Frozen strawberries do contain more added sugar than fresh strawberries.
That is unless you grow the strawberries yourself and then freeze the homegrown strawberries.
But commercially packaged and grown strawberries do have added sugar to make them more sweet and to help preserve them.
Commercially packaged and produced frozen strawberries contain at least 70 percent sugar when compared to the fresh strawberries that contain only 4.9 percent sugar.
The sugar in fresh strawberries is healthier sugar though.
If you're diabetic you should avoid eating too many frozen strawberries but fresh strawberries are healthier for those who have diabetes.
Both fresh and frozen strawberries are healthy but the frozen strawberries are higher in sugar which could cause weight gain and a spike in blood sugar levels as well.