After more than a decade of trying and failing to lose weight, Daniel Abeyta, 43, of Redwood City, California, says he was ready for something different. “I was doing a lot of dieting … and it wasn’t working,” he tells TODAY.com.
Then, while scrolling social media, he came across the Simple app and decided to give it a try. The Simple app describes itself as “practical AI coaching that guides you daily — without diets, food restrictions, or judgment — toward lasting weight loss.”
Over the course of about a year, Abeyta went from 315 pounds to around 155 pounds. He’s kept it off for over a year and still uses the app to help him maintain his new weight.
His story highlights a growing trend of people turning to artificial intelligence for personalized diet advice, meal planning and accountability. An estimated one in four Americans uses AI tools for health information or advice, often because they want fast answers or have felt ignored by providers in the past, according to a new study by the West Health-Gallup Center.
While experts say these tools can be helpful, they also come with important caveats.
Why Abeyta Turned to AI
For Abeyta, one of the biggest barriers to weight loss before using the app was simply not knowing how to begin.
“I didn’t know where to turn,” he says. “So I would turn to the app and ask questions, like ‘What can I eat? What do you recommend?’ and it would give me recipes and ideas.”
The AI chatbot became a kind of on-demand coach, offering meal suggestions, answering nutrition questions, and even providing step-by-step recipes based on his preferences. Over time, it also learned what he liked and adjusted recommendations accordingly.
The app didn’t just focus on food, it also introduced structure. Abeyta used it to follow an intermittent fasting schedule, starting with a 14-hour fasting window and gradually extending it. The app would prompt him when to eat and when to wait, helping him stay consistent. “It gives you a schedule … like, ‘You can eat now’ or ‘You shouldn’t eat now,’” he explains.
At first, Abeyta’s approach was extreme. He began with mostly liquids, then slowly reintroduced solid foods, shifting toward lean proteins, fruits, vegetables and nuts. He also worked “hand in hand” with his doctor, since he had a history of gallstones and thyroid issues, he says.
As the weeks went on, the results started to reinforce his efforts. “Once I started seeing changes … it forced my mind to be like, ‘OK, you got this, it’s working,’” he recalls.
Before this journey, Abeyta describes his eating habits as heavily reliant on fast food and convenience meals. “As long as it was easy to grab, I would eat it,” he says.
Switching to mostly whole, home-cooked foods felt like a shock at first. But he says the app helped bridge that gap by offering simple, realistic ideas he could follow. It also added an element of motivation, with small nudges and encouragement built into the experience. “It (says) things like, ‘You’re doing great today’ or ‘You met your hydration goals,’” he adds.
He also saw multiple non-scale victories. Abeyta says he reversed his prediabetes, reduced his joint pain and improved his overall mobility. Daily tasks that once felt difficult, like climbing stairs, are now a regular part of his everyday life. “You feel it physically, and you feel it mentally,” he says.
The Rise of AI-Powered Nutrition Apps
Apps like Simple are part of a rapidly growing category of AI-powered health tools that promise to deliver personalized guidance instantly.
Other popular apps — like MyFitnessPal, Noom, Foodvisor, SnapCalorie and Eat This Much — help with weight loss by combining features such as photo-based food-logging, calorie and macro tracking, personalized meal planning, and AI-driven coaching. Across these apps, users can access real-time nutrition analysis, habit and behavior insights, progress tracking, and adaptive recommendations based on goals and eating patterns.
In other words, many of these platforms act like interactive nutrition assistants. Users can ask questions in real time, get tailored meal ideas, and receive feedback based on their habits. That convenience is a big part of the appeal, especially for people who feel overwhelmed or unsure about their first steps.
Pros and Cons of AI
Registered dietitian Theresa Gentile says these apps can be a helpful entry point for people trying to build healthier habits. “They decrease the friction to some of these healthy behaviors, like checking in daily, being mindful of what you’re eating, and accountability of portion sizes,” she tells TODAY.com.
In her view, the biggest benefit is accessibility. She says the apps can make it easier to stay in touch with your body and mindful of what you’re eating while maintaining a sense of accountability. For some people, especially those who may feel uncomfortable seeking help in person, that’s enough to create real change, she adds.
At the same time, Gentile emphasizes that AI lacks the clinical judgment and personalization of a human professional. “A lot of the apps center on numbers, like calories and weight, because they don’t get the nuance in between,” she explains.
That can lead to overly rigid recommendations or plans that don’t fully account for someone’s lifestyle, stress levels or medical needs, Gentile says. In some cases, users may become too reliant on the app, following its guidance without questioning whether it truly fits their body.
Abeyta says he noticed some of these limitations early on, especially when the technology was less advanced. “At times, (the app) would get confused,” he says. “They call it hallucinating … but it’s getting better now.”
Gentile warns that even small AI errors can have serious health consequences, especially for conditions like diabetes, so it’s important to watch for miscalculations, oversimplified advice or a lack of personalization for medical needs.
Instead of blindly following recommendations, she encourages users to take note of how they feel when following AI-generated advice. Persistent hunger, fatigue, dizziness or difficulty concentrating may signal that something isn’t right.
“You shouldn’t be walking around really hungry,” she emphasizes.
She also cautions against overly rapid weight loss. Losing weight too quickly can sometimes indicate that calorie intake is too low or unsustainable in the long term. Gentile recommends aiming to lose no more than 1–2 pounds per week. If you’re losing weight faster or experiencing fatigue, poor focus or constant hunger, your calorie intake is likely too low.
If you’re interested in starting a weight-loss journey, talk to your doctor or a registered dietitian.
Using AI as a Tool
For people curious about AI nutrition apps, experts say the key is to treat them as one tool, not a total solution. “They should help you feel more in tune with your body, not controlled by rules,” Gentile says.
Used thoughtfully, these apps can provide structure, ideas and accountability. But lasting change still depends on building habits that you can maintain for years to come. Gentile often compares tracking tools to “training wheels” — they are helpful at first, but not something you should use forever, regardless of whether they’re powered by AI.
For Abeyta, the combination of personal commitment, accountability and meal suggestions made all the difference. “It wasn’t easy at first,” he says. “But if you stick with it … you’re going to thank yourself.”
As AI continues to reshape the way people approach health and nutrition, his story offers a glimpse into what’s possible — and a reminder that the most effective way to improve health is small, sustainable changes made over time.