Had blood tests done,fasting glucose showed 90 and last month it was only 79.i started taking l-glutamine,is it the cause?no symptoms.worried.is 90ok?

Normal: This is normal biologic variation. Glutamine/L-glutamine has been promoted as helpful in muscle building, but there is little evidence of this in healthy individuals. It does seem to be helpful in disease states such as cancer treatment, wound healing and AIDs. Both of the fasting glucose results you report are normal; the third one could be 90... or 80, etc. Normal is <100 mg/dl.