Life Extension Magazine June 2014

Report

The Dangers Of Using Antibiotics To Prevent Urinary Tract Infections

By Alex Johnson

The Dangers Of Using Antibiotics To Prevent Urinary Tract Infections  

Urinary tract infections are one of the most common infections, resulting in more than 11 million visits to the doctor each year1—and most (if not all) of them get treated with antibiotics. But when used for prevention and repetitive treatments, antibiotics pose a public health concern, as their overuse has led to the rise of antibiotic-resistant superbugs.2

That’s why scientists have been working to come up with an alternative to antibiotics. They have discovered that by preventing the bacteria from sticking to the lining of the urinary tract to begin with, it’s possible to treat and prevent urinary tract infections—and as an added bonus, to reduce the overuse of antibiotics.3

Naturally, drug companies are keenly following these developments, intent on commercializing these compounds called FimH inhibitors, which prevent bacteria from sticking to the lining of the urinary tract.4

The problem is, pharmaceutical treatments targeting this mechanism of action are years away from reaching the market. And when they do finally arrive, you can bet they won’t be cheap or necessarily safe.

The good news is that you needn’t wait for FimH inhibitors to become available through your local pharmacy. Cranberry products, long known for their effectiveness in preventing urinary tract infections, already contain naturally specialized molecules that function in exactly the same way as FimH inhibitors.5 Studies show that cranberry juice and extracts inhibit bacterial binding throughout the urinary tract, stopping potential urinary tract infections before they can even begin.

A New Way To Treat And Prevent Urinary Tract Infections

A New Way To Treat And Prevent Urinary Tract Infections 

The vast majority of urinary tract infections are caused by E. coli bacteria.5,6 For these bacteria to create an infection, they have to be able to stick to cells lining the bladder or urethra (the tube through which urine leaves the body).3,5,6 The E. coli strains that are the most successful at causing urinary tract infections have developed a sophisticated set of cell-surface adhesion molecules, which act like tiny grappling hooks to attach themselves to urinary tract tissue.3-5,7

Once attached, the organisms start to reproduce, which causes inflammation, and produces the typical symptoms of a urinary tract infection: burning, painful urination, and a sense of urgency to urinate. If the infection ends up in the kidneys, it can lead to fever, chills, and low back pain.1

Current medical treatment for urinary tract infections mainly involves antibiotics that destroy bacteria (or impede their reproduction).6,8 But the overuse of antibiotics has created a new crisis: antibiotic resistance.6,9 Antibiotics can’t kill every single organism in an infection, and those that survive develop resistance to the drug. As they reproduce, they give rise to new populations that are similarly resistant. It doesn’t take many generations of bacteria until widespread resistance to multiple antibiotics occurs.6,10

In short, the more antibiotics we develop, the “tougher” the germs become. Experts warn that a generation of superbugs is emerging that will be immune to any known antibiotic therapy.

That’s why it’s so important to find a way to prevent urinary tract infections before they begin—and why scientists are working hard to develop synthetic compounds that would make the bacteria incapable of sticking to urinary lining cells.4,7,8,11 Because the most important binding molecule on E. coli cells is called FimH,6,12 the bulk of drug development has focused on creating molecules that fill up the FimH binding sites, eliminating the “stickiness” of the germs.4,6,7 These drugs are referred to as FimH inhibitors.4,13

If the bacteria are unable to bind to the urinary tract lining, they will be eliminated simply by the flow of urine, long before they can set up an infection.6

Laboratory studies show that FimH inhibitors can reduce the amount of bacterial colonization in animal bladders by a factor of almost 10,000 compared with standard antibiotic treatment.6

Fortunately, you don’t have to wait for FimH inhibitors to become available in order to effectively prevent urinary tract infections. The effective characteristics of FimH inhibitors occur naturally in cranberries.14 And that means that you can have access, right now, to a safe, effective way to keep bacteria from sticking to the urinary tract—and ultimately to help prevent urinary tract infections from occurring.

What You Need To Know
Protect Urinary Tract Health With Cranberry

Protect Urinary Tract Health With Cranberry

  • Repeated antibiotic treatment for urinary tract infections is a major contributor to the rise of dangerous antibiotic resistant bacteria.
  • Frequent antibiotic treatment also raises your individual risk for complications such as bacterial overgrowth and difficult-to-treat infections in the future.
  • A new category of drugs, called FimH inhibitors, is under development, aimed at blocking bacteria from attaching to the urinary tract to produce infection.
  • But FimH inhibitors are still far in the future; their effectiveness and safety remain unknown.
  • A simpler, more natural choice is a whole-fruit cranberry supplement; these supplements act in the same way as FimH inhibitors, preventing bacterial adhesion in the urinary tract.
  • Cranberry supplements offer the other benefits of a natural product; they are rich in antioxidant and anti-inflammatory compounds.
  • Cranberry supplements compare favorably with antibiotics in preventing recurrent urinary tract infections, and they are known to cause no increase in resistance.
  • If you are concerned about recurrent urinary tract infections, it’s important for you to begin supplementing with a whole-fruit cranberry concentrate that provides at least 36 mg/day of the important proanthocyanidins that achieve the therapeutic effect.

