Check out this answer from Consensus:
The scientific evidence supports several health benefits of cranberry juice, particularly in improving cardiovascular health, managing metabolic syndrome, and preventing UTIs. While more research is needed to fully understand the mechanisms and long-term effects, incorporating cranberry juice into the diet appears to offer several potential health advantages.
Cranberry juice has long been touted for its potential health benefits, particularly in the realms of cardiovascular health, metabolic syndrome, and urinary tract infections (UTIs). This article explores the scientific evidence supporting these claims, drawing on recent research findings.
Cardiovascular Health Benefits
Antioxidant Properties
Cranberries are rich in polyphenols, which are known for their antioxidant properties. A study involving women with metabolic syndrome found that low-energy cranberry juice significantly increased plasma antioxidant capacity and decreased lipid oxidation markers1. Another study with healthy volunteers showed that daily consumption of cranberry juice increased plasma vitamin C and total phenol concentrations, although it did not significantly alter other antioxidant biomarkers2.
Cardiometabolic Risk Reduction
Cranberry juice has also been shown to lower several markers of cardiometabolic risk. In a study involving adults, low-calorie cranberry juice consumption was associated with reduced fasting serum triglycerides, lower C-reactive protein levels, and decreased diastolic blood pressure3. These findings suggest that cranberry juice can improve several risk factors associated with cardiovascular disease.
Vascular Function
A study on healthy men demonstrated that daily consumption of whole cranberries improved endothelial function, as measured by flow-mediated dilation (FMD). This improvement was linked to specific cranberry polyphenol metabolites in the plasma5. These results indicate that cranberry consumption can have sustained vascular benefits.
Metabolic Syndrome and Diabetes
Glycemic and Lipid Profiles
Cranberry juice enriched with omega-3 fatty acids has been shown to improve glycemic control and lipid profiles in patients with type 2 diabetes and periodontal disease. The study found significant reductions in glycated hemoglobin and increases in high-density lipoprotein cholesterol (HDL-C) levels4. Another study reported that reduced-energy cranberry juice increased adiponectin levels and decreased homocysteine, which are beneficial for metabolic health8.
Inflammatory Markers
In overweight individuals, cranberry juice consumption was associated with a decrease in serum levels of tumor necrosis factor-alpha (TNF-α) in males and an increase in interleukin-8 (IL-8) in females. These changes suggest a potential anti-inflammatory effect of cranberry juice7.
Urinary Tract Infections (UTIs)
Prevention in Women
Cranberry juice has been widely studied for its role in preventing UTIs. A randomized, double-blind, placebo-controlled trial found that daily consumption of a cranberry beverage significantly reduced the number of clinical UTI episodes in women with a recent history of UTIs9. This suggests that cranberry juice can be an effective preventive measure against UTIs.
Prevention in Children
The effectiveness of cranberry juice in preventing UTI recurrences in children has also been investigated. A study involving children treated for UTIs found that while cranberry juice did not significantly reduce the number of children experiencing a recurrence, it did reduce the total number of UTI episodes and the need for antimicrobial use10.