How Brendan brought his A1C out of prediabetic range—and dropped 50+ pounds
A San Francisco bus driver discovered that real-time glucose data was the missing piece in his decade-long struggle with blood sugar management.
Who: Brendan, 55
Where: San Francisco, CA
Time with Levels: 1 year
Most Useful Takeaway: CGM data revealed glucose spikes that finger-prick testing was missing, allowing him to catch problems in real time and take immediate action with exercise or dietary adjustments.
What led you to focus on your blood sugar?
Around 2012, a nurse practitioner told me my A1C tested at 5.7 and that I was prediabetic. For years after that, I got my blood drawn every 90 days. I had this idea that I should avoid becoming diabetic, but I wasn't really changing my eating habits. The concept of "prediabetic" became a trap---I could tell myself, "I'm just prediabetic, it's not that serious." That enabled many years of carelessness.
Then I became a bus driver for San Francisco's MUNI in 2017. It's a job with very little break time and massive amounts of stress. During the pandemic, I got COVID and went into a 20-day isolation where I just ate whatever I wanted through delivery apps. When that was over, I'd ballooned from 295 to over 310 pounds. By October 2022, my blood tests showed an A1C of 6.5---the number I'd always told myself I wouldn't reach. I messaged my doctor in a panic, and he wrote back, saying 6.5 indicates damage to your pancreas that's irreversible. That made me completely freak out.
What made you decide to try a continuous glucose monitor?
I had joined a diabetic support group on Facebook and was using a finger-prick glucose meter. People in the group told me that while finger-pricking was good, I'd be missing a lot of spikes if I wasn't obsessively testing all the time. They were right---there would be spikes I wasn't aware of.
I asked Kaiser to give me a CGM, but they don't want to prescribe them unless you're on insulin and in danger of low blood sugar events, which wasn't my situation. A friend's husband who had prediabetes had gotten Levels and was happy with it. I thought it would cost thousands of dollars, but when I found out it was $200 for the app and Levels service, and $200 a month for sensors [now $100], I decided just to do it.
What did the CGM reveal that finger-prick testing couldn't?
The most important thing was catching those spikes in real time. In February 2025, I went to a restaurant with a friend and ordered a salad. I knew it had some ingredients that weren't compliant with my eating guidelines---candied walnuts---but I thought it would be okay. I hadn't been real with myself about the amount of sugar that might be in the dressing.
I'm sitting there enjoying the salad, periodically checking the Levels app, and the next thing I know, my blood glucose is 180 or 190. The app told me that vigorous exercise could control a spike, so I ran out and hiked up the closest hill for 20 minutes. Without the CGM, I would never have known that salad spiked me that high.
How has your health changed over the past year?
I started making serious changes after that first October 2022 scare. Within six months, my A1C dropped from 6.5 to 5.7. I lost a significant amount of weight through low-carb eating and lifting weights at the gym. However, after that initial improvement from being "scared straight," my A1C began to climb back up, with me seeing numbers like 5.8 and 5.9. Then, something unfortunate and fortunate happened---in June 2025, I injured my back and ended up on light duty at work.
From July through September, instead of driving a bus, my employer had me hiking all over San Francisco doing transit ambassador work, which included taking down old posters, putting up new ones at bus stops. I was walking eight hours a day, going up and down the city's famous hills. Sometimes I'd burn 1,500 or 1,600 calories just from walking. My most recent blood draw in late September showed my A1C at 5.6---down two full points in 90 days. Right now, I weigh 261 pounds, down from over 310.
What have you learned about managing your blood sugar day to day?
I've become much more interested in my stability score and standard deviation numbers, especially after Levels switched to the Stello sensor, which you can't calibrate with a finger stick. I realized I need to focus less on whether the exact number is accurate and more on the patterns---whether I'm having spikes or staying stable.
I've also learned about my morning glucose. My version of the dawn phenomenon involves a spike after I wake up and start my day. I experimented a lot with my morning coffee routine because I'd be driving to work and my blood glucose would shoot up to 140 or higher after just coffee with heavy cream and Splenda. It's been a negotiation with myself to figure out what works.
The biggest change came from eliminating late-night eating of things like Atkins bars, which were triggering my compulsive overeating. Even though the bars didn't spike my glucose much, they were keeping me plateaued. During the weeks when I don't eat them, my average blood glucose has been 105---way lower than usual. My dawn phenomenon has become much less noticeable, too.
What would you tell others who are struggling with prediabetes?
Once you have the glucose monitor, it's hard to imagine living without it. It forces me to be real with myself. There are so many situations where it's easy to think, "It's not so bad if I just put a little bit of this dessert in my mouth." But the CGM shows you the truth.
The flip side is that sometimes it validates that it was actually not a complete disaster to eat something your diabetic support group might frown on. It's been educational to notice which foods aren't spiking me that I know people in my support group would disapprove of---though I'm sure some of those foods are probably hurting me in other ways even without a glucose spike.
Overall, Levels and the CGM have been amazing tools. Without them, I wouldn't have known about my morning spikes, my response to restaurant food, or how exercise brings my numbers down in real time. It's truly been life-changing.
Take control of your health with Levels
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