Cranberry juice can temporarily make conditions, such as acid reflux, worse because it is mildly acidic. Some people find that cranberry juice leaves an unusual taste in their mouth, or that it temporarily irritates gums and lips.
Research into the benefits of cranberry juice is mostly preliminary, but the antioxidant and antibacterial benefits look promising.
Most people can safely include cranberry juice in their diets, and they are adding a serving of fruit to their diet when they do so.
Six benefits of drinking cranberry juice
Potential benefits of cranberry juice include:
1. Fighting age-related damage
Cranberry juice may help fight age-related damage.
Chemicals called free radicals accumulate in the body as people age. Free radicals cause oxidative damage. There is a link between oxidative damage and health issues, including:
Some of the chemicals in cranberry juice are antioxidants or compounds that fight harmful free radicals. The presence of antioxidants means that cranberries and cranberry juice might help fight age-related damage to the body's tissues.
A 2011 study found that chemicals in cranberries promoted better antioxidant activity the lower their pH was. That study also found that the berries were significantly more potent antioxidants than cranberry juice, although cranberry juice still offered some benefits.
2. Improving heart health
Studies show that various ingredients in cranberry juice may improve heart health.
Cranberries are high in chemicals called polyphenols that may support heart health. A 2011 study of females with metabolic syndrome found that cranberry juice increased the antioxidants in the blood plasma. People who drank cranberry juice also had lower low-density lipoprotein (LDL). LDL is known as the "bad" type of cholesterol.
Another 2011 study found that cranberry juice could improve health in people with coronary artery disease. Mean carotid-femoral artery pulse wave velocity, which is a way to measure the stiffness of arteries, was reduced among the people in the study who drank a laboratory preparation of double-strength cranberry juice.
3. Treating or preventing urinary tract infection (UTI)
The antibacterial effects of cranberry juice were reported to reduce the incidence of UTIs in mice, according to a 2017 study in Frontiers in Microbiology.
The reduction of UTI incidence is thought to be due to the ability of antibacterial properties to reduce the colonization of Escherichia coli in the bladder. The bacteria, which is known better as E. coli, is the cause of most UTIs.
A 2016 study, reported in Alternative Therapies in Health and Medicine, showed less bacterial infections in urine cultures from uncircumcised boys who drank cranberry juice and had previously had repeated UTIs compared to those who drank a placebo and those who had been circumcised who also drank the placebo.
The authors concluded that cranberry juice might be beneficial against the growth of bacterial pathogens.
4. Supporting digestive health
There is growing evidence that the phytochemicals contained in cranberries play an important role in digestive health.
Evidence for the digestive health benefits of cranberry juice, in addition to other benefits, was reported in a study from 2018 in the Journal of the Science of Food and Agriculture.
The paper noted that inhibiting the production of another bacterium called H. pylori in the stomach is thought to promote digestive health. The researchers also suggested further research is needed on cranberry juice.
5. Preventing infections
Studies suggest that cranberries may inhibit the growth of bacterial microbes.
Some chemicals in cranberries may help fight viruses and bacteria.
A 2011 study found that cranberries inhibited the growth of seven bacterial microbes. The study did not assess whether cranberries or cranberry juice could prevent infection with these microbes in humans.
The authors of the study caution that more research is needed, but argue that cranberries might be a useful method of treating or preventing food-borne illness.
6. Supporting post-menopausal health
The risk of heart problems increases after menopause compared to the risk in all other groups of people of the same age.
A 2013 study investigated this phenomenon in rats that had their ovaries removed. Researchers found that daily cranberry consumption reduced total cholesterol, suggesting cranberry products might be useful dietary supplements after the menopause.
Side effects of cranberry juice
Some research has found that cranberry juice may interact with certain medications. One concern is that cranberries may intensify the effects of a blood thinner called warfarin.
Research on other drugs is less consistent. Preliminary research, however, suggests the possibility of interactions between cranberries and:
People taking these drugs or any other medications should talk to a doctor before using cranberry juice. It may be necessary to monitor the doses and effects on medications rather than avoiding cranberry juice entirely.
Cranberry juice is safe for most people and has several potential benefits.
The American Academy of Pediatrics recommends limiting fruit juice intake in toddlers and children and advises against giving babies juice. Parents who want to add cranberry juice to their children's diet should, therefore, only do so in small quantities and should not give them other juices.
People should choose varieties that are not from concentrate, with no sugar added, to get the most out of cranberry juice. Alternatively, a person can consider making fresh cranberry smoothies at home by putting cranberries in a blender with other ingredients. Adding a sweet fruit, such as an orange, can help it taste sweeter.
As with any diet change or supplement, people should talk to a doctor or dietitian first.