For decades, health advocates have pushed for aggressive warning labels to alert consumers of the risk of items such as cigarettes and medications. But new research suggests that warning labels can actually have the opposite effect.
The new study suggest that when there is a time lag between reading a warning and then buying, consuming, or evaluating the associated products, the warnings may encourage trust in the manufacturers of potentially dangerous products, making them less threatening.
The study by Yael Steinhart, Ph.D., of Tel Aviv University, along with Drs. Ziv Carmon of INSEAD in Singapore and Yaacov Trope of New York University, is published in the journal Psychological Science.
Experts believe the study findings could help improve the efficacy of warning labels.
“We showed that warnings may immediately increase concern and decrease consumption,” said Steinhart.
“But over time, they paradoxically promote trust in a product and consequently lead to more positive product evaluation and more actual purchases.”
The study is based on an idea called “the construal-level theory” (CLT). The theory posits that when thinking about objects over a period of time, people tend to construe them abstractly, emphasizing what they describe as “high-level features” and suppressing “low-level features.”
The high-level feature of warning labels is that they build trust in consumers by creating the impression that all the relevant information about the products is being presented.
The low-level feature of warning labels is that they make consumers more aware of the products’ negative side effects.
The CLT holds that over long periods of time, consumers de-emphasize side effects and emphasize the feeling of trust communicated by warnings over time.
Ironically, this may increase the purchase, consumption, and assessment of the associated products.
To test this prediction, the researchers ran a series of experiments. In one experiment, they showed smokers one of two ads for an unfamiliar brand of cigarettes, either with or without a health warning.
When smokers were told the cigarettes would arrive the next day, the warning worked — decreasing the number of cigarettes purchased by an average of 75 percent compared to a group that was not shown the warning.
But when smokers were told the cigarettes would arrive in three months, the warning backfired — the number of cigarettes purchased increased by an average of 493 percent compared to a group that was not shown the warning.
In another experiment, the researchers showed women ads for an artificial sweetener, again either with or without a health warning.
When women were given the chance to order the sweetener right away, the warning worked — decreasing the packages of sweetener ordered by an average of 94 percent compared to a group that was not shown the warning.
But when women were given the chance to order the sweetener just two weeks later, purchases increased by 265 percent compared to a group that was not shown the warning.
Those who want to minimize the deterrent effects of warnings would be better off building in a delay of some sort than burying the warnings in fine print, the researchers say. But those who genuinely want to inform customers of risks should ensure warnings are seen, or repeated, shortly before products are bought or consumed.