Not all palm sugars are created equal. Coconut Palm Sugar is palm sugar but not all palm sugars are coconut sugars. It is very important to make this distinction as the two are different kind of sugars. More importantly, they do not have the same glycemic index and consequently do not have the same health benefits. The studies made by the Philippine Food and Nutrition Research Institute (FNRI) on the Glycemic Index of Coconut Palm Sugar is specific to the Coconut (cocos nucifera). You can view a copy of the Glycemic Index of Coco Sugar from the FNRI here
What's even more confusing is that in some parts of Southeast Asia, the two terms are used interchangeably. For example, Traditional Thai palm sugar are mixed regular cane sugar and or malt sugar. Traditional Cambodian palm sugar is derived from Palmyra tree. Traditional Indonesian palm sugar is made from the Aren Palm. Due to this interchanging use of terms and the gaining popularity of coconut sugar, some sellers are selling their palm sugars as "coconut sugars", although they are NOT coconut sugars. So be very careful when purchasing "palm sugar" and make sure that what you are buying is what you are expecting it to be. Also keep in mind that coconut sugar is NOT as sweet as regular sugar so it should NOT taste as sweet as regular sugar
It can be difficult to tell so how can you tell if you are buying "real" coconut sugar? .... check the label make sure that is made from 100% coconut palm or coconut sap!
If you would like to know where to get 100% coconut sugar, you can get them online or check in your local Asian grocery stores and see if they carry it.