Researchers in Japan are reporting new evidence that the ordinary vinegar — a staple in oil-and-vinegar salad dressings, pickles, and other foods — may live up to its age-old reputation in folk medicine as a health promoter. They are reporting new evidence that vinegar can help prevent accumulation of body fat and weight gain.

Tomoo Kondo and colleagues note in the new study that vinegar has also been used as a folk medicine since ancient times. People have used it for a range of ills. Modern scientific research suggests that acetic acid, the main component of vinegar, may help control blood pressure, blood sugar levels, and fat accumulation.

Their new study showed that laboratory mice fed a high-fat diet and given acetic acid developed significantly less body fat (up to 10 percent less) than other mice.

Importantly, the new research adds evidence to the belief that acetic acid fights fat by turning on genes for fatty acid oxidation enzymes. The genes churn out proteins involved in breaking down fats, thus suppressing body fat accumulation in the body.