Archive 2005 2006 2007 2008

Q: Do mouthwashes with zinc, such as SmartMouth, really work better against bad breath?

A: They might, but more research is needed. Zinc has been studied as an anti-halitosis agent since the 1970s, and a few mouthwashes now contain it.

One brand, SmartMouth, has been heavily advertised. When mixed together (from separate bottles) before rinsing, zinc chloride and sodium chlorite produce zinc ions, which, according to the company, bind to receptors on the surface of mouth bacteria so they can’t form smelly sulfur compounds. Rinsing with SmartMouth affords 12 hours of bad-breath protection, the company claims.

Recent reviews note that various forms of zinc have been shown to reduce oral odor, and that zinc’s effects may be enhanced when combined with other ingredients. Smart-Mouth’s “zinc ion technology” is supposed to make it superior to other zinc mouthwashes. There are plenty of glowing testimonials on websites that sell it—but little hard data to support them.

It’s not known what form of zinc, concentration, and ingredient combinations might offer the best protection against bad breath. Still, if you use a mouthwash and aren’t happy with the results, you might try one with zinc, though it will probably cost more. SmartMouth sells for about $10 for 16 ounces. Advanced Listerine with zinc chloride costs about $5 for a similar size.

Remember: No mouthwash can take the place of thorough brushing, flossing, and regular visits to the dentist. A tongue scraper is another good weapon against bad breath.

Q: What is kefir, and how does it compare to yogurt?

A: Kefir is a cultured dairy product, similar to a yogurt drink, that originated in the Caucasus Mountains straddling Europe and Asia. Its promoters call it “miracle milk” because of its alleged health benefits.

Traditionally, kefir is made by fermenting milk with kefir “grains”—a mixture of bacteria and yeast bound in a gelatinous matrix. The result is tangy like yogurt, but it may also be slightly alcoholic and fizzy, depending on the fermentation time and technique. For safety and consistency, most commercial kefirs use powdered starter cultures instead of the grains. In contrast, yogurt is typically fermented with different strains of bacteria, and not with yeast.

Like yogurt, kefir contains probiotic bacteria. Probiotics can reduce antibiotic-associated diarrhea, and they may help irritable bowel syndrome and other intestinal conditions. Because kefir has more strains of beneficial bacteria than yogurt, it may have a wider range of effects. But despite the claims, there’s no good evidence that kefir—or any probiotic—lowers cholesterol or blood pressure, increases energy, strengthens nails and hair, or prevents cancer and diabetes.

Kefir is rich in protein, calcium, B vitamins, and other nutrients. Choose low-fat or nonfat varieties. Kefir made from soy milk is also available. Traditional kefir is not sweet, but most commercial products have added sugar, along with fruit (or fruit flavors), which adds calories. Commercial brands don’t contain alcohol.

Q: Can laser therapy help me quit smoking?

A: Not likely, but no quit-smoking method has a high long-term success rate. Laser therapy—also called laser acupuncture (though no needles are used) or cold laser—uses low-level laser beams to stimulate various “energy points” on your ears, face, or hands. It’s supposed to promote relaxation and release pain-relieving endorphins to help relieve nicotine withdrawal symptoms.

Many websites tout it—with outlandish claims of up to 90% success rates and “guaranteed results.” But there’s no scientific evidence that it works, and no major health organization endorses it. In a study in the American Journal of Chinese Medicine in 2000, teen smokers were just as likely (or rather, unlikely) to quit smoking after treatment with a real laser as a placebo laser. The FDA approved laser therapy for temporary pain relief, but a loophole allows centers to offer it for smoking cessation if they say they are conducting clinical trials—though it’s unlikely they’re doing rigorous research.

On the other hand, there’s no single best method for quitting smoking. Nicotine gum and patches, certain antidepressants, hypnosis, acupuncture, and support groups may suit different people, so if you’re trying to quit and can’t, it is important to keep trying new things. Laser therapy may help some people, especially if they believe it will. But it’s pricey—about $300 or more—and not covered by insurance.

Q: If one glass of wine is good for you, why not two or three? How about four glasses over the day?

A: For alcohol, as for many other things, moderation is the rule. A little is good, but more is not better. Studies have found that moderate drinkers have the lowest overall mortality rate—lower than nondrinkers or heavy drinkers.

Moderate drinking is defined as one drink a day for a woman, two for a man. A “drink” is 4 to 5 ounces of wine, 12 ounces of beer, or 1.5 ounces of 80-proof liquor, which all contain the same amount of alcohol.

Drinking—especially heavy drinking—increases the risk of some cancers. Thus, the American Cancer Society recommends restricting alcohol or abstaining, even though moderate drinking benefits the heart. Excessive drinking increases the risk of injuries from falls and other accidents. It may also, of course, be a sign of alcoholism.

Q: What are the benefits and risks of douching?

A: Vaginal douching has plenty of risks and no benefits.

About one-third of young American women douche routinely—for example, after menstruation. Many douching products contain fragrances, and manufacturers claim these will help women feel clean and “fresh.” The vagina, however, cleans itself, and douching may kill some of the helpful bacteria that normally reside there. This, in turn, may promote more harmful bacterial and yeast infections.

Douching will not prevent sexually transmitted diseases, as is sometimes claimed. In fact, it can introduce and propel harmful organisms further into the reproductive tract. And it can irritate the vagina and cause chronic discharge and discomfort.

Douching also will not prevent pregnancy. Do not use it as a contraceptive after sexual intercourse. If you’re trying to get pregnant, regular douching may reduce your chances. Douching has been linked to an increased risk of ectopic (outside the uterus) pregnancies, which can be life-threatening, and to pre-term delivery and low birth weights. Some studies have also linked douching with pelvic inflammatory disease.

UC Berkeley Wellness Letter, July 2008