Hundred Health and BellSant Become One to Make Precision Health Personal, Proactive, and Always On

Before Tyler Smith founded Hundred Health, he was leading SkySlope, a real estate software firm he built and later sold a majority stake in to Fidelity. Despite his success, Smith found himself confronting a more personal question: how well was he aging?

“I was turning 39, and my wife and I were having our first child a little bit later in life,” Smith said in an interview. “I began thinking about life a little differently, like, how old is my child when they’re driving? And how old is my daughter going to be when she’s graduating?”

Prompted by that reflection, Smith took a biological age test. Though he exercised regularly and maintained a healthy diet, the results were unexpected—his biological age came back at 47.

“I had more data on my businesses—arguably even on my car—than I did on my own body,” he said. “That was kind of like a big wake-up call.”

Smith responded by hiring a team of longevity specialists and undergoing a full suite of diagnostics from blood biomarkers and wearables to genetic testing and full-body MRIs. A year later, he had reduced his biological age to the early 30s. That experience eventually led him to build Hundred Health, a platform designed to make high-fidelity health tracking and individualized insights available to a broader population for under $1.50 a day.

Now, with its acquisition of longevity platform BellSant, Hundred Health is expanding its capabilities with a substantial injection of scientific depth. In an exclusive interview with AIM Research, Tyler Smith talks to us about why this collaboration was necessary. The all-stock deal gives Hundred access to BellSant’s proprietary datasets, spanning aging, genomics, metabolic biology, sleep science, and cognitive health developed by more than 25 researchers from Johns Hopkins, Harvard, Columbia, and Stanford.

“Matt and the BellSant team have assembled one of the world’s richest longevity datasets,” said Smith. “By folding their science directly into our platform, every member will have on-demand access to the collective expertise of dozens of leading researchers to inform smarter, personalized health decisions.”

The integration will strengthen several core features of the Hundred platform, including peer-based comparisons, dynamic reference ranges, and longitudinal health tracking. BellSant’s models include optimal biomarker ranges, hazard-ratio functions, and demographic personalization logic, allowing Hundred to deliver more context-aware insights.

“We’ll begin by ingesting BellSant’s optimal biomarker ranges and hazard‐ratio functions into our existing data, ensuring seamless alignment,” Smith said. “Layered on top of this, BellSant’s demographic personalization logic—accounting for factors like age, sex, genetics, and lifestyle—will enable us to generate truly individualized reference ranges, so that recommendations are contextually tailored. For example, a 45‑year‑old endurance athlete receives different thresholds than a 65‑year‑old office worker.”

Smith noted that the platform’s AI engine takes raw health inputs and transforms them into narrative insights that guide users step by step. “Our AI engine takes the raw data across blood, genetic, and wearable data and distills it into clear insights that guide users step by step,” he said. “Behind the scenes, natural‑language synthesis algorithms parse BellSant’s hazard‑ratio models and our longitudinal trends to identify what’s working—for example, ‘Your inflammatory markers have improved 15% since last panel, likely due to your Mediterranean‑style diet’ and where to focus next, like, ‘Let’s boost your HDL by adding a 10‑minute brisk walk each morning.’”

Each recommendation is presented in an action-oriented narrative structure—“Here’s your win,” “Here’s your next priority,” and “Here’s exactly how to do it.” Users who want additional context can access plain-language explainers or links to primary research.

Matt Fellowes, who founded BellSant, will join Hundred’s advisory board. Select members of his team will also transition to Hundred to help integrate the two systems and accelerate the product roadmap. “Choosing a future for BellSant’s platform wasn’t a decision we made lightly,” said Fellowes. “After careful evaluation, it was clear that Hundred represented not just the right home but the right future. Tyler and his team aren’t just building technology—they’re building a fundamentally better model of healthcare. One that is intelligent, personal, and empowering. I couldn’t imagine a better partner to carry this mission forward.”

One of the near-term outcomes of the acquisition is the ability to generate earlier warnings and more precise recommendations based on biomarker trends. “We’ll be able to surface early‑warning alerts when users’ longitudinal biomarker trends cross risk thresholds, months or even years before conventional diagnostics would catch them,” Smith said.

Hundred plans to expand into AI-guided coaching, drawing on BellSant’s models to simulate the role of a longevity expert. “This predictive capability paves the way for precision interventions: AI‑driven ‘smart protocols’ that recommend tailored adjustments in nutrition, exercise, and sleep based on each individual’s evolving profile and risk factors,” Smith added.

Hundred also emphasizes accessibility. “For Hundred, accessibility means breaking down every barrier, financial, technological, and educational that has traditionally kept longevity care in the hands of the few,” said Smith. The platform is designed to support a wide range of wearable devices, including entry-level fitness trackers, and presents insights in language designed to be easy to understand regardless of background.

“We’ve democratized access, offering elite‑level longevity science for under $1.50 per day, so that industry-leading personalized health insights are no longer limited to the wealthy few but available to anyone committed to living their healthiest life,” Smith said.

Where many longevity tools emphasize performance metrics or generic scores, Smith said Hundred’s approach is different. “Hundred stands apart first in the depth of our data: we deliver twice‑annual comprehensive panels covering 115 biomarkers, genetic analysis, and wearable integration,” he said. “Most others on the market offer a fraction of the blood data, no genetic or wearable for the same price.”

“Second, we incorporate proprietary, peer‑reviewed science—BellSant’s optimal ranges and hazard‑ratio models are built directly into our AI engine, so every recommendation is evidence‑backed and transparent.”

The name “Hundred,” Smith explained, is meant to be a digestible goal—not abstract or extreme. It stands in contrast to figures in the longevity space who promote immortality or extreme biohacking. “We want to bring bio-data, wearables and integrations with a lot of comprehensive blood panels as well as genes, and we’re really tailoring something unique to that individual at scale,” Smith said. “The best part about it is like we’re doing this at a really affordable price—less than $1.50 a day.”

Securing the brand wasn’t easy. “I flew across the world to get it,” he said.

The company’s platform will live across mobile and web, and will offer additional features in the coming months. Hundred Health will include a form of testing and then generate tailored protocols for each individual, spanning pillars like nutrition, diet, lifestyle, exercise, and more. 

The team behind Hundred sees the integration of BellSant as a meaningful step toward a broader goal. “We’re here to build and put a doctor in everyone’s pocket,” Smith said. “BellSant built one of the most clinically credible platforms in the space. This acquisition lets us merge velocity with depth, and bring the future of health to life faster.”

He summed it up succinctly: “Two become one, with one mission: to make precision health personal, proactive, and always on.”