Last week, Brafton reported that email marketing has been proven to produce tangible results. Now, a new investigation from Business 2 Community Marketing Insider reveals that email campaigns will keep delivering returns as long as the content offered to subscribers is fresh and relevant.

B2C executives measured the results of an email campaign over the course of six weeks. They aimed to re-engage old leads using fresh content in weekly messages, and the results reveal that new content brings new life to email outreach. The company reconverted 40 leads in six weeks.

The investigation proved that email open rates did not lessen over the course of the six-week period. Open rates in weeks five and six were comparable to those in week one. Instead, it seems open rates are closely linked to headline and body content.

B2C says that direct, informative subject lines performed up to 20 percent better than sales-oriented headlines. The company also found that case studies are compelling email content, and consumers were willing to click to links to videos published on corporate websites.

The bottom line, according to B2C, is that brands need more content. “In six weeks, we generated [more than] $100,000 in return merely by sending content-packed emails to our list of 'cold leads,'” says David Huffman, a B2C Marketing Insider contributor.

Marketers may take this as a cue that they should invest in content for email campaigns. Brands should also invest in ensuring their content is mobile-ready; as Brafton has reported, more than 70 million consumers now check their inboxes on the go.