Cranberries Block Bacterial Stickiness

Cranberries Block Bacterial Stickiness  

For more than 45 years, human studies have demonstrated the effectiveness of cranberry products, especially extracts of the whole fruit, at preventing urinary tract infections. Multiple studies, for example, have shown that when people supplement with cranberry juice or extracts, their urine acquires the ability to block bacteria from attaching to cells lining the bladder, urethra, or vagina.15-20

Cranberry supplements reduce bacterial adhesion regardless of the specific bacterial strain or of bacterial antibiotic resistance.16,21 This gives cranberry products a major edge over standard antibiotic therapy.

Cranberries contain a specific group of polyphenol molecules called proanthocyanidins.21-23 Similar to FimH inhibitors, these molecules may prevent bacteria from sticking to urinary tract lining cells.24,25 While antioxidant proanthocyanidins are found in many plant-based foods, research shows that those from cranberries appear to have more significant anti-adhesion properties.26

Multiple laboratory studies have demonstrated in detail just how effective proanthocyanidins are at reducing bacterial stickiness. One study found that cranberry powder from whole berries decreased the number of bacteria sticking to cells lining the urinary tract from 6.9 to just 1.6 organisms per cell.27

Using atomic force microscopy (an electron microscope that determines forces between individual molecules), scientists were able to measure the rapid reduction in nanoscale adhesive forces between bacteria and lining cells after the addition of cranberry juice to the Petri dish.28 Cranberry treatment produced a 12.4-fold reduction in the force holding bacteria to the cells.

In another study using atomic force microscopy, scientists gave human volunteers a dose of cranberry juice, obtained urine specimens, and then applied them directly to E. coli bacterial cells in culture.29 Urine collected just two hours after cranberry juice consumption cut the bacterial stickiness to levels lower than those obtained with urine collected before the juice dose. The bacterial stickiness continued to drop over the entire eight-hour test.

This study demonstrated that cranberry juice components rapidly enter the urine, and almost immediately lead to a decrease in the stickiness of infection-causing bacteria.29

Purified proanthocayanidin from cranberries has now been shown to be effective at preventing the adherence of multi-drug resistant strains of E. coli to urinary lining cells—showing that these molecules may be effective in preventing urinary tract infections that are difficult to treat with antibiotics.30

In addition to reducing bacterial stickiness, proanthocyanidin molecules offer additional benefits beyond FimH inhibition:

Once proanthocyanidins bind to the bacterial cell surface, they reduce the amount of the sticky projections that the organisms produce.22,31

They change the actual shape and structure of the bacteria, making them less functional.22,31

There’s growing evidence that cranberry extracts reduce the adhesion of other bacterial and yeast species that are often responsible for urinary tract and other infections, giving them a considerably broader spectrum than is likely with FimH inhibitors.32-36

Proanthocyanidins impair E. coli’s swimming ability, limiting their ability to move around even prior to latching on to bladder lining cells,32 which increases the chances of eliminating the organisms from the urinary tract before they can cause an infection.

Cranberries can reduce the bacteria’s ability to form a “biofilm,” the mucous-rich scum that forms on surfaces like urinary catheters.33,34,36 This may reduce the risk of serious urinary tract infections caused by necessary medical hardware.

Unlike FimH inhibitors, cranberry extracts also contain antioxidants and anti-inflammatory molecules.15,33,37 Together, these components can reduce damage to human cells and the symptoms that result from the inflammatory reaction to the organism.37

Cranberry treatment, especially in capsules, does not have known significant drug interactions or side effects, something that’s still unknown about FimH inhibitors.21,38

Understanding Urinary Tract Infections
Understanding Urinary Tract Infections

A urinary tract infection is any infection of the components of the urinary system that make, store, and excrete urine.

Women have a lifetime chance of between 40 and 50% of having at least one urinary tract infection; their risk is 50 times that of men for such infections.25,45 Recurrent urinary tract infections are also common in women, with up to one-third developing at least one recurrence.25 When recurrences happen more frequently than twice in six months, or three times in one year, preventive antibiotics are usually begun.21

Not all urinary tract infections are the same. The simplest kind is an infection limited to the urinary bladder. This “bladder infection,” or cystitis, produces pain during urination, along with a need to urinate frequently and urgently. Some patients experience low abdominal pain as well.

A kidney infection (pyelonephritis) is a much more serious infection, involving the urine-producing tissue of the kidney. Kidney infections typically cause all the symptoms of a bladder infection, along with fever, chills, malaise, and low back pain. These infections usually arise from a simple bladder infection, and they pose the risk of sepsis, or “blood poisoning.”

Men may also develop bacterial infections of the prostate, called acute or chronic bacterial prostatitis.

Regardless of the type or location of a urinary tract infection, the vast majority are caused by virulent strains of E. coli bacteria, most of which originate in fecal matter. Simply contaminating the urinary tract with these organisms is not enough to start an infection, however.

The germs must first attach themselves firmly to the urinary tract lining. Blocking that attachment is therefore a major target of drug developers, although cranberry supplements produce an identical kind of adhesion blocking with fewer side effects and no risk of antibiotic resistance.

