At Tiny Texts we often talk about growing a business with texts, but what if SMS could be used to do something life changing—like helping kids grow up healthy? Enter Greenlight Plus, a study in which pediatricians tested whether a consistent text-messaging program could prevent obesity in the first two years of life.
With an impressive track record of engagement, this program shows how SMS can truly transform habits. And for marketers? There’s a ton to learn.
The Study Design: Personal and Persistent
Dr. Bill Heerman, a researcher and director of the Division of General Pediatrics from Vanderbilt University Medical Center, described the study design in a recent interview with JAMA Network. He said, “We enrolled families with new babies right after birth from several medical centers and 13 clinics around the country including sites in Miami and New York, Stanford, North Carolina and Tennessee.”
In Greenlight Plus, parents got seven messages every two weeks for two years. Each text was personalized, using the child’s and parent’s names, and was delivered in either English or Spanish, per the parent’s preference. These weren’t just friendly reminders—they were mini coaching sessions and celebrations wrapped into one. Here’s a peek at some of the SMS strategies:
- Frequently monitoring progress: Parents received messages like, “How many sweet drinks did Leo have yesterday?” and, “How are you doing with your goal to exclusively breastfeed?” And then the parent would respond with a numerical number from one to five or with a “Y” or an “N” to say if they had met that goal.
- Motivating through tough spots: “If they said, I had a really hard time with that goal, we would text back, ‘That’s okay, keep up the good work’. And then we would suggest a tip of how they might continue with that healthy behavior,” said Dr Heerman. Encouragement was built right in, so nobody felt guilty—just ready to try again.
- Cheering on successes: If the parent replied, ‘Yeah, I’m doing great’, we would say ‘great job, keep up the good work’, and then we’d still give them some advice after that,” said Dr. Heerman. Simple, friendly validation goes a long way.
The Results: Engagement and Retention
Dr Heerman said “The bottom line is that this intervention worked. It actually improved healthier growth trajectories over two years of life and it reduced childhood obesity.”
As for the texts, out of the 449 parents who received the text messages, over half responded to at least half the messages, and most of the families stuck with the program for the two years.
Dr. Heerman said some of his takeaways were that parents do want to hear from pediatricians and that text messages could be an effective way to do that at scale.
Marketing Takeaways: What Your Campaigns Can Borrow from Greenlight Plus
At Tiny Texts, we created a database of all the texts sent by wellness brands like ARMRA, Lemme, Sakara and Gruns, whose customers all have health outcomes on their minds. For marketers of wellness products, there is a goldmine of insight in the Greenlight Study: personalized, goal-oriented messages can keep people coming back for more, even with frequent contact.
- Make it Personal
Greenlight Plus messages weren’t just names slapped on a template. Each message used language that felt warm, familiar, and relevant, showing the power of personalization. When marketers add that same touch to SMS campaigns, it boosts engagement and makes customers feel valued. - Small Goals, Big Impact
With a focus on achievable goals, the study’s texts gently reminded parents to keep their focus. For marketers, this translates to nudging customers toward simple actions like, “Have you explored [feature]? Tap here to try it out.” Bite-sized steps help people stay engaged without feeling overwhelmed. - Encourage, Don’t Pressure
A little empathy can make a huge difference. The study’s texts provided a balance of guidance and support, especially when parents were struggling. Marketers can adopt a similar approach with support messages like, “Stuck on setting up your profile? No rush—tap here for easy tips to get going!” - Celebrate Wins
The study celebrated small victories, which made parents feel proud of their progress. Marketers can create feel-good moments by recognizing customer achievements, like reaching milestones or making repeat purchases. A quick “Great job!” text can work wonders for retention. - Don’t Be Shy with the Frequency
Greenlight Plus proved that people can stick with frequent messages if the content is valuable. For marketers, the lesson is clear: don’t hold back. If you’re providing relevant, friendly, and actionable messages, your audience will stay tuned in for the long haul. - Just The Right Amount of Info For Low Information Prospects
Dr. Eliana Perrin, Bloomberg Distinguished Professor of Primary Care, also points out that many of the study participants came from low-income households and from historically marginalized groups, thought to have low health literacy. The short format texts were crafted with health literacy principles so that parents of all backgrounds could understand and benefit.
Greenlight Plus shows that with the right mix of timing, personalization, and encouragement, text messages can move mountains (or at least, make lasting changes in people’s habits). For marketers, this case study is a reminder that SMS isn’t just a tool for updates or promos—it can be a true conversation starter that keeps customers engaged. So, the next time you’re crafting an SMS campaign, think like Greenlight Plus: keep it friendly, stay relevant, and celebrate those little wins!