There has recently been a strong level of interest associated with the consumption of cranberry juice. The cranberry (Vaccinium macrocarpon) is a very rich source of polyphenols that are associated with antiviral, antibacterial, antimutagenic, anticarcinogenic, anti-inflammatory and antioxidant properties.
Cranberry juice is no ordinary drink simply because of all the phytochemical content available in the fruit. The bioactive components of cranberry juice are unlike those of other berries. In cranberries, there is an abundance of “A-type proanthocyanidins” (PACs) as opposed to the “B-type” PACs that are rich in most other varieties of fruit. Standard levels of research have been conducted to investigate the mechanism of action that bioactive constituents are involved in, however further studies are encouraged. The majority of published and peer-reviewed studies concerning the benefits of cranberry juice target urinary tract and cardiovascular health along with some focus on oral care and gastrointestinal benefits.
Cranberry juice can lower LDL cholesterol, total cholesterol, and oxidative stress while increasing HDL cholesterol and endothelial function. Research also shows a lowering of glycemic responses and suppression of Helicobacter pylori colonization and infection.
Urinary Tract Health
There is consistent evidence showing the ability of cranberries to reduce the recurrence of urinary tract infections. A bacterial anti-adhesion response is evoked in urine after cranberry juice consumption preventing E.coli from adhering to the bladder cell receptors. If bacteria cannot stick to the cells then they cannot grow and cause infection.
Conventionally the practice of managing the urinary tract health has been mainly via the prevention of infection using low-dose antibiotic medication. However, this prophylactic treatment does pose a serious risk for developing antibiotic resistance. The most commonly studied alternative treatment to the use of heavy antibiotic therapy is cranberry. This is an important finding because antibiotic drug use can be reduced and therefore lower the risk of developing resistance to those drugs. In the case of urinary tract infections (UTIs), cranberry juice has been proven to be effective at preventing UTIs in human trials.
There has been some promising evidence showing the protective cardiovascular effects of cranberries.
A number of reasons might account for the beneficial effect of cranberry juice consumption on cardiovascular disease risk factors such as hypertension, diabetes, dyslipidemia, inflammation and oxidative stress.
Diabetes/Hypertension: Although the data is not strong, there is some support showing that an intravenous infusion of cranberry juice lowers blood pressure in anesthetized rats. However, no clinical trials show blood-pressure reducing effects after the consumption of cranberry juice in patients with diabetes or cardiovascular disease.
Dyslipidemia: In clinical studies, participants with hypercholesterolemia demonstrated that consumption of cranberry juice (320 mg/d) lowered LDL and HDL cholesterol.
Inflammation: Cranberry consumption suppresses the activation of macrophages and T cells that are exposed to proinflammatory stimuli. This causes an anti-inflammatory effect and decreases concentrations of inflammatory mediators (cytokines).
Oxidative Stress: There is a reduction in blood biomarkers of oxidative stress in both healthy volunteers and patients with cardiovascular disease risk factors after consuming cranberry juice. Increased oxidative stress and modifications of lipids and proteins can contribute to forms of inflammatory diseases and other cardiovascular insults.
It is important to understand that the consumption of a variety of different types of fruit is required daily to maintain a healthy diet, however, cranberries represent one of the richest sources of phenolic bioactive components that can contribute to the wellness and health of human beings.