Dates are not dried plums. They are two completely different fruits from unrelated plants. Dates grow on palm trees in hot desert climates, while dried plums (also called prunes) come from plum trees in temperate orchards. The confusion likely stems from their similar appearance: both are dark, wrinkled, sticky, and sweet. But that’s where the overlap ends.
Why They Look So Similar
Dates come from the date palm (Phoenix dactylifera), a tree that thrives in extreme heat and needs less than three inches of rain per year. They’re harvested by hand in temperatures that can reach 120°F, with workers lifted into the canopy on forklifts to pick fruit that ripens one piece at a time. Dates are not actually dried at all. They lose moisture naturally on the tree as they ripen, which is why they arrive chewy and dense straight from the branch.
Dried plums, on the other hand, start as fresh plums grown on deciduous fruit trees in cooler climates like California’s Central Valley or parts of France. After harvest, the plums are mechanically dehydrated to become what most people know as prunes. In 2000, the U.S. Food and Drug Administration granted permission to market prunes under the name “dried plums” as an alternative label, largely because the industry wanted to shake the old-fashioned image the word “prune” carried. Outside the U.S., they’re still called prunes.
Nutritional Differences
Both fruits are calorie-dense and high in natural sugar, but their nutritional profiles diverge in meaningful ways. A serving of five prunes contains about 104 calories, 17 grams of sugar, and 3 grams of fiber. Dates tend to pack more sugar per serving, with Medjool dates running higher in total calories for a comparable portion.
Dried plums are notably rich in vitamin K, potassium, and magnesium. Per 100 grams, prunes deliver roughly 732 milligrams of potassium (about 15% of the daily target), nearly 60 micrograms of vitamin K (about 74% of the daily value), and 41 milligrams of magnesium. This mineral combination is one reason prunes have been studied extensively for bone health. Dates are a solid source of potassium and some B vitamins but don’t match prunes for vitamin K.
Blood Sugar Impact
Despite their intense sweetness, dates have a surprisingly wide range of glycemic index values depending on the variety. Research measuring different date cultivars found glycemic index scores ranging from about 43 to 75, meaning some varieties spike blood sugar moderately while others push closer to high-glycemic territory. Prunes generally fall in the low-to-moderate glycemic range, partly because their fiber and sorbitol content slows sugar absorption.
Which One Helps With Digestion
Prunes have the stronger reputation for relieving constipation, and the science backs it up. Both fruits contain fiber and sorbitol, a sugar alcohol that the body can’t fully break down during digestion. When sorbitol reaches the colon, the body works to flush it out, which stimulates a bowel movement. Prunes contain more sorbitol than dates do, which is why they’re the more reliable choice if regularity is the goal. Dates still contribute useful fiber and some sorbitol, but the effect is milder.
Using Them in the Kitchen
In cooking and baking, dates and prunes serve similar roles as natural sweeteners and fat replacements, but they aren’t identical substitutes. Both add moisture and sweetness, and either one can be blended into a paste (one cup of pitted fruit with three-quarters cup of hot water, blended smooth) to replace butter or sugar in recipes. The paste keeps in the refrigerator for about a week.
Chopped dates work as a 1:1 swap for chocolate chips or candy pieces in cookies, granola bars, and banana bread. Prune paste tends to have a slightly more tart, complex flavor that works well in chocolate baked goods, where its deeper taste blends in. Dates lean sweeter and more caramel-like, making them a better fit for energy balls, smoothies, and sticky desserts.
If a recipe calls for one and you only have the other, the swap usually works fine. The main thing to watch is moisture: dates are generally stickier and denser, so you may need a splash more liquid when substituting prunes for dates, and slightly less when going the other direction.