Vinegar has been around for thousands of years, and is credited with many health and hygiene properties.
An important health effect of vinegar is its ability in aiding blood glucose control. It was reported first by Japanese researchers in 1988. Several other studies have pointed out the same findings; that is, vinegar reduces the speed at which sugars get absorbed into the bloodstream.
One study by Italian researchers published in 1995 shows that when healthy subjects consumed about 4 teaspoons (20 ml) of vinegar as a salad dressing with a meal that included white bread with a little less than two ounces (50 grams) of carbohydrates, there was a 30 percent reduction in their glycemic response, or rise in blood sugar. That is compared to the same meal without vinegar.
Separate placebo-controlled trials have corroborated the meal time, antiglycemic effects of 20g vinegar in healthy adults. Sugiyama and colleagues documented that the addition of vinegar or pickled foods to rice (e.g., sushi) decreased the GI (Glycemic Index) of rice by 20 to 35 percent.
From these studies, we can safely deduce that making salad dressings involving the use of vinegar is a healthy habit to support a healthy lifestyle.