Unsweetened cranberry juice contains meaningful amounts of vitamins C, E, and K, along with smaller quantities of several B vitamins. An 8-ounce cup provides roughly 23 mg of vitamin C, about 3 mg of vitamin E, and nearly 13 micrograms of vitamin K. It’s not a vitamin powerhouse compared to orange juice or leafy greens, but it brings a unique combination of nutrients and plant compounds that few other juices offer.
Vitamin C: Present but Easily Lost
Vitamin C is cranberry juice’s most recognized nutrient, but the amount you actually get depends heavily on how the juice was processed. A cup of unsweetened cranberry juice starts with roughly 23 mg of vitamin C, which covers about 25% of the daily target for most adults. That sounds decent, but it’s far less than orange juice, which delivers around 124 mg per cup.
The bigger issue is that vitamin C is the least stable of all vitamins. Pasteurization at high temperatures can destroy about 35% of the original vitamin C content, and sterilization pushes losses to over 50%. Even the basic steps of crushing and pressing the cranberries activate enzymes that break down vitamin C before heat is ever applied, with losses of 26 to 31% at that stage alone. By the time bottled cranberry juice reaches your glass, a significant portion of its original vitamin C is gone. This is one reason many commercial brands add vitamin C back in during manufacturing, so check the label to see whether yours is naturally occurring or fortified.
Vitamins E and K
Cranberry juice is an uncommon source of vitamin E among fruit juices. A cup of unsweetened juice provides about 3 mg of alpha-tocopherol, which is roughly 20% of the daily recommendation. Vitamin E acts as a fat-soluble antioxidant, protecting cell membranes from damage. Most people associate it with nuts and seeds, so finding a meaningful amount in a fruit juice is notable.
Vitamin K shows up in cranberry juice at around 13 micrograms per cup. That’s a modest contribution toward the 90 to 120 microgram daily target, but it adds up if you drink cranberry juice regularly. Vitamin K plays a central role in blood clotting. If you take blood-thinning medication, the vitamin K content in cranberry juice is worth knowing about, since it can interact with how those medications work.
B Vitamins in Small Amounts
Cranberry juice contains traces of several B vitamins, though none in amounts that would make a real dent in your daily needs. Per cup, you’ll find small quantities of riboflavin, niacin, vitamin B6, and folate. Vitamin B12 is absent entirely, which is expected since B12 comes almost exclusively from animal sources. These B vitamins help your body convert food into energy and support nervous system function, but cranberry juice isn’t a practical way to get them. You’d need to rely on whole grains, meat, legumes, or fortified foods for meaningful B vitamin intake.
Beyond Vitamins: Polyphenols and Antioxidants
The most distinctive nutritional feature of cranberry juice isn’t any single vitamin. It’s the dense concentration of plant compounds called polyphenols, particularly a group known as procyanidins. These are the same compounds responsible for cranberries’ famously tart, astringent taste. A single serving of cranberry beverage can contain nearly 200 mg of procyanidins along with about 24 mg of flavonols.
These compounds function as antioxidants in the body. Research published in the Journal of Agricultural and Food Chemistry found that drinking cranberry juice measurably increased antioxidant levels in the blood at every time point tested, compared to a control drink that actually caused a slight decrease in antioxidant capacity. In practical terms, cranberry juice appears to do more antioxidant work through its polyphenols than through its vitamin content alone. Vitamins C and E contribute, but the procyanidins and flavonols carry much of the load.
Minerals Worth Noting
Cranberry juice also supplies a couple of trace minerals. A cup of unsweetened juice contains about 0.14 mg of copper, which is roughly 15% of the daily recommendation. Copper supports immune function and helps your body produce red blood cells. Potassium and manganese are also present in small amounts. None of these make cranberry juice a primary mineral source, but they add to the overall nutritional picture.
Pure Juice vs. Cranberry Cocktail
What you see labeled “cranberry juice” at the store varies enormously. Most products on grocery shelves are cranberry juice cocktails, blends that mix cranberry juice with water, added sugars, and sometimes other fruit juices. Some contain as much added sugar as soft drinks. A cup of standard cranberry juice cocktail has around 30 grams of sugar, while a 100% juice blend still contains about 26 grams, though that sugar comes from fruit rather than added sweeteners.
Pure, unsweetened cranberry juice is the best option for getting the most vitamins and polyphenols per calorie. It’s intensely tart, which is why most people dilute it or mix it with water. When a label says “100% juice” or “100% real juice,” it generally means no sugar was added, but it may still be blended with other juices like apple or grape. For the highest concentration of cranberry-specific nutrients, look for bottles labeled as pure cranberry juice with no other juices listed in the ingredients. The vitamin and antioxidant profile shifts significantly once cranberry juice is diluted with cheaper, sweeter juices that don’t carry the same polyphenol density.
How Processing Affects What You Get
The general rule in food science is that when vitamin C is well retained during processing, other nutrients tend to survive too. Since vitamin C is the most fragile vitamin, it serves as a useful indicator. Cranberry juice that has been heavily heat-treated or stored for long periods will have lost not just vitamin C but likely some of its vitamin E and polyphenol content as well. Juice sold refrigerated or minimally processed tends to retain more of its original nutrient profile than shelf-stable bottles that have been sterilized at high temperatures. Cold-pressed or lightly pasteurized options, when available, preserve more of the heat-sensitive compounds.