it's been empirically demonstrated that people do not simply eat the same amount of calories regardless of their food choices.

3. "Moreover, I bet that after Macaroni Grill reformulates its scallop and spinach salad, more people start ordering heavier entrees, because they suddenly notice that they're still hungry after they eat the salad."

I'm sure this is true in some cases. But I know that I personally am often satisfied after eating, for instance, a 600-calorie meal. So if I ordered, ate, and enjoyed such a meal, I wouldn't be dissuaded from ordering it again in the future just because I was more peckish at the next mealtime. I'd also happily eat 1200 or probably even 2000 calories. So, yes, if I order something that is only 300 calories I probably won't be very satisfied, but there are a lot of calories that can be cut before I reach that "not satisfied" level.

mom said...

A book I read several years ago reported on a restaurant that decided to be responsible about nutrition labeling and posted their menu with nutrition info where patrons could make a decision before they order. What they found out was that people didn't want to eat food with so much fat, calories, etc., so they left to eat somewhere else (where the food was equally not nutritious). They quickly took the menu with the info down so that their patrons could feel okay about eating there again.

Jen M. said...

Adding to Tam's comment on #2 -- ummm, wouldn't anyone agree that you're healthier eating 4 apples or an extra slice of bread than a donut?? Last time we ate out at a Mexican restaurant, they had calories listed and I couldn't believe (well, I could) that there was nothing under 1000 calories on the menu. The only way to know what you're really eating is to cook at home.

Sally said...

(1) Research on supermarket product sales just before and after the NLEA required nutrition labels has suggested that after labeling was established, consumers purchased more low-fat items at the expense of low-calorie items or products with higher nutrient values (e.g. vitamins).

This makes sense, given that the NLEA occurred in 1990, when "eat a low fat diet" was the dominant prescription for healthy eating and weight loss. So the fact that the NLEA has not exerted "noticeable downward pressure" on weight may be due in part to the fact that people were looking for weight loss in all the wrong places.

And I agree with Tam that we cannot know the effect of the NLEA by looking at population weight change, since we don't know what the secular trend absent the NLEA might have been.

(2) Yeah, the four apple thing was very silly. And Jen is right - if only Americans had the problem of wanting to eat a bunch of apples in the evening, we'd be a lot healthier.

(3) The funny thing about the salad reformulation is that while 390 calories is not as little as most people would want to eat for dinner, who goes to the Macaroni Grill and doesn't eat some of the (free!) sourdough bread and olive oil? 390 + bread + oil = plenty to eat. Some people might be relieved to finish their meal and not be super-stuffed. And if they get hungry later and want to eat 4 apples, good for them. It's not necessary to treat every meal as the last food you will ever eat. Unfortunately, we live in a culture that too easily equates being really full with having a satisfying and satisfactory meal.

* Mom, yeah, the fact that restaurants have tried the full disclosure of nutrition data then reverted back to their mysterious ways suggests that the food is higher calorie than people think and are willing to eat. (I think of this as being too "costly" in calorie terms for what I'm getting.)

I've been surprised the extent to which people act like it's only the calorie content of the food that matters in determining satiety. I have read that people tend to gravitate toward eating a given amount (mass) of food per day, not necessarily a given number of calories. Thus the effectiveness of a diet that encourages you to eat high volume food rather than calorie-dense food.

Sally said...

Duh, I meant to write that 390 calories is not as MUCH as most people would want to eat at dinner.

Tam said...

And yeah, I agree that 390 calories plus bread and oil is enough calories for most women, at least, for dinner.