5 Health Benefits of Cranberries
By Eric Madrid MD
Cranberries are a common small, dark red berry with many health benefits. Cranberries are so rich in antioxidants and vitamins that many are making this special—and powerful—fruit a regular part of their diets beyond that holiday cranberry sauce.
Cranberry Nutritional Benefits
One cup or 220 grams of chopped cranberries contains:
Excellent Source of Antioxidants
The process of oxidation occurs when the body is damaged by environmental stressors, dietary stressors or, simply, the stresses of everyday life. Antioxidants help reduce the effects of these aggressors on our bodies, helping to protect against cellular damage. Cranberries are considered a superfood by some due to their high antioxidant and rich nutritional content, and they also contain phytochemicals such as vitamin C, flavanol polyphenols, proanthocyanidins (PACs).
According to a 2009 study in The American Journal of Clinical Nutrition, over seven percent of people age six and older were vitamin C deficient when their blood was tested. More than half of those surveyed consumed low amounts of vitamin-C-rich foods. Just one serving (100 grams) of cranberries provides 25 percent of the Recommended Daily Allowance of vitamin C.
Cranberries are a great source of the polyphenol quercetin, a potent antioxidant that scientists have found to have anti-inflammatory effects and cardiovascular benefits. Some studies also demonstrate that quercetin has some positive effects on the gut microbiome, meaning that it helps healthy gut bacteria proliferate.
Cranberries and Health Conditions
When it comes to health conditions treated with cranberries and cranberry supplements, urinary tract infections are the most common. However, few realize that cranberries may also have benefits for those with diabetes, heart disease, high blood pressure and digestive concerns.
Cranberries and Urinary Tract Infections
In the United States, almost 500,000 people are admitted to the hospital each year due to complications of urinary tract infections, or UTIs as they are commonly called. More common in women than men, UTIs, in addition to being painful, can lead to serious complications, one of the most common being a bacterial infection of the blood. In the United States, almost 11 percent of women reported a urinary tract infection in the previous 12 months. In addition, it is estimated that one in two women will develop at least one urinary tract infection during her lifetime. Worldwide, tens of millions of women get a urinary tract infection each year.
Cranberry supplements appear to be helpful in the prevention of urinary tract infections and are cost-effective, according to a 2014 study in Clinical Infectious Disease. A 2013 study confirmed the effectiveness of cranberry supplements in preventing recurrent urinary tract infections in those at risk. In addition, a 2014 study in the Journal of the American Geriatric Society showed those seniors at high risk who resided in long-term care facilities, such as a nursing home, were 26 percent less likely to have a urine infection if a cranberry supplement was taken.
How do cranberries help? The answer lies in molecules inside the cranberry fruit, which help prevent the e. coli bacteria—the cause of 80 percent—of infections, from sticking to the bladder wall and causing an infection. Suggested dose: As directed on the label.
Cranberries and Diabetes
Diabetes mellitus type 2, or diabetes as it is commonly known, is a lifestyle disease. It is a condition that affects millions worldwide. Those with diabetes suffer from elevated sugar (glucose) levels in the blood, causing oxidative damage to blood vessels, nerves, and organs, such as the kidneys and eyes—an example of oxidation is a car becoming rusty from the effects of weather. Diabetes increases the risk of heart attack, stroke, foot amputation, and kidney failure.
A healthy diet plays a big role in controlling diabetes. A 2017 study concluded that adding cranberries to a high-fat meal could help reduce blood sugar levels in patients with type 2 diabetes while another 2017 study showed cranberries could actually help make insulin more efficient. Additionally, a 2018 study concluded, “Daily cranberry juice (240 mL) consumption for 12 weeks…showed a beneficial effect on glucose control” in those with diabetes. Note, cranberry juice is the natural juice while cranberry cocktail, is loaded with sugar.
Cranberries, Heart and Blood Pressure
Heart disease is a leading killer in the United States, Europe, and Asia. Unfortunately, as more countries adopt the Western lifestyle in place of their ancestral diets, heart disease will continue to progress. In the U.S., alone, deaths due to heart and vascular disease unnecessarily kill almost 1 million people every year. High blood pressure is one of the leading risk factors for heart disease—more than 1 billion of the world’s 7.6 billion people have high blood pressure.
Choosing the right food to consume is one of the most important ways to prevent heart disease and lower inflammation in the arteries and heart. The heart-health benefits of a Mediterranean diet have been proven by multiple studies. A 2013 study in the New England Journal of Medicine, for instance, concluded, “Among persons at high cardiovascular risk, a Mediterranean diet supplemented with extra-virgin olive oil or nuts reduced the incidence of major cardiovascular events.”.
Cranberries may also play an important role. A 2016 study mentions the health benefits of cranberries on heart health, lowering blood pressure and reducing cholesterol. The doctor of the future may recommend adding cranberries to one’ diet as a means of preventing heart disease.
Cranberries and Cancer
One hundred years ago, cancer was rare in the United States, Russia, Japan and China. However, worldwide, cancer is now a leading cause of death. Studies from 2011 and 2012, show cranberries may contribute to anti-cancer benefits. The nutrients in cranberries encourage cancer cells to undergo a process known as apoptosis, in which a cancer cell self-destructs. A 2008 study also notes that lab studies show that cranberries can help prevent growth of breast, colon prostate and lung cancer cells.
In 2016, a study was conducted in which men with prostate cancer were given 1,500 mg of cranberry powder or a placebo. The PSA blood test, a marker for prostate cancer, was reduced by 22 percent in those who consumed the cranberry powder compared to those who took the placebo. A 2015 study showed men who received radiation treatment for prostate cancer had less bladder inflammation when cranberry capsules were taken.
More studies are needed to determine whether or not this will result in clinical significance. There many types of cancer out there and more research is needed to see what role cranberries will play.
Cranberries and Digestive Health
Over 2,000 years ago, Hippocrates stated “All disease begins in the gut”. Science supports this, and focusing on intestinal health is crucial for improving overall health. When we consume foods, we are not only feeding our bodies but also feeding the beneficial bacteria in our gut. These healthy bacteria help keep the body strong and help encourage a healthy immune system. When out intestinal tract is out of balance, illness sets in.
According to studies, the nutrients in cranberries act as a prebiotic, meaning they are a type of “food” for our beneficial gut bacteria, such a bifidobacteria. These bacteria helps prevent overgrowth of potentially harmful pathogenic bacteria in our intestinal tract and helps optimize our digestion and absorption of nutrients.
There are stomach bacteria called Helicobater pylori, which when present, increase the risk for stomach ulcers and stomach cancer. Doctors will frequently test for these bacteria when a patient complains of stomach issues such as acid reflux or gastritis. Studies show that consumption of cranberry juice may help eliminate these bacteria from the stomach. Further, a 2005 study of 189 men demonstrated that 90 days of cranberry juice could suppress the h. pylori infection in their stomachs. If you have been diagnosed with H. pylori by your doctor, discuss whether this herb is an option.
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