Can logging steps prevent disease?


February 15, 2023

Study finds walking more than 8,200 steps a day protects against developing obesity, sleep apnea, GERD and depression.

Chronic conditions like obesity and high blood pressure are associated with heart attacks, stroke and cancer – some of the biggest killers in the U.S. and some of the costliest burdens on our health-care system and society. What if people could avoid developing them simply by taking more steps each day? And can we support this theory using the real-life data generated by fitness watches and trackers?

These are the questions that a group of researchers from Vanderbilt University Medical Center set out to explore. By digging into the medical records and fitness data from thousands of volunteers, they discovered that taking more steps per day is associated with preventing numerous chronic conditions. Turns out your fitness watch might just be the real-world ally you and your doctor want on your wellness team.

More steps a day keeps the doctor away

Dr. Evan Brittain and colleagues reported their research in the prestigious journal, Nature Medicine. The study looked at data from more than 6,000 participants who are part of the nationwide All of Us project and agreed to wear Fitbit activity trackers at least 10 hours a day and provide access to their electronic medical records. This wealth of information allowed the researchers to compare the health of this group to a control group of people of similar age, race and other demographics. The data covered about four years instead of a single snapshot in time, so the researchers were able to explore the links between activity levels and the likelihood of developing new conditions over time.

“What we found was clear: as the number of steps increased, the risk declined for most conditions,” said Brittain, who sees patients at the Vanderbilt Heart and Vascular Institute.

“What we found was clear: as the number of steps increased, the risk declined for most conditions.”

Specifically, taking more than 8,200 steps per day, or about 4 miles, was associated with lower likelihood of developing obesity, sleep apnea, gastroesophageal reflux disease (GERD, or chronic acid reflux) and major depressive disorder.

The data suggests that people who are overweight can reduce their risk of becoming obese by 64% by increasing daily steps from 6,000 to 11,000.

This relationship was also true for high blood pressure and diabetes, but only up to a certain point. After participants reached about 8,000-9,000 steps per day, taking additional steps did not increase the likelihood of preventing these conditions.

Volunteers’ fitness data fuels findings

One of the unique things about the study has to do with the large amounts of data required.

There has long been evidence that living a sedentary lifestyle increases the risk for developing chronic conditions. Researchers assumed the opposite was true – move more, prevent disease – but this was difficult to prove. Older approaches relied on surveys in which participants were required to recall and record their activity levels. Using wearable fitness trackers is much more reliable than depending on memory. The issue? Fitness trackers produce a lot of data.

“Dealing with that amount of data is like drinking from a firehose,” Brittain said. “You can’t do it without help from people trained in working with large datasets.”

Thankfully, team science is the name of the game at Vanderbilt, and Brittain had the help of computer scientists and statisticians.

Should you show your doctor your Fitbit?

While the study did not address all questions surrounding the benefit of wearing fitness trackers, the results do lead us to ask “what’s next” for the not-so-distant future of wearable health technology.

“It’s likely these tools will help people take a more proactive role in their health.”

“When you go in for a checkup with your doctor, could they pull up information about your fitness activities, blood sugar, sleep patterns, etc. from your wearable devices? It’s likely these tools will help people take a more proactive role in their health and give health-care providers vital information to tailor their recommendations,” Brittain said. “It’s already possible, and studies like these get us closer to a future where it’s commonplace.”