Question - What time of day are you the most resistent to the effects of insulin ?
Clinically there seems to be an increased need for insulin from about 6 to 9 AM which resulted in the term , Dawn Phenomenon.
Efforts to explain the physiology for this apparent increased need for insulin are interesting . I like a study , reported in Diabetes 38: 273-89 , 1989 - Morning Insulin Requirements , suggesting that the Dawn Phenomenon may be more apparent than real.
Their studies suggest that the " Dawn Phenomenon " may be " more related to the sleep- associated decrease in insulin requirements than any putative insulin resistance at dawn " . Other possible causes include growth hormone , glucagon and catacholamines .
The mechanism of the increase in morning glucose may be unsettled. However, the reality of the increase is there and has to be considered when adjusting insulin and other medications to correct fasting glucose results into specific target ranges.
Adjusting medications to correct your fasting glucose without monitoring 3 am glucose may increase the risk of nocturnal hypoglycemia.
Have fun , Be Smart and remember , unrecognized hypoglycemia is common , and your 3 am glucose may be lower than your 8 am glucose
David Calder, MD