What's the Glycemic Index of Prunes?

Prunes are a fruit with an undeservedly bad reputation. The high fiber content of prunes is commonly associated with regulation of bowel habits, but prunes have many other redeeming factors. For example, prunes have an extraordinary amount of antioxidants.

In fact, according to ​The 150 Healthiest Foods on Earth​, they contain more antioxidants than any other fruit. If you're looking to incorporate prunes into your diet while monitoring your blood sugar, you may be curious to find out their glycemic index, or the effect prunes can have on your blood sugar.

The glycemic index of food is a simple way to determine the impact the sugar in a food will have on blood sugar levels. The body quickly absorbs foods with higher glycemic indices, typically 70 and above, raising blood sugar levels, according to Harvard Health Publishing. By consuming a food with a lower glycemic index, below 55, you can avoid the quick rise in blood sugar.

The glycemic index for one serving of prunes (60 grams, or about six prunes) is 29. Keep in mind that this glycemic index is for unprocessed, unsweetened, dried prunes.

Many commercially sold prunes and prune products are artificially sweetened, flavored and processed, substantially increasing the glycemic index. For example, the glycemic index of a 250-gram serving of prune juice is 43.

As fruits, prunes carry higher sugar content than other foods, such as vegetables. But compared to other common fruits, such as bananas, apples and watermelons, all ranging between 39 and 72, prunes have a relatively low glycemic index, and thus a smaller impact on blood sugar levels. This low glycemic index reflects the high fiber content in prunes.

The American Diabetes Association considers low glycemic foods to have a glycemic index rating of less than 55; a moderate glycemic food rates between 56 and 75, and a high glycemic food has a rating of between 76 and 100. The overall impact glycemic index has on blood sugar is the average of all foods consumed in a sitting.

Therefore, pairing high glycemic index foods with low glycemic index foods will result in a less dramatic increase in blood sugar than if the high glycemic index food were consumed alone. An example of this is combining cheese with bread. The low glycemic index of cheese decreases the glycemic index of bread, creating an overall moderate glycemic index.

Finally, more processed foods generally have a higher glycemic index than unprocessed foods. For example, reaching for the lower glycemic index unprocessed prunes over prune juice will result in a less dramatic increase in blood sugar.