Direct selling cosmetics firms such as Avon and Oriflame have successfully relied on the recommendations of friends and family to sell their products for many years.
A new global survey of 26,486 internet users conducted by AC Neilson indicates that 78 percent of customers trusted recommendations from other customers while only 26 percent trusted online banner adverts.
Traditional advertising in newspapers and on television fared markedly better with more than half of respondents putting their trust in these forms of marketing.
The survey also revealed several national variations with Asians respondents being most likely to respond positively to recommendations while consumers in Western societies were least likely to trust any form of advertising.
"Building trust is a major issue in marketing these days with most consumers taking product claims in traditional advertising with a pinch of salt," said Alan Wilson, the head of the marketing department at Strathclyde University.
He added: "In theory people trust word of mouth recommendations but people rarely talk to their friends about the products that they use, which limits its effectiveness in practice."
Marketing professionals have responded to the problem by employing strategies to increase word of mouth recommendations and gain the trust of beauty consumers in cynical developed markets.
Last year, Proctor and Gamble (P&G) launched a word of mouth marketing venture called Vocalpoint with the aim of multiplying positive recommendations.
Housewives were given exclusive access to cosmetics so long as they gave feedback and spread the word about the products to friends.
Marketing expert Wilson said other strategies for overcoming trust issues involve the use of 'pseudo friends' via celebrity endorsements and media coverage.
In order to improve their media coverage many companies are accompanying information on product releases with newsworthy research such as surveys.
For example, Philips Sonicare accompanied the launch of a UV Sanitizer for toothbrushes this week with the results of a survey suggesting that Americans have poor oral hygiene habits.
However, Wilson said genuinely independent media coverage is the most effective means of increasing sales but marketing professionals have little influence over such coverage.
Earlier this year sales of the Boots No.7 anti-wrinkle serum increased 2000 percent after it was shown to be more effective than expensive rivals in TV science documentary, the BBC's Horizon program.