Brief Answer:
Not a simple answer. Please read on.

Detailed Answer:
Hello,
you haven't mentioned whether you're diabetic or not and your glycosylated hemoglobin (HbA1c) if you are. Your fasting blood sugar implies an 'impaired fasting glucose' state and does not document the diagnosis of diabetes but I could not possibly know if your postprandial glucose is high or not. I'll try to give you the best possible answer, taking into account the lack of information.
People with impaired glucose control have three 'weapons' to fight against it:
- diet: a healthy body weight and a healthy diet is essential. No drug/treatment regimen can substitute for a healthy diet. If you need more information on diet, please ask.
- exercise: It has to be daily. Thirty minutes of walking every day is sufficient. Of course, if you already do more than that then you should carry on doing it.
- drugs: there is a multitude of drugs targeting high blood glucose. I know you don't want to take medications and I can't tell if you need them because I could not be sure whether you have diabetes or not.

Since you're already exercising and you don't want to take drugs, targeting your body weight is a good way to go. If you're overweight, you should aim for some weight loss. If you're not, then there's not much you could do for FASTING morning blood glucose.
The fasting blood glucose does not directly relate to the food. It's more related to insulin resistance. The only thing you could do for your insulin resistance during your sleep is to loose some weight, if you're overweight.
If you're not then I'm afraid that only drugs can do something about it, although - as I already made clear - drugs are not needed if you're not diabetic. Impaired fasting glucose is not an indication for drug therapy.
Also please note that glucose below 80mg/dL is difficult and pointless to target. No harm occurs with fasting blood glucose levels below 100mg/dL. The documented problems begin when fasting blood glucose rises above 125mg/dL and that's why the diagnosis of diabetes requires glucose levels equal to or above 126mg/dL.
And please keep in mind that other medical conditions can affect blood glucose control like your thyroid function. If you haven't done a Thyroid Stimulating Hormone (TSH) test then you should!
I hope I've shed some light on your situation.
If you need more information, please ask again and I'll be glad to provide further details. If you do, please also include the information I asked for that is whether you have diabetes or not and your glycosylated hemoglobin level.
Kind Regards!

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