15 Years Younger: Professor Dean Ho Uses His Own Body to Study Aging

Professor Dean Ho, a biomedical engineer at Singapore's National University, embarked on a transformative study to explore the impact of lifestyle modifications on aging. The DELTA intervention protocol, which involves time-restricted feeding, strength training, cardiovascular exercise, a Mediterranean diet, and supplementation, was the focus of this unique research. As the sole participant, Ho's body served as the living laboratory for the study.

After approximately eight months of continuous monitoring, an artificial intelligence system estimated Ho's biological age to be around 32 years old, more than 15 years younger than his actual age of 47. It is important to note that this does not imply that Ho literally became 15 years younger. Instead, the AI model derived the estimate from physiological and molecular data collected throughout the experiment.

The study utilized wearable devices such as the Whoop, Garmin, and Apple Watch to continuously measure various aspects of Ho's health. These measurements were combined with physiological and molecular data to provide a comprehensive picture of his well-being. Ho adopted several lifestyle changes during the study, including fasting for about 20 hours on certain days and engaging in multiple 48-hour fasts.

He also incorporated around 90 minutes of strength or cardiovascular exercise into his daily routine and adhered to a diet rich in leafy greens, seeds, olive oil, and lean protein.

Several physiological measurements underwent notable changes during the study. Ho's metabolic switching time, which measures the speed at which the body transitions between burning glucose and fat for energy, improved from over 24 hours to 16.5 hours. This marked a significant difference compared to the 36 to 72 hours typically required by peers of a similar age.

Additionally, Ho's resting heart rate decreased from 65 to 46 beats per minute, and he increased his sleep from approximately five hours to nearly eight hours per night. His bedtime shifted from after midnight to around 9 p.m., and his sleep patterns showed more deep sleep and less time spent awake during the night. The study also recorded changes in Ho's gut microbiome, with Fusobacterium becoming undetectable during the experiment.

While the AI system estimated Ho's biological age to be 32 years old, it is crucial to understand that this does not establish that he possesses the same disease risk, physical capacity, or expected lifespan as an average 32-year-old. The estimate represents an assessment produced by a specific model using data from a single individual.

The DELTA study, while groundbreaking in its approach, has certain limitations. As an N-of-1 study, it cannot determine whether other individuals would experience similar physiological changes through fasting, exercise, diet, or changes in sleep patterns. Furthermore, it cannot ascertain the extent to which each intervention contributed to the observed results.

Despite these limitations, the DELTA study represents an ongoing effort to understand personalized health beyond conventional clinical trials. The researchers aim to leverage continuous health data to identify changes that could potentially guide individualized medical decisions. The next phase of the study will determine whether the patterns observed in Ho can be replicated in larger groups, paving the way for the validation of continuous monitoring and AI-based biological-age models as reliable tools for longevity research beyond a single subject.