People who follow brands on Twitter say they are more likely to buy products from the brands they follow and more likely to recommend those brands to friends, according to a new study by Constant Contact and Chadwick Martin Bailey.

Among surveyed Twitter users who follow at least one brand on Twitter, fully one-half (50%) say they are more likely to buy products from brands they follow on Twitter. Interestingly, male brand followers are more likely than their female counterparts to buy a brand's products after following it on Twitter, 55% vs. 45%.

Below, additional findings from a survey of Twitter users in the US from Constant Contact and Chadwick Martin Bailey, which explores how Twitter users who follow brands interact with those brands.

Recommending Brands to Friends

Following brands on Twitter motivates people to recommend those brands: Fully six in ten brand followers say they are likely to recommend a few (42%) or many (18%) brands to friends after following them on Twitter.

Older brand followers (age 35-49) are less likely to recommend a few (14%) or many (33%) brands to friends after following them on Twitter.

Being the First to Know

Most (64%) Twitter users who follow brands say they do so because they are already a customer, but early access to information is key for many Twitter followers: 61% follow brands in order to be the first to receive information about the brand, while 48% are motivated by discounts and promotions.

Roughly one-third of brand followers want the inside scoop: 36% follow brands to gain access to exclusive content.

Followers Tend to Stay With Brands

Only 13% of brand followers say they have "un-followed" a brand, whereas 75% have never done so with fans over age 35 the most likely to remain a brand follower, according to the study.

Brand Followers Are Few, Selective

Only 21% of surveyed Twitter users say they follow brands on Twitter. Moreover, such followers are selective about the brands they do follow on Twitter: 79% follow fewer than 10 brands.

Younger Twitter users are more likely to follow brands on Twitter: 26% of those under age 35 do, compared with 17% of those age 35-49, and 13% of those age 50+.

Twitter Still Gaining Momentum

Brand followers are becoming more active with brands on Twitter: 33% of such followers report interacting with brands more this year than they did last year, whereas 57% are interacting at the same level. Men are increasing their rate of brand interaction more than women, 38% vs. 27%.

In addition, nearly half (47%) of Twitter users have been tweeting less than one year.

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Other key findings: 

• Twitter users are active Internet users overall: 50% go online more than once an hour.
• Brand followers read brand posts more than they tweet about brands: 84% read tweets posted by brands, whereas 23% tweet about the brand. 

About the data: Findings are from a survey of 1,491 US consumers ages 18 and older, conduct via the Research Now online panel by Chadwick Martin Bailey with Constant Contact, January 2011.