Doctors helping middle-aged type 2 diabetes patients often pair continuous glucose monitors with diet talks and exercise advice, but do fitness trackers add lasting value? 
This six-month random trial published in the Diabetology and Metabolic Syndrome tested exactly that with 158 adults, median age 58 years and HbA1c near 10%. Nearly 70% used insulin already. They split into two groups: 73 wore just FreeStyle Libre CGM sensors for three two-week periods over six weeks, while 65 added a Fitbit Inspire HR tracker. Everyone got diabetes classes and food counseling. Teams checked sugar time in range, activity levels, and HbA1c at start, three months, and six months to see which setup held control best.
Sugar Control Jumps Fast in Both Groups
Both setups captured solid CGM data over 89-92% of wear time, averaging 14 days and six to seven scans daily. Time in target sugar range climbed steadily from 61% to 71% across periods, while high sugar time dropped from 35% to 25%—all highly significant. This proves education plus real-time sugar views work quick.
Trackers Stop the Three-Month Slide
HbA1c fell 1.5% in both groups by three months, no matter weight change. But from three to six months, sugars crept back. The CGM-only group rose 0.7%, while the tracker group limited it to 0.4%—a meaningful edge.
Activity Holds Key to Long Wins
The Fitbit group kept moving at steady levels, while the CGM group cut activity sharply. Trackers nudge daily steps and habits to lock in early gains.