Hi lyndarling,
I was told (about 5 years ago) I was borderline diabetic. I didn't go to the doctor's again until a short while ago, nor did I take much notice at the time.
I had to visit the doctor recently with another problem and thought, whilst I was there, I'd mention how I was feeling.
I've ended up being diagnosed with diabetes (type 2), high blood pressure, high cholesterol and high blood sugar (amongst other things).
I think what the doctor is telling you is, to perhaps modify what you consume and take more care with your general lifestyle, exercise and eat healthily.... and you might not become a diabetic.
I wish now that I had taken more notice 5 years ago.
There are no guarrantees in life, but hopefully, if you follow a more proactive lifestyle you can avoid becoming diabetic.
Good luck.