Life Extension Magazine June 2014

Report

The Dangers Of Using Antibiotics To Prevent Urinary Tract Infections

By Alex Johnson

Clinical Studies Validate Cranberry Effectiveness

Clinical Studies Validate Cranberry Effectiveness 

Cranberries have been used for generations to help boost urinary tract health. It’s only in the past dozen or so years, however, that scientists have come to a better understanding of how cranberry products work to combat bacterial adhesion, reduce oxidant stress, and fight inflammation. The most compelling studies are those that directly examine how cranberry products reduce the frequency or severity of urinary tract infections.

An early pilot study evaluated women between 25 and 70 years old who took 200 mg of a concentrated cranberry extract twice a day.39 All of these women had a history of at least six urinary tract infections in the past year. During the 12-week course of the study, not a single woman had a urinary tract infection.39 Even better, two years later, all of those who continued to take the cranberry supplement remained free of urinary tract infections. That’s 100% protection for a group of people who previously had averaged one urinary tract infection every two months.

A large meta-analysis study of 10 individual clinical trials involving 1,049 patients showed that cranberry products significantly reduced the incidence of urinary tract infections at 12 months, lowering the risk of an infection by 35% compared with control groups.40

Still more recently, several studies have compared the effect of cranberry extracts with the most commonly used antibiotics in preventing recurrent urinary tract infections. These studies have demonstrated good efficacy of the cranberry treatment in comparison to standard antibiotics.41,42

One study showed that cranberry extract had similar effectiveness to the antibiotic trimethoprim at preventing urinary tract infections.41

uropathogenic E.coli

Another study found that the antibiotic combination of trimethoprim and sulfamethoxazole was only slightly more effective at preventing urinary tract infections than cranberry capsules. (Patients took 500 mg twice daily of cranberry capsules, or once-daily doses of the antibiotic combination.42) However, patients treated with antibiotics had a 62% greater amount of antibiotic-resistant organisms during the study, compared to those receiving cranberry. This study has been widely cited as an example of the reasonable trade-offs between cranberry and antibiotic treatment; over the long term, it seems likely that the cranberry recipients will develop fewer infections with dangerous multiple antibiotic-resistant strains of organisms.

As with any therapy directed against microorganisms, the question arises whether cranberry supplements might in some way alter the normal bacterial population of the intestinal or vaginal tracts. Certainly antibiotics do this, as we’ve seen, and with often devastating effects.

Research shows that not only do cranberry products not unfavorably affect normal bacteria, but in fact they also help eliminate certain disease-causing germs living in the genito-urinary tract in up to 42% of patients.18 Similarly, studies show that cranberry supplementation does not have any negative interactions with existing antibiotics.43

What To Look For In A Cranberry Supplement
What To Look For In A Cranberry Supplement

Cranberry products, especially those in capsule form and made from whole fruit, provide undoubted protection against recurrent urinary tract infections, especially in older women who are at the greatest risk of infection. The strong research proving cranberry’s benefits for treating and preventing urinary tract infections led the European Urological Association to recommend the use of cranberry preparations containing not less than 36 mg of proanthocyanidins per day as a preventive strategy against urinary tract infections.38

It’s important to do your research before choosing a cranberry supplement. A 2012 study surveying cranberry supplements found that only four of 19 products studied actually provided 36 mg of total proanthocyanidins per day; some provided none at all.46

In order to take advantage of cranberry’s benefits, make sure you’re taking a cranberry supplement that’s derived from whole fruit, and that will deliver the recommended 36 mg/day of the proanthocyanidins that prevent bacteria from sticking.

Summary

Urinary tract infections afflict millions of Americans, overwhelmingly women.1 Nearly 20% of women who have had one urinary tract infection will have another and this risk increases with each infection so that a woman who has had three urinary tract infections in her lifetime has an 80% chance of developing a fourth.44 Those women (and the few men with similar problems) are often placed on antibiotic preventive therapy to reduce the chance of another recurrence.

But antibiotic treatment poses major risks to the individual and to the health of the public. Repeated treatment produces drug-resistant organisms, which are much more difficult to treat as time goes by.

A new family of drugs is under development that will block the first step in urinary tract infections, binding of the bacteria to the bladder lining. But those drugs are still far in the future, and their safety and effectiveness profiles are as yet unknown.

Whole-fruit cranberry supplements, on the other hand, are already recognized to block bacterial binding to the urinary tract linings, and their safety profile is well-established. Concentrated supplements avoid the excess sugar load and occasional stomach upset that can be caused by cranberry juice.

Supplements with at least 36 mg of cranberry proanthocyanidins are recognized by international agencies as being appropriate for use in prevention of urinary tract infections.38 Capsule preparations of these supplements minimize the risk of stomach upset.

If you have or are concerned about recurrent urinary tract infections, you owe it to yourself to start supplementing with a whole-fruit cranberry product today. You’ll be benefiting yourself and your entire community by doing so, as you lower your risk for contributing to the epidemic of antibiotic resistance.

If you have any questions on the scientific content of this article, please call a Life Extension® Health Advisor at 1-866-864-3027.

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