The findings come as part of a Thompson Reuters Pulse Healthcare Survey, which collects information about health behaviour, attitudes and product use from over 100,000 US households.
Conducted in the first two weeks of June 2010, the survey found that nearly 60 percent of participants believe that advertising for dietary supplements is untrustworthy.
Advertising reach
Out of the 3,013 participants in the telephone survey, around 63 percent said they had seen, heard or received advertising for nutritional or dietary supplements over the past six months.
Overall, 77 percent of adults earning more than $100,000 said they had been exposed to advertising for these products during the period. This compares to 51 percent of people earning less than $25,000.
A similar trend was noted according to the level of education of respondents: 47 percent of people with high school education or less said they had seen supplement ads in the past six months, compared to 70 percent of those with college degrees.
Influence from advertising
However, despite relatively high levels of exposure to supplement marketing, only 11.5 percent of those who had seen ads said they were influenced by these to purchase the product.
Those who were most influenced were the lower income bracket (18 percent of people earning under $25,000 compared to 9 percent of those earning over $100,000). Younger consumers were also more likely to purchase advertised supplement products (16 percent of people under 35, compared to 10 percent of 35-64 year-olds and 8 percent of over 65 year-olds).
Not trustworthy
Participants were also asked how trustworthy they found claims made by dietary supplement manufacturers.
Overall, almost 60 percent of people said they did not find these to be trustworthy, compared to 10 percent who trusted the claims.
Thompson Reuters said the margin of error of its survey findings is 1.8 percent.
Fixing a bad reputation
The supplement industry trade group Council for Responsible Nutrition (CRN) said that all product advertising results in a certain level of consumer skepticism, but that supplements also suffer from the irresponsible advertising of certain 'rogue' players.
“People in general would say they don’t trust advertising—and that isn’t specific to the supplement industry. But regarding this study, consumers’ distrust of supplement ads can likely in part be attributed to egregious and far reaching claims made by irresponsible companies who are exaggerating the science to sell their products. Unfortunately it’s the actions of a few bad players that can take its toll on the entire industry," said Erin Hlasney CRN senior director of Communications.
"CRN will continue to encourage companies to take a close look at their advertising claims to ensure they are based in sound science, and to remind consumers that if something sounds too good to be true, it likely is. This will help increase the trust factor and reinforce that the vast majority of the supplement industry puts the health of its consumers first.”