J. Michael McGinnis is an IOM senior scholar and chair of the committee that looked into the issue. He told reporters at the meeting on the release of the evaluation: “There is strong evidence that television advertising of foods and beverages has a direct influence on what children choose to eat.”
And he didn’t stop there. He went on to declare: “Current food and beverage marketing practices put kids’ long-term health at risk. If America’s children and youth are to develop eating habits that help them avoid early onset of diet-related chronic diseases, they have to reduce their intake of high-calories, low-nutrient snacks, fast foods, and sweetened drinks, which make up a high proportion of the products marketed to kids.”
And the study, he claimed, supports his declaration -- about as much as the works of Moore and Dickens cited above.
We can forget the rest of the packaging the IOM put around this (eh hem) scientific study and go straight to Chapter 5.
On page 18, the last paragraph state:
“regarding the influence of televised food and beverage advertising on children’s and teens’ short term consumption, the committee concluded there was enough evidence for both younger and older children, but ‘an absence of evidence’ for teens. … For younger and older children, on balance, the evidence supported the finding that advertising influenced intake, whereas for teens, on balance, the evidence supported the finding that advertising did not influence intake. … [F]or the findings regarding advertising’s influence on usual dietary intake, there was moderate evidence for such influence for younger children (ages 2-5 years), weak evidence for such influence for older children (ages 6-11 years), and weak evidence against such influence for teens (ages 12-18 years).”
And this is what McGinnis declares is “strong evidence that television advertising … has a direct influence on what children choose to eat”? Maybe he was referring to the “strong evidence” presented on page 22 and 23. There, the report noted, “Twenty-seven of the results examined the effects of food and beverage marketing on young people’s preferences.”
The authors cite, as an example, a 2001 study by Borekowski and Robinson -- a purported smoking gun of advertising’s influence. Children shown ads in this study “preferred the advertised brand over an alternate similar product with similar packaging.”
In short, given the choice between a generic, unadvertised Costco cola and Coca-Cola, the kids would choose Coke. To which the question is: So what? Are the colas that different?
On page 5-23, the report makes a big deal out of a study by Harrison in 2005. In it, children’s beliefs about healthier food choices are measured by offering pairs of foods and beverages that (supposedly) can be substituted for each other. One is deemed healthy by researchers; the other unhealthy -- with the unhealthy one somewhat well-advertised. Only two of six showed any results: kids tended to choose fat-free ice cream over cottage cheese as being healthier, and Diet Coke over orange juice as being healthier. The fact that “fat-free” and “diet” might carry connotations beyond advertising’s influence seems to have escaped the IOM committee.
But the real glitch here is that the authors pretend to demonstrate advertising’s effect on healthy choices can be found in tables 4 and 5 in chapter 4. But these tables only show that: Coke spent $22.8 million in 2004 marketing Diet Coke; PepsiCo spent $31.9 million -- $9 million more -- marketing Tropicana Orange Juice. The Florida orange juice industry has spent billions on promotion since the days of Miss America runner-up, singer Anita Bryant sang the praises of the “Florida Sunshine Trees” and proclaimed: “A day without orange juice is a day without sunshine” in the 1960s and 1970s. So the citation is suspicious.
The report notes, also on page 23, another study that found “small, statistically significant relationships between the amount of television watched and the total number of requests for cereal and candy; relationships were not significant for fast foods and snack foods, nor for foods such as fruits and vegetables that are advertised on television.” Trial lawyers won’t like that.
Perhaps McGinnis was referring for his evidence to a section beginning on page 5-25 on the Relationships Between Television Advertising and Precursors to Diet. Here, the report says, “For younger and older children, the evidence clearly supports the finding that television advertising influences their food and beverage preferences. The number of significant results is about twice as good as it is for the non-significant results.” The total number of results reported: 28, only 11 of which had a high “causal inference.” The examples offered were of snack choices of Cub Scouts at a meeting, pairs of images of similar products, and preference for salty or non-salty food in which one of the choices was an advertised product and the other was not.
But what does this mean? Only that if a kid sees an advertised product he might want to try it. But as the report noted, in reviewing studies on requests from kids influencing parental choices when they shop: “If the product itself or the brand is not liked, then repeat purchase is unlikely.”
None of this supports the final finding by the commission that “television advertising influences children to prefer and request high-calorie and low-nutrient foods and beverages.” Again, it supports the conclusion, instead, that a child choosing between a Coca-Cola and a Costco cola will have a preference for the Coke.
But let’s look further, at studies described on page 5-32 in support of this strong influence.
Here, the report provides two examples of advertising influence. A 1980 study by Galst over a four-week period allowed children ages 3-6 to select a snack, and researchers recorded their choices. Some of the kids were shown commercials for sugared snacks, some for fruit and milk, some nothing at all. Some were told by a graduate student sugary snacks were bad, others weren’t. Result: “Children in all five groups selected sugared snacks the majority of the time, and the groups were not statistically distinguishable.”
A 1983 study by Bolton had parents and kids keep diaries of television exposure from which they calculated exposure to advertising and diet. It found “exposure to television advertising was associated with an increased number of snacks, but … variations in parental snacking … explained much more of the variation in the children’s snacking behavior than did variations in television advertising exposure.”
Parents’ behavior matters. Maybe we should ban advertising to them.
Studies on the Influence of Television Advertising on Usual Dietary Intake (page 5-34) produced these results, according to the report: “Among the results with high causal inference validity, none showed a significant effect and two showed no effect.” Seven of eight with medium ability to infer causation found a significant effect.
The one study rated highest for causal inference was by Robinson in 1999. It reduced television watching for one group of young children over another and found a significant effect on reducing Body Mass Index. Only the reduced TV group didn’t lower their BMIs by a shift in consumption. Indeed, “their consumption of highly advertised foods and beverages was indistinguishable from that of the untreated control groups.” Sort of cuts the IOM’s link between food advertising and childhood obesity, one would think.
Interestingly, McGinnis makes much of fast food promotion being inextricably linked to increased obesity. On this point, the report notes on page 5-38 a 2001 study by French (et al.) which found “the television viewing measure was associated with fast food consumption, which the committee counted as a significant effect, but they also found that fast food consumption among teens was independent of BMI.” In other words, obese and overweight people and normal weight ones eat much the same things at Burger King.
Nevertheless, the report finds “moderate evidence that television advertising influences the usual dietary intake of younger children ages 2-5 years and weak evidence that it influences the usual dietary intake of older children ages 6-11 years.”
And McGinnis translates this into “strong evidence” that “[c]urrent food and beverage marketing practices put kids’ long-term health at risk.”
Oh, give us some figgy pudding -- and a big cup of good cheer… We need it if we’re expected to swallow studies like this.
Last edited by DuaneFreese : 12-16-2005 at 07:18 AM.