Hair care brands Living Proof and Alterna are already reaping the benefits of signing celebs to endorse their products, even before ads have hit magazines, signaling the power of word of mouth and social media on such collaborations.

Sephora’s Priya Venkatesh, Vice President, Divisional Merchandise Manager Skincare, said, “We have seen a marked uptick in Living Proof’s business since the Jennifer Aniston announcement. We believe this is due to both the celebrity announcement and the launch of Prime,” a new item that is formulated to extend the life of a hairstyle.

When Living Proof announced in October 2012 that it had signed Jennifer Aniston as not only the face of its hair care brand but also a part owner of the company, the beauty industry couldn’t help but deliver a reverberating “Kudos!” to the Cambridge, Mass.-based firm for landing arguably the most sought after celeb beauty had yet to snare.

“Living Proof is a brand that has always leveraged a unique alchemy of talent: unique scientists, incredible creative talent and stylists, great marketing. But we were missing the Hollywood connection. Who has better hair than Jennifer Aniston?” said Jill Beraud, Chief Executive Officer of Living Proof.

Jill described Jennifer as having “the most famous hair in the world” but also much more than that. “She is a very savvy business woman who has been approached by many other beauty companies. She loves to help growing companies and what attracted her to Living Proof initially was the science behind the innovation. What ended up convincing her were the products.”

While the ads featuring Jennifer are just now appearing on newsstands, Jill said the company saw a spike in sales in the days following the announcement of the partnership.

“She’s already impacting the business. Having this major hair icon love your products has helped us get brand awareness. We have a very loyal—but—small following. The biggest opportunity was brand awareness, which was very low, especially on a global level.”

Currently, Living Proof is sold in QVC, Sephora, Nordstrom and Ulta in the U.S., as well as in salons. Presence in salons looks to grow throughout 2013; U.S. retail distribution will remain constant. Outside the U.S. Living Proof is sold in Space NK and Mecca stores, but that will look to expand as the company leverages Jennifer Aniston’s global recognition and admiration. This week Living Proof announced the closing of a $30 million financing that will accelerate market expansion and support the development and commercialization of additional beauty technologies. The financing was supported by new institutional investors including Leerink Swann, and joined by existing investor and company founder Polaris Partners, as well as the Pohlad Family Capital Fund.

Alterna is equally seeing increased sales results, generated from its January announcement of partnering with Katie Holmes for its hair care brand, as well as for naming her a part owner of the company.

“We have had tweets all over the world in countries we are not even selling in, especially in Japan. Virtually [the brand and Katie] are being tweeted about everywhere,” said Joan Malloy, Chief Executive Officer of Alterna.

Alterna’s salon partners have reported “high double digit sales increases” since the announcement, Joan said. Sephora reported that sales almost doubled the week of the first press mention, with sales climbing 92 percent, while Sephora.com saw sales double in January, up 115 percent year over year. Ulta saw sales saw a lift of 111 percent year over year the week after the announcement, according to Alterna, while Nordstrom.com sold out of key sku’s the week after the first press mention. Year-to-date, Alterna has realized more than 500 million media impressions. Compare that with the company’s annual media impressions in all of 2012, which were 600 million.

“For our brand it’s news and it’s newsworthy. How this will translate into retail will be seen in the next couple of months after the ads hit and we can see sell through. But there is a lot of upside.”

Alterna is in “The Year of Transformation.” The company recently moved to Midtown from Los Angeles for a host of reasons, including to be closer to the beauty industry’s top talent, their PR agency [Lippe Taylor] and beauty editors. Not to mention, being in a more European-friendly time zone.

“Try having a conversation with Russia from Los Angeles. You have to be on the phone at 5:30 in the morning.”