Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.

The opening words of the Institute of Medicine’s report on the potential threat posed by food ads were: “Marketing works.” Yeah, there are a large number of well-conducted randomized studies I could go through showing advertising exposure and other marketing methods can change your eating behavior and get you to eat more, but what do you need to know beyond the fact the industry spends tens of billions of dollars a year on it? To get people to drink their brown sugar water, do you think Coca-Cola would spend a penny more than they thought they had to? It’s like when my medical colleagues accept “drug lunches” from pharmaceutical representatives, and take offense that I would suggest it might affect their prescribing practices. Do they really think drug companies are in the business of giving away free money for nothing? They wouldn’t do it if it didn’t work.

To give you a sense of marketing’s insidious nature, though, let me share an interesting piece of research published in the world’s leading scientific journal: “In-store music affects product choice” documented an experiment in which either French accordion or German Bierkeller music was played on alternate days in the wine section of a grocery store. On the days the French music was playing in the background, people were three times more likely to buy French wine, and on German music days, shoppers were about three times more likely to buy German wine. Despite the dramatic effect—not just a few percent difference, but a complete three-fold reversal—when approached afterwards, the vast majority of shoppers denied the music had influence on their choice.

We all like to think we make important life decisions, like what to eat, consciously and rationally. However, if that were the case, we wouldn’t be in the midst of an obesity epidemic. Most of our day-to-day behavior does not appear to be dictated by careful, considered deliberations. Rather, we tend to make more automatic, impulsive decisions triggered by unconscious cues or habitual patterns, especially when we’re tired, stressed, or preoccupied. The unconscious part of our brain is thought to guide human behaviors as much as 95 percent of the time. This is the arena where marketing manipulations do most of their dirty work.

The part of our brain that governs conscious awareness may only be able to process about 50 bits of information per second, which is roughly equivalent to a short tweet. Our entire cognitive capacity, on the other hand, is estimated to process in excess of 10 million bits per second. Because we’re only able to purposefully process a limited amount of information at a time, if we’re distracted or otherwise unable to concentrate, our decisions can become even more impulsive. An elegant illustration of this “cognitive overload” effect was provided from an experiment involving fruit salad and chocolate cake.

Before calls could be made at a touch of a button or the sound of our voice, the seven-digit span of phone numbers was based in part on the longest sequence most people can recall on the fly. We only seem able to hold about seven chunks of information (plus or minus two) in our immediate short-term memory. Okay, so here’s the setup: randomize people to memorize either a seven-digit number or a two-digit number, to be recalled in another room down the hall. On the way, offer them the choice of a fruit salad or a piece of chocolate cake. Memorizing a two-digit number is easy, and presumably takes few cognitive resources. Under the two-digit condition, most chose the fruit salad. Faced with the same decision, most of those trying to keep the seven digits in their heads just went for the cake.

This can play out in the real world by potentiating the effect of advertising. Have people watch a TV show with commercials for unhealthy snacks, and, no surprise, they eat more unhealthy snacks (compared to those exposed to non-food ads). Or, maybe that is a surprise. We all like to think that we’re in control and not so easily manipulatable. The kicker, though, is that we may be even more susceptible the less we pay attention. Randomize people to the same two-digit or seven-digit memorization task during the show, and the snack attack effect was magnified among those who were more preoccupied. How many of us have the TV on in the background, or multi-task during commercial breaks? This research suggests that it may make us even more impressionable to the subversion of our better judgement.

There’s an irony in all this. Calls for restrictions on marketing are often resisted by invoking the banner of freedom. What does that even mean in this context, when research shows our how easily our free choices can be influenced without our conscious control? A senior policy researcher at the RAND Corporation even went as far as to suggest that given the dire health consequences of our unhealthy eating habits, insidious marketing manipulations “should be considered in the same light as the invisible carcinogens and toxins in the air and water that can poison us without our awareness.”

Please consider volunteering to help out on the site.



Please enter your comment!
Please enter your name here