Ask the Diabetes Educator Archive

Q:
Does grapefruit or grapefruit juice affect insulin or cause blood sugar to have a higher reading?

A:
Primarily, amounts of any food is a big determinant of rise in blood sugars. Juices in particular give a fairly immediate surge. Of all the fruit juices, grapefruit is the least sugary. Eating the fresh fruit is always preferable to juice, as digestion is a bit slower. Test your blood sugar before and 15 minutes after drinking 6-8 oz. of grapefruit juice on an empty stomach to see what the rise is. Usually, we caution to limit juice to 4 oz. Visiting our Archives section will give you lots of answers to questions on how foods impact blood sugars. With close attention, you will come to know what works better for you.