Research suggests that a little bit of vinegar could have a beneficial effect on blood sugar levels.

In a study, ingesting a couple tablespoons of apple cider vinegar before a high-carbohydrate meal was found to help dampen expected spikes in blood sugar levels from the meal. For a bit of vinegar's benefit, try starting off your next pasta meal with a salad splashed with red wine vinegar and olive oil.

Vinegar is no substitute for healthy eating habits or for proven methods of blood sugar control. The beneficial effects of vinegar on blood sugar levels may not apply to healthy individuals, and more research is needed to confirm its potential benefits for other populations. In a recent study, ingesting 20 grams (approximately 2 tablespoons) of apple cider vinegar before eating a high-carbohydrate meal improved insulin resistance. Study participants who experienced the blood sugar control benefits from vinegar were either diabetic or had insulin resistance syndrome. They followed the 20 grams of apple cider vinegar with a high-carbohydrate meal consisting of a white bagel, butter, and orange juice. After the high-carbohydrate meal, the acetic acid from the earlier serving of vinegar appeared to reduce blood sugar levels by 19 percent in people with diabetes and by 34 percent in people with insulin resistance. Acetic acid may help lower blood sugar levels by suppressing enzymes required to break down sugars, resulting in slower absorption. The best way to keep blood sugar levels steady is to eat a balanced diet, eat at regular intervals, and engage in a moderately strenuous program of physical activity. If you have diabetes or insulin resistance syndrome, follow your healthcare provider's advice.

Vinegar improves insulin sensitivity to a high-carbohydrate meal in subjects with insulin resistance or type 2 diabetes. Johnston, C. S., Kim, C. M., Buller, A. J., Diabetes Care 2004 Jan;27(1):281-282.