Some restaurants are serving sweet potato fries instead of regular french fries. how do their nutritional values compare?

Processed food - meh: Doubtful if fresh cut. Processed food is all about additives and salt. Both potatoes and sweets have nutrients. Balanced diet is key. Don't make a habit of all brown meals.

Glycemic Index: White potatoes typically have a G.I. Of 85/100. Sweet potatoes have a G.I. Of 37/100. The G.I. Tells you how simple or complex the carbohydrate is, that is how quickly it turns into sugar in your body. A G.I. Of 55/100 or less is generally desirable. This is particularly important if you are Insulin resistant or diabetic. High G.I. Foods make you put on fat, usually around the midline gut.