Fasting seems to be really hot right now in the health and nutrition world. I’ve read how it can be helpful for insulin sensitivity, longevity, and even cancer prevention. However, as a T1D, I was nervous to try any sort of fasting for any significant period of time. I routinely practice intermittent fasting, but nothing longer than 16 hours. For example, my Saturday morning swim workout goes from 8 am to 9:30 am and I typically do this workout fasted. Thus, if my first meal of the day is after 10 am, this is roughly 16 hours.
A few weeks ago I decided to try a 24 hour fast, but I wasn’t sure how to manage basal insulin levels. I’m currently on 18 units of Lantus split into to two doses per day, 9 units around 5 am and 9 units around 5 pm. I had a routine blood test scheduled for a Thursday morning which required a minimum of 12 hours of fasting so I decided this would be the day. On Wednesday night I ate a normal dinner and took my 9 units of Lantus around 5 pm. On Thursday morning I had a glass of water and completely skipped my 5 am dose of Lantus. This meant I would be riding on half my usual basal insulin levels for the next 12 hours. Here’s what I found:
- My blood sugar hovered between 65 and 80 mg/dl all day long.
- I felt fine. I had no fluctuations in energy, no brain fog, and no insane cravings to eat an entire buffet.
- I didn’t know what to do with the free time meal prep and eating usually took up so I was very productive at work.
- I ate a normal dinner on Thursday night, thus a roughly 24 hour fast.
- I felt completely normal during my Friday morning swim workout.
All in all, I was a bit surprised how easy it was. The only confusing part was figuring out how to get back onto my split dose of 18 units of Lantus. This ended up taking about 5 days.
I’ve decided to do this once per week every Thursday. I’ll report back with updates, but all in all my anxiety regarding fasting was unnecessary. The most remarkable aspect to my experience was how unremarkable it was.