Like many top online retailers, multichannel vitamins and supplements retailer The Vitamin Shoppe has run triggered email campaigns for years. Those go out automatically to individual consumers reminding them about specific items they had browsed on VitaminShoppe.com or added to their cart, but never opted to purchase.

A mass email from The Vitamin Shoppe is personalized to each customer with four products recommended based on prior on-site behavior.

Still, the vast majority of its daily email campaigns are so-called “batch-and-blast” messages sent to its full email list, aimed at announcing a sale or new product launch. Until last year, in these daily, scheduled email campaigns, Vitamin Shoppe had no way of showing products to each customer based on what they had already searched for on Vitamin Shoppe’s website, or had in some other way expressed interest in.

To change this, the retailer solicited personalized email marketing firm Movable Ink about eight months ago to generate mass messages tailored to buying or browsing behavior it had on its customers. To use the service, Vitamin Shoppe still sent one campaign, but the email was automatically personalized to thousands of recipients based on the types of products they had either bought, searched for or added to their cart in the past.

For example, in one test, Vitamin Shoppe ran an email campaign celebrating its 40-year anniversary, but also offered a “Buy one, get one 50% off” deal and “$10 birthday cash.” But a bar in the middle of that email displayed four products—each personalized to what customers had browsed but never purchased before—with the headline: “We saved these just for you.”

That email with personalized product recommendations, tested against the same message but with a set of predetermined products not personalized based on each customer’s search history, showed strong results: a 271% lift in click-through rate and an 8% lift in revenue.

Making use of data it has on what consumers search for on its site was especially helpful for Vitamin Shoppe, as 65% of consumers that visit VitaminShoppe.com use the site search box, says Brandon Farraye, director of CRM & retention at Vitamin Shoppe. “This was a huge win for us to dynamically populate product imagery based on what the consumer has searched for. Our communications are a lot more relevant now.”

Vitamin Shoppe also has used Movable Ink’s product recommendations technology to show consumers via email other items similar to those they’ve already purchased or browsed. And it promotes in-store shopping with a feature that shows consumers a map with the location of the store closest to her when she opens her email.

Neither company would comment on the cost of the technology, but Movable Ink says it is designed for mid-market and enterprise companies. Pricing varies based on the number of emails opened and services purchased.

The Vitamin Shoppe is ranked No. 234 in the Internet Retailer 2017 Top 1000.