Health: Body News.

Mouthwash Merits

Mouthwash that contains certain essential oils can reduce plaque and gum inflammation, a new study has shown. After six months, 76 people who brushed, flossed, and rinsed with Listerine twice a day had a 21 percent lower gingivitis score and a 52 percent lower plaque score than 76 people who did the same regimen with a control mouthwash. (The study was sponsored by Pfizer, Listerine's manufacturer.) The researchers speculate that the plant-derived oils in Listerine, which include thymol and eucalyptol, help penetrate plaque. Previous studies found that Listerine was at least as good as flossing for reducing gum inflammation, a precursor to gum disease. But the research hasn't assessed mouthwash's ability to prevent gum disease or dental decay, points out Matthew Messina, a dentist in Cleveland and an advisor to the American Dental Association. Although Listerine and the prescription rinse Peridex kill bacteria, he says, they won't remove food particles like toothbrushes and floss do, so the best advice is to use all three.

25%

of Americans surveyed in 2003 reported that they brush their teeth after every meal, up from 11.5 percent in 1997. -- American Dental Association

Yo-Yo No-No

Losing and regaining weight repeatedly can weaken the immune system. Cornelia Ulrich, a scientist at Fred Hutchinson's Cancer Research Center in Seattle, and her colleagues surveyed 114 overweight and sedentary but otherwise healthy women. Those who reported losing weight more than five times in the previous 20 years had about a third lower immune-system ...