Weight Loss/Activity not enough?

Does anyone know why my blood sugar could improve with diet, weight loss and exercise, but then worsen again? Or go back and forth?

During pregnancy with my first child in 2014, I was diagnosed with gestational diabetes. I know my troubles must have started with this pregnancy because beforehand my A1C and fasting numbers (via routine work screenings) were always normal. I was overweight when I got pregnant (5’5 and 155 lbs) and then gained way too much weight (201 by the end of the pregnancy). I was able to manage my levels through diet and a small dose of glyburide at night.

After the pregnancy, my doctor told me to keep an eye on my blood sugar readings and report back if they hadn’t normalized. I assumed they would normalize and wasn’t vigilant about checking. When I did check, they were higher than they should have been but not outrageous (stayed under 200). I was overweight and inactive, but overwhelmed with a newborn baby and didn’t take the time to go back to the doctor and fully address this.

As time went on, I committed to eating healthy and exercising. I lost weight and then started checking my blood sugar again (purchased a Relion monitor & strips from Walmart). My numbers were great – I could eat many more carbs than in the past without my BG going over 120. Pleased with these results, I stopped checking my blood sugar regularly.

Then a few months later, around Easter, I took a break from healthy eating and had candy & cake at a family gathering. I checked my BG and it was around 150. I recommitted to regular testing, watching my carbs, and weight loss. My postprandial numbers became normal and everything seemed to be working. However, it seemed no matter what I did, my morning fasting sugar was always high 90s or low 100s. Then after many weeks it seemed my postprandial numbers were trending higher.

Finally, I decided to cut out all artificial sweeteners. I had been drinking a lot of diet coke and crystal light every day. Immediately my fasting numbers went down into the 80s and my postprandial numbers were often less than 100. I thought this was the answer to my problems. But after a month of this, my fasting numbers are now creeping back up. And one night, when I was particularly hungry, I ate a large bunch of green grapes and got a reading of 200.

At this point, I am 127 lbs and exercise 3-5 times per week, which includes 20+ miles of running. I eat primarily lean proteins and vegetables and olive oil for fat. My main source of carbs is fruit, but I limit them. Why would my BG numbers fluctuate from normal to pre-diabetic/diabetic…eating mostly the same stuff?

i don’t produce enough insulin, but i am not type 1. like you, i can get by if i exercise and don’t eat lots of fruit and other carby stuff. losing weight didn’t change my situation because i wasn’t insulin resistant to begin with. i didn’t get testing for gestational diabetes because i was in taiwan when i had my children- maybe i had it then. i did have a yeast infection when i was pregnant.